942 resultados para cultivated tomato


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作为复杂的生态过程之一,土壤侵蚀常常被空间景观异质性影响。深入地研究土壤侵蚀与植被景观的相关性对以减少水土流失为目的的河流中上游生态恢复工作来说十分重要。本文利用遥感和GIS 技术,对岷江源头区的植被景观和土壤侵蚀动态(1974年~2002 年)进行分析,并从景观生态学的角度,系统地研究了整体植被景观和不同的植被景观类型的景观特征与土壤侵蚀量、侵蚀模数以及土壤侵蚀强度的相关性,得出的结论主要有以下几个方面:1. 从植被景观特征与土壤侵蚀量和土壤侵蚀模数的相关性的角度出发,森林能最大限度地控制土壤侵蚀,草地对土壤侵蚀的控制能力不及森林,而且能在一定程度上增加土壤侵蚀。灌丛与土壤侵蚀量和土壤侵蚀模数的关系则比较复杂,还需要进一步地研究。农用地与森林、灌丛、草地等植被类型不同,它的增加将会明显地增加产沙量。随着各景观类型(灌丛除外)分布的镶嵌性的增强,土壤侵蚀量和侵蚀模数会减少。2. 从植被景观特征与土壤侵蚀强度的相关性的角度出发,在景观水平上,植被景观的景观多样性指数、景观破碎度指数、景观形状指数和景观聚集度指数均与土壤侵蚀强度有明显的相关性。在较轻侵蚀强度的区域中的植被景观具有更丰富的多样性和更低的破碎程度,景观的组分和结构都更加复杂,景观斑块的形状也比较复杂。同时,植被景观的空间异质性也较强。3. 从不同景观类型对土壤侵蚀强度的控制能力大小看:针叶林> 落叶阔叶林>针阔混交林> 灌丛> 草地> 农用地。同时,对于除农用地以外的其他植被景观类型来说,增加其平均斑块面积和形状的复杂性会在一定程度上减少土壤侵蚀强度。而对于农用地来说,斑块形状的简单化以及分布形式的均匀镶嵌化则是减少土壤侵蚀强度的有效手段。 As a complex ecological process, soil erosion is affected by the spatial landscape heterogeneity.The relation between soil erosion and landscape characteristic weights a lot in ecosystemrestoration that aim to control the soil erosion in watershed. By means of RS and GIStechniques, this study analyzed dynamic variations in landscape characteristic and soil erosionin the Minjiang headwater region over a period of 28 years to elucidate the interrelationshipsbetween landscape characteristics and soil erosion. The results are as follows:1. In terms of relation between landscape characteristics and soil erosion module, forest canmitigate the soil erosion much better than grass. The relation between shrub and soil erosionmodule is rather complicated that requests further more study to confirm how those two factorscorrelated with each other. Cultivated land differs from other landscape classes in creatingconditions most favorable for soil erosion. Moreover, the dispersion of all landscape classes,except for shrub, correlates with soil module negatively.II2. In terms of relation between landscape characteristics and soil erosion strength, the diversityindex, fragment index, shape index and contagion index of the vegetation in Minjiangheadwater region at landscape-level correlated with soil erosion clearly. Vegetation landscapein No and Slight erosion region is more diverse, fragmental and constructed in more complexway. The shape of those vegetation patches is also more complicated. The spatial heterogeneityof the vegetation landscape is much more evident than that located in moderate and strong erosion region too.3. At class-level, different landscape classes affected soil erosion strength in different ways.Taking the mitigating effect on erosion strength into consideration, landscape classes can bearranged in this turn: coniferous forest > Deciduous forest > Mixed forest > Shrub > Grassland > Cultivated land. At the same time, for most landscape classes, except for cultivated land,increase the mean patch size and complicate the shape of patch will help to relieve the erosionstrength. However, for cultivated land, simplifying the shape of patch and scattering thepatches have the same effect.

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近年来,随着对作物重茬(连年种植)障碍原因的深入研究,植物的化感作用越来越受到国内外众多学者的重视。而作为重要调料和药用植物的生姜,其连作障碍也备受关注,系统地研究生姜化感作用将有助于理解和最终解决生姜连作障碍问题。本文通过研究生姜不同部位、不同浓度的水浸液对与其间作的两个物种(大豆和四季葱)种子的萌发及幼苗生长的影响,从而证明生姜化感作用的存在;并通过温室盆栽实验研究了生姜的自毒作用(即研究生姜不同部位、不同浓度的水浸液对其幼苗的形态、生理生化、光合作用、土壤酶、土壤微生物多样性及土壤养分的影响),从而揭示生姜退化和衰老的机制,并为生姜筛选出合适的间作物种提供科学依据,对生姜连作障碍提出科学的解决方法。主要研究结果如下: 1. 与对照相比,生姜所有部位(根茎、茎、叶)、所有浓度(10、20、40、 80 g l-1)的水浸液均抑制了大豆种子和葱籽的萌发率、幼苗生长、水分吸收和脂肪酶活性,并且其抑制程度随着水浸液浓度的增加而增强,其生姜各部位水浸液抑制效应的强弱顺序为茎>叶>根茎。这一结果表明生姜根茎、茎、叶含有能够抑制大豆种子和葱籽种子萌发和幼苗生长的水溶性化感物质。根茎是生姜的主要收获部位,而生姜的残株(主要是茎和叶)应该从大田中处理掉以减轻其抑制效应。生姜水浸液中主要化感成分包括:根茎水浸液中主要是丁香酸和伞花内脂;茎水浸液中主要是阿魏酸,且其含量最高为73.4 ug/g;叶水浸液中除了阿魏酸,其他六种物质均检测出来,但含量较高的主要有丁香酸、伞花内脂和香豆酸。 2. 生姜茎和叶不同浓度的水浸液均显著抑制了生姜幼苗的株高、每株叶片数和叶面积,其抑制程度随着水浸液浓度的增加而有所增强,而生姜幼苗每株分枝数差异不显著;同时生姜水浸液也极大程度地影响了生姜幼苗的生物量(包括地下生物量、地上生物量和总生物量,均为鲜重)。在同一浓度下,茎水浸液对生姜幼苗形态指标及生物量指标均显示出最强的抑制作用,叶水浸液次之,根茎水浸液最弱。与对照相比,低浓度的生姜根茎水浸液提高了生姜幼苗叶片内四种抗氧化酶(SOD、POD、CAT、APX)活性,高浓度的根茎水浸液抑制了四种抗氧化酶活性,而茎和叶水浸液均随着浓度的增加而抑制了四种抗氧化酶活性,三种水浸液均随着浓度的增加降低了生姜幼苗叶片内叶绿素的含量,而增加了生姜幼苗叶片的相对电导率和丙二醛含量。同时,三种水浸液均随着浓度的增加降低了生姜幼苗的光合参数(包括胞间CO2浓度、气孔导度、蒸腾速率及净光合速率)。 3. 三种生姜水浸液对所测六种土壤酶活性均产生了不同程度的影响,其中影响最大的是酸性磷酸酶和蔗糖酶,在10 g l-1 时就达到了显著水平,并且所有酶均有随着水浸液浓度增加而增大的趋势;相同部位的水浸液随着浓度的增加,细菌和真菌的数量呈增加趋势,而放线菌的数量呈减少趋势;三种生姜水浸液均随着浓度的增加降低了土壤中有机质的含量,加剧了土壤中硝态氮含量的积累,根茎水浸液对土壤有效磷、速效钾和铵态氮均显示出低浓度提高其含量而高浓度降低其含量的趋势,而茎和叶水浸液则随着浓度的增加均降低了其含量。 4. 与生姜单作相比,所有间作系统均在旺盛生长期和收获期不同程度地提高了土壤酶活性,同时也增加了土壤细菌数量及土壤微生物总数但不显著;所有间作系统在旺盛生长期和收获期均不同程度地影响了土壤真菌及放线菌数量(增加或减少),所有间作系统间的多样性指数差异不显著,除了旺盛生长期四种作物(生姜-大豆-四季葱-大蒜)的间作模式显著降低了多样性指数,其值仅为生姜单作的33.18%;生姜与大豆间作不仅提高了19.6%的生姜产量而且获得了较好的经济效益,并且,所有间作系统均显著抑制了生姜姜瘟病的发生。 5. 不同栽培模式不同程度地影响了收获期生姜的株高、分枝数、根茎产量及内在品质。其中处理2显著地促进了生姜的分枝(10.5%),同时处理2、3和4也促进了生姜的生长(株高分别增加了15.0%、11.4%和14.0%),并且这三个处理提高了生姜的产量;处理2和3能有效提高生姜块茎中维生素C(分别较单作生姜显著提高了3.29%和4.05%)、处理3显著提高了可溶性糖(8.2%)、姜辣素(4.6%)和蛋白质等有益物质的含量,降低硝酸盐有害物质的含量(处理2显著降低了14.0%),改善了姜块的外观和内在品质。并且,生姜与大豆间作具有最高的纯收入和产投比,分别较生姜单作提高了24.80%和8.8%。Recently, allelopathy has been more and more paid attentions by national and foreign scholars with profound research on reasons of crop replanted (continuous planted) obstacle. Ginger rhizome is valuable all over the world either as a spice or herbal medicine and ginger replanted obstacle is also paid attentions. Systematic research on ginger allelopathy will contribute to understanding and ultimate solving problem of ginger replanted obstacle. The effects of ginger aqueous extracts with different parts and concentrations on seed germination and early seedling growth of soybean and chive were studied in this article to testify that ginger existed allelopathy. Furthermore, ginger autotoxicity was also studied by pot experiment in greenhouse (namely research on effects of ginger aqueous extracts with different parts and concentrations on morphological indexes, physiological and biochemical indexes, photosynthesis, soil enzymes, soil microbial diversity and soil nutrients) to reveal mechanism of ginger degeneration and senescence, provide scientific basis for selecting appropriate intercropping species and put forward scientific resolvent for ginger replanted obstacle. The main results were as follows: 1. All aqueous extracts at all concentrations inhibited seed germination, seedling growth, water uptake and lipase activity of soybean and chive compared with the control, and the degree of inhibition increased with the incremental extracts concentration. The degree of toxicity of different ginger plant parts can be classified in order of decreasing inhibition as stem>leaf>rhizome. The results of this study suggested that rhizome, stem and leaf of ginger contained water soluble allelochemicals which could inhibit seed germination and seedling growth of soybean and chive. The rhizome is the main harvested part of ginger. The residue (mainly stems and leaves) of the ginger plant should be removed from the field so as to diminish its inhibitory effect. The main allelopathic components of three kind of aqueous extracts were as follows: Rhizome extract chiefly contained syringic acid and vmbelliferone and stem extract mainly contained frulic acid whose content was the highest (73.4 ug/g). The other six substances were detected except of frulic acid, but only contents of syringic acid, vmbelliferone and p-coumaric acid were higher. 2. Stem and leaf aqueous extracts of ginger with different concentrations significantly inhibited plant height, leaf numbers per plant and leaf area, and the degree of inhibition increased with the incremental extracts concentration. However, tiller number per plant of ginger seedling showed no significant difference. At the same time, ginger aqueous extracts also influenced biomass including under-ground biomass, above-ground biomass and total biomass (fresh weight) to a large extent. Under the same concentration, stem aqueous extract showed the mostly inhibitory effect on morphological indexes and biomass indexes of ginger seedling. Rhizome aqueous extract showed the leastly inhibitory effect and leaf aqueous extract was intervenient. Enhanced concentration of ginger aqueous extracts significantly reduced total chlorophyll content, accompanying with increases in memberane permeability (REL) and lipid peroxidation (MDA). Compared with the control, rhizome ginger aqueous extract of lower concentration (10 g l-1) increased the activities of major antioxidant enzymes (superoxide dismutase, SOD; peroxidase, POD; catalase, CAT; ascorbate peroxidase, APX) of ginger leaf tissue and higher concentration inhibited the activities of four antioxidant enzymes. However, stem and leaf aqueous extract inhibited the activities of four antioxidant enzymes with increase in concentration. Meanwhile, enhanced concentration of ginger aqueous extracts significantly reduced photo-parameters of ginger seedling (including CO2 concentration, stoma conductivity, net photosynthesis rate and transpiration rate). 3. Rhizome, stem and leaf ginger aqueous extract showed different effect on six soil enzyme activities, and acid phosphatase and invertase showed significant effect when aqueous extract concentration got 10 g l-1. Furthermore, six soil enzyme activities increased with increase in aqueous extract concentration. Bcterial and fungi number tended to increase while antinomyces tented to decrease with the increase in aqueous extract concentration of identical part. Ginger aqueous extracts reduced soil organic matter content with increased concentration, accompanying with NO3-—N accumulation in soil. Rhizome aqueous extract showed the same tendency for available P, available K and NH4+—N, namely lower concentration increased their contents in soil and higher concentration reduced their contents. While stem and leaf aqueous extracts reduced their contents with the increamental concentration. 4. All intercropping systems increased soil enzyme activities to different extent both at VGS and at HS compared to solo ginger. All intercropping systems increased the colony numbers of soil bacteria and total of soil microbe but not significantly either at VGS or at HS. All intercropping systems increased the colony numbers of soil fungi and actinomytes to a different extent (increase or decrease) both at VGS and at HS. For DI, difference between all cultivation patterns and S-G was not significant either at VGS or at HS except that G-S-C-G whose value was only 33.18% of S-G at VGS significantly decreased. G-S not only increased ginger yield by 19.6% but also obtained better economic benefit. Furthermore, all intercropping systems significantly inhibited occurrence of bacterial wilt of ginger. 5. Different cultivated pattern influenced plant height, tiller numbers, rhizome yields and intrinsic quality of ginger. Treatment 2 significantly facilitated tiller occurring (10.5%). Treatment 2, 3 and 4 promoted ginger growth (plant height respectively increased 15.0%、11.4% and 14.0%) and enhanced rhizome yields. Treatment 2 and 3 effectively increased vitamin C content (significantly increased 3.29% and 4.05% compared to solo ginger). Treatment 3 significantly increased contents of beneficial substances such as soluble sugar (8.2%), gingerols (4.6%) and protein. Treatment 2 significantly decreased contents of deleterious substance namely nitrate (14.0%) and improved appearance and intrinsic quality of ginger rhizome. Furthermore, treatment 2 (ginger/soybean intercropping) could obtain better economic benefit and showed the highest net income and ratio of benefit and cost whose values respectively increased by 24.80% and 8.8% compared to solo ginger.

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同源四倍体水稻(2N=4X=48,AAAA)是由二倍体水稻(2N=2X=24,AA)通过秋水仙素诱导染色体加倍后得到的新品系,具有优良的抗病性以及较高的蛋白质含量。因此,在四倍体水平上挖掘水稻的增产潜力成为水稻育种的新手段。同源四倍体水稻具有很强的遗传可塑性和很弱的遗传保守性,利用其作为水稻远缘杂交的桥梁,从野生物种中不断地引进有益的基因,这将有助于杂交水稻的多代利用和固定水稻的杂种优势。但是迄今为止,还没有关于同源四倍体水稻遗传多样性,遗传背景的报道。目前世界关于同源四倍体水稻的研究主要集中在中国,主要研究方向为培育、筛选结实正常的亲本材料,配置和筛选结实率正常或接近正常的组合。经过几十年研究,虽然在材料构建,细胞学研究等方面取得了较大进展,但同样由于结实率低的瓶颈问题未解决,而使多倍体水稻育种未能取得实质性进展。而近年来一些关于同源四倍体水稻低结实率机理的细胞学研究也由于缺乏统计学数据而缺乏说明性。本文用SSR标记,对选取的36个结实率正常同源四倍体水稻三系亲本和14个来源二倍体亲本,分析他们的遗传差异和群体遗传结构。本文还利用我们培育的高、低结实率的同源四倍体水稻恢复系、优良保持系和杂种F1及二倍体对照为材料,进行系统深入的细胞遗传学研究,进一步探讨同源四倍体水稻有性传递后代的发育过程,探索分裂期染色体行为特征与遗传性状稳定性的关系,为进一步选育多倍体水稻品种并将其应用于生产提供理论依据。同源四倍体水稻突变株D4063-1直链淀粉含量比来源二倍体明恢63下降一半,即其直链淀粉含量为5.23%,为研究其直链淀粉含量下降的原因,本文还根据普通水稻Wx基因设计引物,扩增测序获得了D4063-1Wx基因的全序列,与已报道Wx基因进行比对分析,并根据D4063-1和籼稻、粳稻的序列差异并根据D4063-1在该片段上的特征序列位点设计了用于识别D4063-1的寡核苷酸片段,为快速、准确的鉴别低直链淀粉的D4063-1创造了条件。 SSR标记具有基因组分布广泛、数量丰富、多态性高、容易检测、共显性、结果稳定可靠、实验重现性好、操作简单、经济、易于高通量分析等许多优点,被认为是用于遗传多样性、品种鉴定、物种的系统发育、亲缘关系及起源等研究的非常有效的分子标记。本研究选取了中国科学院成都生物所培育的同源四倍体和二倍体水稻亲本,并用36个微卫星标记进行了遗传差异和种群遗传结构分析。在50个品系中,我们观察到较高水平的多态性,每基因等位基因数(Ae)分布于2至6之间(平均值3.028),多态性信息含量(PIC)分布于0.04至0.76之间(平均值0.366);期望杂合度(He)分布于0.04至0.76之间(平均值0.370),Shannon指数(I)分布于0.098至1.613之间(平均值0.649)。同源四倍体品系的等位基因数,期望杂合性和Shannon指数都比二倍体品系高。在供试50个品系中,较多材料均发现Rare基因,根据SSR多态性指数我们构建了同源四倍体和二倍体水稻的核心指纹库。F-统计值表明遗传差异主要存在于同源四倍体品系中(Fst=0.066)。聚类分析结果表明50个品系可以分为4个组。I组包括所有的同源四倍体和二倍体籼稻保持系,以及一个同源四倍体籼稻雄性不育系及其来源二倍体。II组仅包括IR来源的品系。III组比II组和IV组更复杂,包括同源四倍体和二倍体籼稻恢复系品系。IV组包括同源四倍体和二倍体粳稻品系。此外,由于等位基因及配子的遗传差异,同源四倍体与二倍体品系中存在单位点和双位点的遗传差异。分析结果表明,二倍体和四倍体水稻基因库的不同,其中遗传变异可以区分四倍体与二倍体水稻。同源四倍体水稻具有长期而独立的遗传性,我们能够选育并得到与二倍体亲本相比有特殊优良农艺性状的品系。 本研究以高结实率的同源四倍体水稻恢复系DTP-4、D明恢63及优良保持系D46B为材料进行农艺性状及细胞遗传学比较研究。DTP-4、D明恢63及保持系D46B的的染色体组成均为2N=4X=48,花粉母细胞具有较为理想的减数分裂行为,配对染色体的比率在99%以上,这与理论染色体组构成相符。DTP-4和D明恢63PMC减数分裂各个时期单价体和三价体的比例都非常低,而在MI, PMC观察到较多的二价体和四价体且四价体多以环状形式出现,其最大频率的染色体构型分别为12II 6IV和10II 7IV。恢复系DTP-4和D明恢63在MI四价体频率分别为2.00/PMC和2.26/PMC,而保持系D46B在MI四价体频率为6.00/PMC,极显著地高于恢复系品系,表明保持系D46B具有更好的染色体配对性质;AI保持系D46B的染色体滞后频率为10.62%,远低于恢复系材料DTP-4和D明恢63的19.44%和23.14%,接近二倍体对照明恢63的7.30%水平;TI保持系D46B具有比恢复系更低频率的微核数。而在TII,D46B的正常四分小孢子比率不但高于恢复系品系甚至高于二倍体对照。对高低结实率的同源四倍体水稻恢复系和杂种F1代的花粉育性,结实率和细胞遗传学行为进行了比较研究。DTP-4, D明恢63, D46A´DTP-4和D46A´D明恢63的花粉育性和结实率比D什香和D46A´D什香显著提高。减数分裂分析的结果表明,DTP-4,D明恢63,D什香,D46A´DTP-4,D46A´D明恢63和D46A´D什香其减数分裂染色体构型分别为:0.05I +19.96 II (9.89棒状+10.07环状) +0.01III + 2.20 IV, 0.11I +19.17 II (8.90 棒状+10.37 环状) +0.09III + 2.26 IV + 0.01 VI, 1.33I +9.46 II (4.50 棒状+4.96 环状) +0.44III + 6.02 IV + 0.09VI + 0.09 VIII, 0.02I +14.36 II (6.44 棒状+7.91 环状) +0.01III + 4.80IV + 0.01VIII, 0.06 I +17.67 II (11.01 棒状+6.67 环状) +0.06 III + 3.10 IV + 0.01 VI and 1.11 I +11.31 II (5.80 棒状+5.51 环状) +0.41 III + 5.63 IV+0.03VI+0.03VIII。在同源四倍体水稻恢复系和杂种F1代材料中,最常见的染色体构型为16II +4IV和12II +6IV。在减数分裂过程中,结实率较高的材料染色体异常现象较少而结实率较低的材料染色体异常现象较严重。在杂种F1代中,二价体的比例要低于其相应的恢复系亲本,同样的,单价体,三价体和多价体的比例相比其恢复系亲本也偏低。然而,在减数分裂MI,杂种F1代中四价体的比例要显著高于其恢复系亲本。在中期I,每细胞单价体的比例和花粉育性呈现出极高的负相关(-0.996),当单价体数目升高时,花粉育性下降。其次是每细胞三价体的比例(-0.987),之后则是每细胞多价体的比例与花粉育性的负相关(-0.948)。但是统计分析表明,二价体和四价体的比例对花粉育性和结实率没有显著影响。这一结果表明出了花粉育性和细胞减数分裂行为的相关性,同源四倍体的减数分裂行为为筛选高结实率的同源四倍体种系提供了理论依据。 突变体是遗传学研究的基本材料。利用突变体克隆水稻基因,并进而研究基因的生物学功能是水稻功能基因组学的重要研究内容。本课题组在多年的四倍体水稻育种研究中已获得多个低直链淀粉含量突变体,其中一些突变体在直链淀粉含量下降的同时,胚乳外观也发生了显著改变,呈半透明或不透明。同源四倍体水稻突变株D4063-1直链淀粉含量比来源二倍体明恢63下降一半,即其直链淀粉含量为5.23%。为研究其直链淀粉含量下降的原因,我们根据普通水稻Wx基因设计引物,扩增测序获得了D4063-1Wx基因的全序列,与已报道Wx基因进行比对分析;同源四倍体水稻D4063-1Wx基因最显著变化为在外显子序列中发生了碱基缺失,导致移码突变,在第9外显子终止密码子提前出现。D4063-1Wx基因碱基位点的变化还导致了其序列上的酶切位点的变化,对常用限制性内切酶位点分析分析结果表明同源四倍体水稻相对于籼稻和粳稻多了2个sph1酶切位点,相对于粳稻减少了6个Acc1,增加了4个Xba1,1个Xho1,1个Pst1和1个Sal1酶切位点。聚类分析表明D4063-1Wx基因序列与籼稻亲源关系较近,由此推测D4063-1Wx基因来源于籼稻的Wxa基因型。另外,根据D4063-1Wx基因的碱基差异,我们推测D4063-1Wx基因外显子碱基变化导致的RNA加工障碍是其直链淀粉降低的主要原因,并可能与其米饭较软等品质相关。本文还根据D4063-1和籼稻、粳稻的序列差异并根据D4063-1在该片段上的特征序列位点设计了用于识别D4063-1的寡核苷酸片段,并作为PCR反应的引物命名为AUT4063-1,将该引物与我们设计的扩增普通籼稻、粳稻的Wx基因引物F5配合使用建立了识别D4063-1的显性和共显性两种检测方式的分子标记,为快速、准确的鉴别低直链淀粉的D4063-1创造了条件。 研究同源四倍体水稻基因组的遗传差异,探索同源四倍体水稻的遗传规律,研究分裂期染色体行为特征与遗传性状稳定性的关系,旨在揭示四倍体水稻中同源染色体配对能力的遗传差异,为进一步选育多倍体水稻品种并将其应用于生产提供理论依据。 Autotetraploid rice (2N=4X=48, AAAA) is a new germplasm developed from diploid rice (2N=2X=24, AA) through chromosomes doubling with colchicines and is an excellent resource for desirable resistance genes to the pathogens and high protein content. Therefore, heterosis utilization on polyploidy is becoming a new strategy in rice breeding. At present, the main research on autotetraploid rice centralizes in China. Breeding effort has been made to improve autotetraploid rice genetically, however, the progresses are limited due to higher degree of divergence between hybrid sterility and polygenic nature. But to date, almost nothing is reported about the genetic diversity, original and genetic background of autotetraploid rice. Despite several reports on cytological analysis of the mechanisms of low seed set in autotetraploid rice still the results are inconclusive due to lack the statistical evaluation. Therefore, the study on the mechanisms of low seed set in autotetraploid is a priority for rice breeding. Microsatellites or simple sequence repeats (SSRs) are the widely used marker for estimating genetic diversity in many species, including wild, weedy, and cultivated rice. In our research, genetic diversity and population genetic structure of autotetraploid and diploid populations collected from Chengdu Institute of Biology, Chinese Academy of Sciences were studied based on 36 microsatellite loci. For the total of 50 varieties, a moderate to high level of genetic diversity was observed at population levels with the number of alleles per locus (Ae) ranging from 2 to 6 (mean 3.028) and PIC ranging from 0.04 to 0.76 (mean 0.366). The expected heterozygosity (He) varied from 0.04 to 0.76 with the mean of 0.370 and Shannon’s index (I) ranging from 0.098 to 1.613 (mean 0.649). The autotetraploid populations showed a slightly higher level of effective alleles, the expected heterozygosity and Shannon’s index than that of diploid populations. Rare alleles were observed at most of the SSR loci in one or more of the 50 accessions and core fingerprint database of the autotetraploid and diploid rice was constructed. The F-statistics showed that genetic variability mainly existed among autotetraploid populations rather than among diploid populations (Fst=0.066). Cluster analysis of the 50 accessions showed four major groups. Group I contained all of the autotetraploid and diploid indica maintainer lines and a autotetraploid and its original diploid indica male sterile lines. Groups II contained only original of IR accessions. Group III was more diverse than either group II or IV and comprised of both autotetraploid and diploid indica restoring lines. Group IV included japonica cluster of the autotetraploid and diploid rices. Furthermore, genetic differences at the single-locus and two-locus levels, as well as components due to allelic and gametic differentiation, were revealed between autotetraploid and diploid varieties. This analysis indicated that the gene pools of diploid and autotetraploid rice are somewhat dissimilar, which made a variation that distinguishes autotetraploid from diploid rices. Using this variation, we can breed new autotetraploid varieties with some new important agricultural characters but the diploid rice has not. Cytogenetic characteristics in restorer lines DTP-4, DMinghui63 and maintainer line D46B of autotetraploid rices were studied. DTP-4, DMinghui63 and D46B showed the advantage of high seed set and biological yield. The meiotic chromosome behavior was slightly irregular in DTP-4, DMinghui63 and D46B. We observed less univalent, trivalent and multivalent at MI, but more bivalent and quadrivalent were observed. The most frequent chromosome configurations were 12II 6IVand 10II 7IV in restorer and maintainer lines, respectively. The quadrivalent frequency of DTP-4 and Dminghui63 at metaphase(MI) was respectively 2.00/PMC and 2.26/PMC. However that frequency of D46B was 6.00/PMC, which was greatly significantly higher than DTP-4 and Dminghui63. That indicates the maintainer D46B has better chromosome pairing capability in metaphase (MI). The frequency of lagging chromosomes of the maintainer D46B at anaphaseI (AI) was 10.62%, which was significantly lower than that of DTP-4(19.44%) and Dminghui63(23.14%) and nearly reaching the level of diploid CK(7.30%). In telophaseI (TI) maintainer D46B showed lower frequency of microkernel at TI and lower frequency of abnormal spores at telophaseII(TII). We also studied pollen fertility, seed set and cytogenetic characteristics of restorer lines and F1 hybrids of autotetraploid rice. DTP-4, DMinghui63, D46A´DTP-4 and D46A´DMinghui63 showed significantly higher pollen fertility and seed set than DShixiang and D46A´DShixiang. Pairing configurations in PMC of DTP-4, DMinghui63, DShixiang, D46A´DTP-4, D46A´DMinghui63 and D46A´DShixiang were 0.05 I+19.96 II (9.89 rod+10.07 ring)+0.01 III+2.20 IV, 0.11 I+19.17 II (8.90 rod+10.37 ring)+0.09 III+2.26 IV+0.01 VI, 1.33 I+9.46 II (4.50 rod+4.96 ring)+0.44 III+6.02 IV+0.09 VI+0.09 VIII, 0.02 I+14.36 II (6.44 rod+7.91 ring)+0.01 III+4.80 IV+0.01V III, 0.06 I+17.67 II (11.01 rod+6.67 ring)+0.06 III+3.10 IV+0.01 VI and 1.11 I+11.31 II (5.80 rod+5.51 ring)+0.41 III+5.63 IV+0.03 VI+0.03 VIII, respectively. Configuration 16 II+4 IV and 12 II+6 IV occurred in the highest frequency among the autotetraploid restorers and hybrids. Meiotic chromosome behaviors were less abnormal in the tetraploids with high seed set than those with low seed set. The hybrids had fewer frequencies of bivalents, univalents, trivalents and multivalents than the restorers, but higher frequency of quatrivalents than the restorers at MI. The frequency of univalents at M1 had the most impact on pollen fertility and seed set, i.e., pollen fertility decreased with the increase of univalents. The secondary impact factors were trivalents and multivalents, and bivalents and quatrivalents had no effect on pollen fertility and seed set. The correlative relationship between pollen fertility and cytogenetic behaviors could be utilized to improve seed set in autotetraploidy breeding. The amylose content of autotetraploid indica mutant Rice D4063-1 dropped by half than diploid Minghui 63, that is, its amylose content of 5.23%.The whole sequence of Waxy gene of D4063-1 is amplified and sequenced. And the discrepancy of bases is found comparing to the reported Waxy gene. The Waxy gene of autotetraploid Rice D4063-1 had a base deletion in exon sequence, which resulted frameshift mutation in exon 9 and termination codon occur early. The mutation of Wx also led to the change of some common restriction endonuclease sites. Results showed compared to indica and japonica, D4063-1 had two adding sph1 sites. Compared to japonica, D4063-1 had six decreasing Acc1, a adding Xho1, Pst1 and Sal1 restriction sites. Phylogeny analysis shows that the DNA sequence of Waxy gene of D4063-1 is closer to Indica, and we suppose that the Waxy gene of D4063-1 is origin from genotype Wxa. In addition, according to the base differences of Wx in D4063-1, we deduce that RNA processing obstacle led by base change of intron is the main cause to low the amylose content, and related to phenotype of its soft rice. Based on analysis of fragments of D4063-1, indica and japonica and according to the special point of the three species, primers as markers-AUT4063-I were designed for distinguishing the D4063-1 from other rice. Combining with primer pair F5, dominant and codominant ways were established for discriminating them., rapid and correct identification of D4063-1 from other rice could be done. The genetic analysis is important to ensure the original of autotetraploid rice, for maintaining the “distinctiveness” of autotetraploid varieties, and to differentiate between the various genetic background of autotetraploid rice. The autotetraploid breeding will benefit from detailed analysis of genetic diversity in the germplasm collections. Further investigation on mechanisms of meiotic stability should benefit polyploid breeding. These findings demonstrated opportunity to improve meiotic abnormalities as well as grain fertilities in autotetraploid rice.

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作物的抗旱性是一个多基因控制的、极为复杂的数量性状,植物对干旱在分子水平上的差异反应通过植物组织生理和细胞生物学水平,最终表现为植物抗旱性的不同。在我国,旱地农业超过耕地面积的50%,但水资源短缺,因此培育和选育抗旱高产作物是发展节水型农业最有效的途径。 青藏高原气候恶劣、年均降雨量少,也是世界大麦初生起源中心,因而蕴藏了十分丰富的与抗逆相关的种质资源材料,从这些特殊的资源材料克隆抗旱基因,不仅对培育抗旱、优质、高产大麦新品种具有重要理论意义和经济价值,而且对整个作物抗旱基础和育种应用研究都具重大促进作用。 为了筛选青稞(裸大麦,Hordeum vulgare ssp. vulgare)抗旱性材料,本研究选用来自青藏高原不同地区的84份青稞为材料,在叶片失水率(water loss rate, WLR)检测分析的基础上,选择失水率值差异显著的12个品种,通过相对含水量(relative water content, RWC)和反复干旱法评价其抗旱性,并通过植株对干旱胁迫下的丙二醛(MDA)含量和游离脯氨酸(free-proline)含量变化,了解不同抗旱性材料的生理反应特性。选择抗旱性强弱不同的品种各两份进行LEA2蛋白基因(Dhn6基因)、LEA3蛋白基因(HVA1基因)的克隆,比较LEA蛋白结构差异与作物抗旱性之间的关系。同时,对抗旱性不同的青稞品种受到干旱时间不同的失水变化率(dynamics water loss rate, DWLR)进行了检测;对抗旱性不同的青稞对照材料进行2 h、4 h、8 h和12 h的快速干旱处理,通过SYBR Green实时荧光定量RT-PCR技术对Dhn6基因、Dhn11基因、Dhn13基因和HVA1基因在不同抗旱性材料受到不同干旱时间处理后的相对表达水平进行了检测。本研究对LEA蛋白基因在抗旱性不同的青稞材料中的干旱胁迫分子水平上的差异反应进行了研究,也对植物的抗旱机理进行了初步探讨。主要研究结果如下: 1. 青稞苗期进行离体叶片失水率测定结果表明,来自青藏高原的84份青稞材料的WLR在0.086~0.205gh-1g-1DW之间。选择WLR低于0.1gh-1g-1DW和WLR高于0.18gh-1g-1DW的品种各6份,并对苗期分别进行未干旱及干旱12小时的处理。相对含水量检测结果表明,低失水率青稞材料干旱后的具有更高的相对含水量,盆栽缺水试验也显示叶片失水率低的材料耐旱能力强于失水率高的材料。通过水合茚三酮法测定离体叶片游离脯氨酸的含量,结果表明,所有品种未干旱处理时,游离脯氨酸含量差异不大(17.10~25.74 µgg-1FW);干旱12小时后,低失水率的品种游离脯氨酸含量明显增高(32.99~53.45µgg-1FW),高失水率品种的游离脯氨酸含量与干旱前变化不明显(P<0.05)。硫代巴比妥酸法测定离体叶片丙二醛(MDA)含量,结果显示,12份所选对照品种中,丙二醛的含量在0.97~2.74nmolg-1FW,干旱12小时后丙二醛的含量显著上升(1.46~4.74nmolg-1FW),高失水率的6个品种的丙二醛含量在未干旱和干旱处理时都明显高于低WLR品种。本研究结果表明青稞的低失水率、低丙二醛含量、高相对含水量和高脯氨酸含量具相关性(P<0.05)。综上研究,我们认为作物失水率的测定可以作为快速检测作物抗旱性的指标之一,因此,强抗旱品种喜玛拉10号(TR1)、品比14号(TR2)和弱抗旱品种冬青8号(TS1)、QB24 (TS2)被选作抗旱基因克隆和表达分析的研究材料。 2. 高等植物胚胎发育晚期丰富蛋白(late embryogenesis abundant proteins, LEA proteins)与植物耐脱水性密切相关,为了探讨青稞LEA蛋白结构差异性与植物抗旱性的关系,本研究以强抗旱品种(喜玛拉10号、品比14号)和弱抗旱品种(冬青8号、QB24)为材料,利用同源克隆法,通过RT-PCR,分别克隆了与抗旱性密切相关的Dhn6基因和HVA1基因。Dhn6基因序列分析结果表明,强抗旱品种品比14号和弱抗旱品种冬青8号Dhn6基因所克隆到的序列为1026bp,它们之间只有5个碱基的差异;喜玛拉10号和QB24克隆到的序列长963bp。在强弱不同的抗旱品种中有22个核苷酸易突变位点,相应的脱水素氨基酸序列推导结果表明,22个核苷酸突变位点中,仅有8个位点导致相应的氨基酸残基的改变,其余的位点系同义突变,另外,21个富含甘氨酸序列的缺失并没有联系作物抗旱性特征。推测这些同义突变位点的氨基酸残基对维持青稞DHN6蛋白的正常结构和功能起着非常重要的作用,也可能DHN6蛋白对青稞长期适应逆境胁迫和遗传进化的结果。对HVA1基因的序列分析结果表明,冬青8号、QB24、品比14号和喜玛拉10号的目的基因核苷酸序列全长分别为661bp、697bp、694bp和691bp,它们都包含1个完整的开放阅读框。相应的LEA3蛋白氨基酸序列结果表明,11个高度保守的氨基酸残基组成基元重复序列的拷贝数与青稞抗旱性之间没有必然关系,在强抗旱品种(喜玛拉10号、品比14号)中三个共同的氨基酸突变位点Gln32、Arg33和Ala195可能对抗旱蛋白的结构和功能有影响;另外,强抗旱青稞品种LEA3蛋白质中11-氨基酸保守基元序列拷贝数和极性氨基酸占蛋白的比例更高,推测LEA3蛋白中基元序列拷贝数和极性氨基酸占蛋白的比例对该蛋白的结构和功能影响更大。 3. LEA蛋白基因的表达水平的上调与植物的耐脱水性密切相关,我们对强抗旱性材料(喜玛拉10号、品比14号)和弱抗旱材料(冬青8号、QB24)进行干旱处理2 h、4 h、6 h、8 h和10 h的失水变化率进行测定,结果表明弱抗旱品种在2~4小时之间失水率变化最明显,而四个对照品种的失水率在8小时后和24小时的失水率值变化不大。进一步提取青稞苗期进行2 h、4 h、8 h和12 h的干旱处理后的总RNA,通过SYBR Green实时荧光定量RT-PCR技术对青稞脱水素基因(Dhn6、Dhn11和Dhn13)和LEA3蛋白基因(HVA1)的相对表达水平受干旱时间和作物抗旱性的影响进行了检测。研究发现,抗旱性不同的青稞品种随干旱处理的时间延长,Dhn6、Dhn11、Dhn13和HVA1基因的相对表达水平不同。 Dhn6基因的相对表达水平在强抗旱青稞品种干旱8小时后快速上升,但在弱抗旱青稞品种干旱处理12小时后检测到更高表达量;Dhn11基因在对照青稞抗旱品种的表达累积水平随干旱时间的延长持续下降;整个干旱过程中,Dhn13基因的相对表达水平在弱抗旱品种持续上升,在强抗旱品种中干旱处理8小时快速上升并达到最高,干旱12小时后降低。与脱水素基因相比较,强抗旱青稞品种在干旱2小时后HVA1基因的相对表达水平显著升高,相对表达量随干旱处理的时间持续上升,在干旱12小时后达到最高;与之相比较,在整个干旱过程中,弱抗旱品种的相对表达水平显著低于强抗旱品种,在干旱8小时之前弱抗旱品种的相对表达水平变化不明显;在干旱8~12小时后却显著上升。上述结果表明,不同的LEA蛋白在植物耐脱水过程中的干旱表达累积水平不同;干旱不是诱导高等植物Dhn11基因表达的主要因素;植物的抗旱性不同,不同LEA蛋白基因对干旱的反应有差异。推测某些LEA蛋白基因的干旱胁迫早期表达累积程度与植物的抗旱性直接相关;其中,Dhn11基因和Dhn12基因不同的表达模式可能与干旱调控表达顺式作用成分(dehydration responsive element, DRE)的有无或结构上的差异有关。 本研究结果认为,(1)失水率和相对含水量可作为植物抗旱性检测的指标之一;(2) DHN6同义突变位点的氨基酸残基对维持该蛋白的正常结构和功能起着重要作用;(3) 11-氨基酸保守基元序列拷贝数和极性氨基酸的比例对LEA3蛋白结构和功能有重要影响;(4)LEA蛋白表达随着干旱胁迫程度而增加,但Dhn11基因并不受干旱诱导表达;(5)作物的抗旱性不同,LEA蛋白对干旱的累积反应并不相同,干旱早期LEA蛋白的累积程度可能会影响植物的抗旱性。 Drought resistance was a complex trait which involved multiple physiological and biochemical mechanisms and regulation of numerous genes. Because its complex traits, it is difficult to understand the mechanisms of drought resistance in plants. Plants respond to water stress through multiple physiological mechanisms at the cellular, tissue, and whole-plant levels. Tibetan hulless barley, a pure line, is a selfing annual plant that has predominantly penetrated into the Qinghai-Tibetan Plateau and remains stable populations there. The wide ecological range of Tibetan hulless barley differs in water availability, temperature, soil type and vegetation, which makes it possess a high potential of adaptive diversity to abiotic stresses. This adaptive genetic diversity indicates that the potential of Tibetan hulless barley serves as a good source for drought resistance alleles for breeding purposes. 12 contrasting drought-tolerant genotypes were selected to measure relative water content (RWC), maldondialdehyde (MDA) and proline content, based on values of water loss rate (WLR) and repeated drought methods from Tibetan populations of cultivated hulless barley. As a result of the screening, sensitive and tolerant genotypes were identified to clarify relationships between characteristics of LEA2/LEA3 genes sequences and expression and drought-tolerant genotypes, associated with resistance to water deficit. In addition, dynamics water loss rate (DWLR) was measured to observe the changes on diffrential drought-tolerant genotypes. Real-time quantitative RT-PCR was applied to detect relative expression levels of Dhn6, Dhn11, Dhn13 and HVA1 genes in sensitive and tolerant genotypes with 2 h, 4 h, 8h and 12 h of dehydration. In the present study, differential sequences and expression of LEA2/LEA3 genes were explored in Tibetan hulless barley, associated with phenotypically diverse drought-tolerant genotypes. 1. The assessments of WLR and RWC were considered as an alternative measure of plant water statues reflecting the metabolic activity in plants, and the parameters of MDA and proline contents were usually consistent with the resistance to water stress. The values of detached leaf WLR of the tested genotypes were highly variable among 84 genotypes, ranging from 0.086 to 0.205 g/h.g DW. The 12 most contrasting genotypes (6 genotypes with the lowest values of WLR and 6 genotypes with the highest values of WLR) were further validated by measuring RWC, MDA and free-proline contents, which were well watered and dehydrated for 12 h. Results of RWC indicated that the values of 12 contrasting genotypes RWC ranged from 89.94% to 93.38% under condition of well water, without significant differences, but 6 genotypes with lower WLR had higher RWC suffered from 12 h dehydration. The results indicated that lower MDA contents, lower scores of WLR and higher proline contents were associated with drought-tolerant genotypes in hulless barley. Remarkably, proline amounts were increased more notable in 6 tolerant genotypes than 6 sensitive genotypes after excised leaves were dehydrated for 12 h, with control to slight changes under condition of well water. Results of MDA contents showed that six 6 tolerant genotypes had lower MDA contents than the 6 sensitive genotypes under both stressed and non-stressed conditions. As a result of that screening, drought- resistant genotypes (Ximala 10 and Pinbi 14) and drought-sensitive genotypes (Dongqing 8 and QB 24) were chosen for comparing the differential characteristics of LEA2/LEA3 genes and their expression analysis. It was conclusion that measurements of WLR could be considered an alternative index as screening of drought-tolerant genotypes in crops. 2. Late embryogenesis abundant (LEA) proteins were thought to protect against water stress in plants. To explore the relationships between configuration of LEA proteins and phenotypically diverse drought-tolerant genotypes, sequences of LEA genes and their deduced proteins were compared in Tibetan hulless barley. Results of comparing Dhn6 gene in Ximala 10 and QB24 indicated that absence of 63bp was found, except that only 5 mutant nucleotides were found. While 22 mutant sites were taken place in Dhn6 gene between sensitive and tolerant lines, 14 synonymous mutation sites appeared in the contrasting genotypes. The additional/absent polypeptide of 21 polar amino acid residues was not consistent with phenotypically drought-tolerant genotypes in hulless barley. It was deduced that synonymous mutation sites would play important roles in holding out right configurations and functions on DHN6 protein. The sequencing analysis results indicated that each cloned HVA1 gene from four selected genotypes contained an entire open reading frame. The whole sequence of HVA1 gene from Dongqing 8, QB24, Pinbi 14 and Ximala 10 was respectively 661bp, 697bp, 694bp and 691bp. Results of DNA sequence analyses showed that the differences in nucleotides of HVA1 gene in sensitive genotypes were not consistent with that of tolerant genotypes, except for absence of 33 nucleotides from +154 to +186 (numbering from ATG) in QB24. Database searches using deduced amino acid sequences showed a high homology in LEA3 proteins in the selected genotypes. Multiple sequence alignments revealed that LEA3 protein from Dongqing 8 was composed of 8 repeats of an 11 amino acid motif, less the fourth motif than Pinbi 14, Ximala 10 and QB24. Consistent mutant amino acid residues appeared in contrasting genotypes by aligning and comparing the coding sequence region, including Gln32, Arg33 and Ala195 in tolerant genotypes as compared to Asp32, Glu33 and Thr195 (Thr184 in Dongqing 8) in sensitive lines. It was concluded that consistent appearance of Gln32, Arg33 and Ala195 would contributed to functions of LEA3 protein in crops, as well as higher proportion of 11-amino-repeating motifs and polar amino acid residues. 3. Most of the LEA genes are up-regulated by dehydration, salinity, or low temperature, are also induced by application of exogenous ABA, which increases in concentration in plants under various stress conditions and acts as a mobile stress signal. Higher levels of proteins of LEA group 3 accumulated was correlated well with high level of desiccation tolerance in severely dehydrated plant seedlings. Dehydrins (DHNs), members of LEA2 protein, are an immunologically distinct protein family, and Dhn genes expression is associated with plant response to dehydration. Dynamic water loss rate was measured between sensitive genotypes and tolerant genotypes after they were dehydrated for 2 h, 4 h, 6h and 8 h. Detailed measurements of WLR at the early stage of dehydration (2, 4, 6, and 8 h) showed that WLR was stabilizing after 8 h, and there were no significant changes between these values and WLR after 24 h. Drought stress was applied to 10-day-old seedlings by draining the solution from the container for defined dehydration periods. Leaf tissues of the selected genotypes were harvested from control plants (time 0); and after 2, 4, 8, and 12 h of dehydration. Differential expression trends of Dhn6, Dhn11, Dhn13 and HVA1 genes were detected in phenotypically diverse drought-tolerant hulless barleys, related to different time of dehydration. Results of quantitative real-time PCR indicated that relative level of HVA1 expression was always higher in tolerant genotypes, rapidly increasing at the earlier stages (after 2-4 h of dehydration). However, HVA1 expressions of sensitive genotypes had a fast increase from 8 h to 12 h of stress. Significant differences in expression trends of dehydrin genes between tolerant genotypes and sensitive lines were detected, mainly in Dhn6 and Dhn13 gene, depending on the duration of the dehydration stress. The relative expression levels of Dhn6 gene were significantly higher in tolerant genotypes after 8 h dehydration, by control with notable higher expression levels after 12 h water stress in sensitive ones. The relative expression levels of Dhn13 gene tended to ascend during exposure to dehydration in drought-sensitive genotypes. However, fluctuate trends of Dhn13 expression level were detected in drought-resistant lines, including in lower expression levels of 12 h dehydration as compared to 8 h water stress. It was conclusion that (1) diverse LEA proteins would play variable roles in resisting water stress in plants; (2) expression of Dhn11 gene was not induced by dehydrated signals because of the trends of expression descended in contrasting genotypes suffered from water deficit and (3) variable accumulations on LEA proteins would be appear in diverse drought-tolerant genotypes during dehydrations. It is deduced that higher accumulations of Dhn6 and Dhn13 expression in 8 h dehydration are related to diverse drought-tolerant lines in crops. The present results indicated that different dehydrin genes would play variable functional roles in resisting water stress when plants were suffered from water deficit. The authors suggest physiologically different reactions between resistant and sensitive genotypes may be the results of differential expression of drought-resistant genes and related signal genes in plants. In addition, contrarily induced expression of Dhn11 and Dhn12 was related to dehydration responsive element (DRE) in barleys. The present study indicated that (1) measurements of WLR and RWC could be considered as one index of drought-tolerant screenings; (2) synonymous mutation sites would play important roles in holding out right configurations and functions on DHN6 protein, (3) higher proportion of 11-amino-repeating motifs and polar amino acid residues would contribute to functions on LEA3 protein, (4) the longer drought, the more accumulation on LEA proteins, except for Dhn11 gene in crops and (5) differential responses on expression of LEA protein genes would result in physiological traits of drought tolerance in plants.

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高等植物种子胚乳贮藏蛋白是种子发芽时的主要氮源,也是人类和动物食用植物蛋白的主要来源。大麦种子胚乳贮藏蛋白主要是醇溶蛋白(hordeins),占大麦胚乳总蛋白的50–60%。根据大麦醇溶蛋白的大小和组成特点,大麦醇溶蛋白被划分为三种类型:富硫蛋白亚类(B,γ-hordeins)、贫硫蛋白亚类(C-hordeins)以及高分子量蛋白亚类(D-hordeins)。B组和C组醇溶蛋白是大麦胚乳的两类主要贮藏蛋白,它们分别占大麦总醇溶蛋白成分的70–80%和10–12%。遗传分析表明,大麦B、C、D和γ-组醇溶蛋白分别是由位于大麦第五染色体1H(5)上的Hor2、Hor1、Hor3和Hor5位点编码。Hor2位点编码大量分子量相同但组成不同的B组醇溶蛋白(B-hordein)。B-hordein的种类、数量和分布是影响大麦酿造、食用及饲养品质的重要因素之一。为深入了解B-hordein基因家族的结构和染色体组织,探明Hor2位点基因表达的发育调控机制,最终达到改良禾谷类作物籽粒品质的目的,本研究以青藏高原青稞为材料,采用同源克隆法,分别克隆B-hordein基因和启动子,通过原核生物表达验证B-hordein基因功能,并利用实时定量PCR探索B-hordein基因表达时空关系,取得如下研究结果: 1. 以具有特殊B组醇溶蛋白亚基组成的9份青藏高原青稞为材料,根据GenBank中三个B-hordein基因序列(GenBank No. X03103, X53690和X53691)设计一对引物,通过PCR扩增,获得23个B-hordein基因克隆并对其进行了序列分析。核苷酸序列分析表明,所有克隆均包含完整的开放阅读框。有11个克隆都存在一个框内终止密码子,推测这11个克隆可能是假基因。推测的氨基酸序列分析表明,所有大麦B-hordein具有相似的蛋白质基本结构,均包括一个高度保守的信号肽、中间重复区以及C-端结构域。不同大麦种重复区内重复基元的数目有较大差异。青稞材料Z07–2和Z26的B-hordeins仅具有12个重复基元结构,更接近于野生大麦。这些重复基元数目的差异导致了重复区序列长度和结构的变异。这种现象极可能是由于醇溶谷蛋白基因在进化过程中染色体的不平衡交换或复制滑动所造成的。对所克隆基因和禾本科代表性醇溶谷蛋白基因进行聚类分析,结果表明所有来自栽培大麦的B-hordeins聚类成一个亚家族,来自野生大麦的B-hordeins以及普通小麦的LMW-GS聚类成另外一个亚家族,表明这两个亚家族的成员存在显著差异。此外,我们发现B-hordein基因推测的C-末端序列具有一些有规律的特征:即具有相同C-末端序列的B-hordein基因在系统发生树中聚类为同一个亚组(除BXQ053,BZ09-1,BZ26-5分别单独聚为一类外)。这个特征将有助于我们对所有B组醇溶蛋白基因家族成员进行分类,避免了在SDS-PAGE电泳图谱上仅依靠大小分类的局限性。 2. 根据上述克隆的青稞B-hordein基因的5’端序列设计三条基因特异的反向引物,以青稞Z09和Z26的基因组DNA为模板,采用SON-PCR和TAIL-PCR技术分离克隆出8个B-hordein基因的上游调控序列(命名为Z09P和Z26P)。序列分析表明,推测的TATA box位于–80 bp,CAAT–like box位于–140 bp处。此外,Z09P和Z26P中有六个序列在–300 bp处均存在一个由高度保守的EM基序和类GCN4基序构成的胚乳盒(Endosperm Box,EB),在约–560 bp处存在一个胚乳盒类似结构。而Z09P-2和Z26P-3不存在保守的胚乳盒或其类似结构,预示着这两个启动子所调控的基因表达可能受不同类型反式作用因子的调节,推测该启动子对基因的表达调控具有多样性。 3. 将B-hordein基因的开放阅读框定向克隆到表达载体pET-30a中,将其导入大肠杆菌表达菌株BL21中进行外源基因的诱导表达以验证所克隆基因的功能。结果表明仅含重组子pET-BZ07-2和pET-BZ26-5的BL21细菌有目的表达蛋白产生。在诱导3 h时的蛋白表达量最高;3 mM IPTG诱导的蛋白表达量要高于1 mM IPTG诱导的表达量。这为分离纯化B-hordein蛋白以及进一步研究其对大麦籽粒品质的影响奠定基础。 4. 根据从青稞Z09和Z26中分离克隆的B-hordein基因序列设计一对基因特异的引物,同时,选择大麦α-微管蛋白基因(GenBank no. U40042)为看家基因并设计特异引物,利用实时荧光定量PCR检测了青稞籽粒4个胚乳发育时间段的B-hordein基因表达,荧光定量结果显示:两份材料中B-hordein基因的表达量均随发育过程的进行而逐渐升高。Z09中B-hordein基因在开花后7天开始转录,而Z26开花4天后就有低水平B-hordein的表达,这表明Z26中B-hordein基因可能比Z09表达的较早或者Z09中B-hordein基因表达水平较低以致于不能被检测到。此外,在4个不同的胚乳发育时期中,Z26中B-hordein基因的表达量均高于Z09材料。在开花12天到18天的过程中,Z09和Z26中B-hordein基因的表达水平有一个急剧性的升高。这说明在不同胚乳发育时期,Hor2位点的B-hordein等位基因变异体存在mRNA的差异表达。 Seed endosperm storage proteins in higher plants are the main resources of nitrogen for germinating and plant proteins for human and animals. Barley prolamins (also called hordeins) are the major storage proteins in the endosperm and account for 50–60% of total proteins. Hordeins are classically divided into three groups: sulphur-rich (B, γ-hordeins), sulphur-poor (C-hordeins) and high molecular weight (HMW, D-hordeins) hordeins based on the size and composition. B-hordeins and C-hordeins are two major groups and each respectively account for about 70-80% and 10-12% of the total hordein fraction in barley endosperm. Genetic analysis showed that B-, C-, C-, γ-hordeins are encoded by Hor2, Hor1, Hor3 and Hor5 locus on the chromosome 1H (5). Hor2 locus is rich in alleles that encode numerous heterogeneous B-hordein polypeptides. It is reported that B-hordein species, quantity and distribution are significant factors affecting malting, food and feed quality of barley. To understand comprehensively the structure and organization of B-hordein gene family in hull-less barley and explore the developmental control mechanisms of Hor2 locus gene expression and eventually to better exploitation in crop grain quality improvement, we isolated and cloned B-hordein genes and promotors of hull-less barley from Qinghai-Tibet Plateau by PCR, and testified their expression founction in bacteria expression system and explore their spatial and temporal expression pattern by quantitative real time PCR. Our results are as followed, 1. Twenty-three copies of B-hordein gene were cloned from nine hull-less barley cultivars of Qinghai-Tibet Plateau with special B-hordein subunits and molecularly characterized by PCR, based on three B-hordein genes published previously (GenBank No. X03103, X53690 and X53691). DNA sequences analyses confirmed that the six clones all contained a full-length coding region of the barley B-hordein genes. Eleven clones all contain an in-frame stop codon and they are probably pseudogenes. The analysis of deduced amino acid sequences of the genes shows that they have similar structures including signal peptide domain, central repetitive domain, and C-terminal domain. The number of the repeats was largerly variable and resulted in polypeptides in different sizes or structures among the genes. Twelve such repeated motifs were found in Z07–2 and Z26, and they are close to those of the wild barleys, and it is most probably caused by unequal crossing-over and/or slippage during replication as suggested for the evolution of other prolamins. The relatedness of prolamin genes of barley and wheat was assessed in the phylogenetic tree based on their polypeptides comparison. Our phylogenetic analysis suggested that the predicted B-hordeins of cultivated barley formed a subfamily, while the B-hordeins of wild barleys and the two most similar sequences of LMW-GS of T. aestivum formed another subfamily. This result indicated that the members of the two subfamilys have a distinctive difference. In addition, we found the B-hordeins with identical C-terminal end sequences were clustered into a same subgroup (except BXQ053,BZ09-1 and BZ26-5 as a sole group, respectively), so we believe that B-hordein gene subfamilies possibly can be classified on the basis of the conserved C-terminal end sequences of predicted polypeptide and without the limit of SDS-PAGE protein banding patterns. 2. The specific primers were designed according to the published sequences of barley B-hordein genes from Z09 and Z26. Using total DNA isolated from them as the templates, eight clones (designated Z09Pand Z26P) of upstream sequences of the known B-hordein genes was obtained by TAIL-PCR and SON-PCR. Sequences analysis shows that the putative TATA box was present at position –80 bp and CAAT-like box at position –140 bp. Besides, a putative Endosperm Box including an Endosperm Motif (EM) and a GCN4-Like Motif was found at position –300 bp in six clones, and another Endosperm-like box was found at positon –560 bp. While the Endosperm Box or Endosperm-like box was not found in Z09P-2 and Z26P-3. This may indicate that gene expression drived by the two promtors was probably controlled by different trans-acting factors and the genetic control mechanism of corresponding gene expression may be diverse. 3. The B-hordein genic region coding for the mature peptide was cloned into expression vector pET-30a and transformed into bacterial strain BL21 for identifying gene expression fountion. Protein SDS–PAGE analysis showed that only the transformed lysate with the pET-BZ07-2 and pET-BZ26-5 constructs produced proteins related to B-group hordeins of barley, and the mounts of proteins induced by 3 mM IPTG and 3 h were higher than other conditions. This established a base for isolating and putifying B-hordein and further exploring their effects on barley grain quality. 4. The gene-specific primers of B-hordein genes from Z09 and Z26 were used for the quantification of B-hordein gene expression. The α-tubulin gene from Hordeum vulgare subsp. vulgare (GenBank accession number U40042) was used as a control gene. The result shows the transcription of the B-hordein genes in Z09 was found 7 days after flowering, while the transcription of the B-hordein genes in Z26 was found 4 days after flowering, but at a very low level, and it suggested that the B-hordein genes in Z26 probably expressed earlier than those in Z09, or the B-hordein genes in Z09 expressed at so a lower level than Z26 that it can not detected. In addition, B-hordein genes in Z26 accession showed higher expression levels than those in Z09 in four developing stages. Furthermore, a progressive increase in the expression levels of the B-hordein genes between 12 and 18 days after anthesis was observed in both Z09 and Z26. It implies that the B-hordein allelic variants encoded by Hor2 locus exist the differential expression in mRNA levels of during barley endosperm development.

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糯小麦在食品加工业、淀粉加工业及其它工业上有着重要用途,是近年来许多国家小麦研究的重要课题。国外糯小麦选育尚未突破高产与糯性相结合的难点,国内目前还没有培育出高蛋白强筋型的糯小麦品种,这在一定程度上与缺乏合适的育种方法和高效、实用的糯小麦分子标记辅助育种技术有关。国内外对Wx基因效应的研究主要利用缺体-四体系、重组自交系或近等基因系,还未见有利用遗传背景相同的BC5F2代回交改良群体的报道。 糯性位点近等基因系是小麦淀粉品质育种的重要材料,而我国目前还没有一套中国栽培小麦遗传背景的糯性位点近等基因系。为了选育部分糯小麦、全糯小麦和中国栽培小麦遗传背景的糯性位点近等基因系,我们利用Wx蛋白电泳和高效实用的分子标记技术体系来鉴定糯小麦杂交后代的基因型,结果证明该体系能有效地用于糯小麦的分子标记辅助育种。以中国春糯性位点全套近等基因系为研究材料,对小麦Wx基因的6个STS标记和1个CAPS标记进行了筛选,改良PCR扩增条件以及产物检测方式后,从这些标记中筛选出3个标记,包括鉴定Wx-A1、Wx-D1位点的2个共显性STS标记和Wx-B1位点的1个显性STS标记。利用上述3个分子标记从BC5F2 代回交改良群体中筛选出了8种Wx基因型,经卡方检验,其分离比符合3对基因的分离比例,其中基因型为aabbdd的植株有2株,直链淀粉含量分别为1.81%和0.82%,为全糯小麦;基因型为AAbbdd,aabbDD的部分糯性植株各有1株,直链淀粉含量分别为15.24%和17.57%。以上4株植株的农艺性状和品质性状接近回交亲本“川育12”,并明显优于全糯材料“98Y1441”,表明采用回交法与Wx基因分子标记辅助选择相结合,有助于培育高产、优质的全糯和部分糯小麦。同时,本研究中建立的分子标记技术体系,也为选育具有中国栽培小麦遗传背景的糯性位点近等基因系奠定了基础。 在基因型鉴定的基础上,利用糯小麦杂交后代BC5F2代回交改良群体研究了各基因缺失降低直链淀粉含量的效果和各基因合成直链淀粉的能力,以及直链淀粉含量与农艺性状、品质性状、淀粉糊化特性等的相关性。缺失不同Wx基因的8种基因型,直链淀粉含量差异显著。研究单缺失基因型发现,减少效应最大的是Wx-B1b基因,Wx-B1b和Wx-D1b基因没有显著差异,减少效应最小的是Wx-A1b基因。研究双缺失基因型发现,Wx基因合成直链淀粉的能力,Wx-B1a基因最高,Wx-A1a基因最低,而Wx-B1a和Wx-D1a基因差异很小;直链淀粉含量与株高、穗长、小穗数、穗粒数、千粒重等农艺性状相关不显著,表明淀粉品质育种可以与高产育种实现有机结合;直链淀粉含量与SDS-沉降值呈显著负相关(r=-0.726),说明直链淀粉含量降低在一定程度上有利于提高小麦营养与加工品质,这一结果至今未见有文献报道;全糯类型的淀粉糊化特性与其他类型显著不同,具有最高的峰值粘度和稀懈值,最低的低谷粘度、最终粘度、反弹值、峰值时间、糊化温度、起始糊化温度,表明糯小麦淀粉在食品和工业上具有特殊用途;稀懈值与直链淀粉含量呈极显著负相关(r=-0.969),其他粘度参数与直链淀粉含量呈显著正相关(最终粘度r=0.797,低谷粘度r=0.910、反弹值r=0.954、峰值时间r=0.970、糊化温度r=0.962、起始糊化温度r=0.932)。以上结论可为糯小麦品种选育和淀粉品质改良提供理论依据。 Waxy wheat is very important in food processing industry, starch processing industry and the other industries, so it is a focus of wheat research in many countries these years. Foreign wheat breeders have not conquered the difficulty of high yield combined with waxy character, and there is no waxy wheat variety with high protein and strong gluten in China at present,all of which were caused by lacking proper breeding methods and effective, applied molecular markers-assisted selection technique at a certain extent. Until now, research about the effect of waxy genes mainly depended on nullisomic-tetrasomic lines, recombinant lines or near-isogenic lines, and it is lacking the reports of using improved BC5F2 backcross progenies under the common genetic background. Near-isogenic lines at the Wx loci are important materials for wheat starch quality breeding. However, there are no such lines under the Chinese cultivated wheat genetic background. To develop partial waxy wheats, waxy wheats and near-isogenic lines at the Wx loci under the Chinese cultivated wheat genetic background, we use SDS-PAGE of waxy proteins and effective, applied molecular marker-assisted selection technical system to identify the genotype of waxy wheat’s progenies. The results indicated that such a system is applicable in waxy wheat’s molecular marker-assisted selection effectively. A series of Chinese Spring Wx loci near-isogenic lines were used to identify the specific bands of six STS markers and one CAPS marker of Wx genes. After optimizing PCR amplification and separating of PCR products, three co-dominant and dominant STS-markers were identified at the Wx-A1, Wx-D1 and Wx-B1 loci, respectively, which were used to identify the genotype of waxy wheat’s progenies. Eight Wx genotypes were developed from the improved BC5F2 backcross progenies, which follows Mendelian segregation. Among them, there were two aabbdd waxy plants whose amylose content in the BC5F3 seeds were 1.81% and 0.82%, respectively. In addition, there were partial waxy plants (AAbbdd and aabbDD) whose amylose content in the BC5F3 seeds were 15.24 % and 17.57%, respectively. Most agronomic and quality traits of these four plants resembled those of the recurrent parent “Chuanyu 12”, and superior to waxy wheat parent “98Y1441”. This shows that backcross approach in combination with molecular marker-assisted selection of waxy genes is helpful to develop partial and full waxy wheat with good traits in the waxy wheat breeding program. At the same time, molecular marker-assisted selection technical system in this paper, also establish the base for breeding the near-isogenic lines at the Wx loci under the Chinese cultivated wheat genetic background. According to the results of genotype identification, we use waxy wheat’s improved BC5F2 backcross progenies to verify the effects of null alleles on reducing amylose content and determine the amylose synthesis capacity of each Wx gene independently, and investigate the relativity among amylose content with agonomic traits, quality traits, starch pasting properties respectively. There was significant difference in amylose content of the eight genotypes carrying different null Wx alleles. The reducing effect of the single null alleles was the most significant in Wx-B1b, followed by Wx-D1b and Wx-A1b, and there was no significant difference between Wx-B1b and Wx-D1b. The results of the double null lines further demonstrated that for the capacity of amylose synthesis, Wx-B1a was the highest, followed by Wx-D1a and Wx-A1a, and there was no significant difference between Wx-B1a and Wx-D1a. Amylose contents of the eight genotypes were not significantly correlated with plant height, spike length, spikelets per spike, grains per spike, 1000-grain weight, which showed that starch quality breeding could integrate with high yield breeding. Amylose contents of the eight genotypes were negatively significantly correlated with SDS-sedimentation value(r=-0.726), which suggested that reduction in amylose content is propitious to improve quality at a certain extent. Starch pasting properties of the full waxy type was significantly different from the other seven types, with the highest peak viscosity and breakdown, and lowest valley viscosity, final viscosity, setback, peak time, pasting temperature and starting pasting temperature. It indicated that waxy wheat starch has special use in food and industry. Breakdown was negatively significantly correlated with amylose contents (r=-0.969), and the other parameters were positively significantly correlated with amylose contents (r=0.797 for final viscosity, r=0.910 for trough viscosity, r =0.954 for setback, r =0.970 for peak time, r=0.962 for pasting temperature and r=0.932 for starting pasting temperature ). The results of the study are very useful for waxy wheat variety breeding and starch quality improvement.

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小麦加工品质改良已成为我国小麦育种的主要目标之一。特别是我国加入WTO以后,对小麦产品的质量提出了更高的要求,小麦品质改良的任务将更加艰巨和重要,小麦胚乳蛋白是影响小麦加工品质性状的重要因素。因此,深入了解小麦胚乳蛋白对加工品质性状的影响及其分子基础,为品质改良提供理论依据和科学指导,对加速我国小麦品质育种和优质小麦生产具有重要意义。本研究选用在麦谷蛋白5个基因位点(Glu-A1、Glu-B1、Glu-D1、Glu-B3和Glu-D3)上均含不同等位基因的小麦品种99G45和京771及Pm97034和京771杂交F9代共164个麦谷蛋白纯合系,及228个中国推广普通小麦品种和高代育成品系为试材,研究了麦谷蛋白Glu-1和Glu-3位点基因等位变异对籽粒蛋白、湿面筋含量、Zeleny沉降值和SDS沉降值间的关系;本研究还利用小麦A、B和D基因组中低分子量麦谷蛋白亚基(LMW-GS)基因特异引物,通过PCR方法克隆了1个Glu-A3位点和3个Glu-B3位点LMW-GS基因片段,在此基础上分析了不同等位基因对品质造成差异的分子基础;另外,本研究对中国近年推广的部分品种和育成的高代品系资源的多样性进行了分析。现将主要研究结果简述如下: 1. 对来自三个麦区的148份材料的醇溶蛋白组成进行了分析,结果表明,各麦区醇溶蛋白模式具有较大差异。在ω区,A7、B、E、F、G、J、P、Q、S和U仅存在于西南秋播麦区;A3、M、N、R、W和X仅存在于黄淮特种麦区;K仅存在于北方冬麦区;A6是北方冬麦区出现频率最高的带型模式,而西南秋播麦区中D出现的频率最高。ω-区的E、H和M几种模式是以前国内外未曾报道的。且初步确定,这些模式对品质性状具有正效应。至于γ区,A、B、D、E和F在各区均有出现,其中B和E在各区出现的频率都很高,在26.1-39.6%之间。相反,H 仅出现在黄淮特种麦区,J仅限于西南秋播麦区。对于β-区醇溶蛋白,B型模式在所有区中都相当高,而模式A仅存在于第三区.对于α-区,模式A在Ⅲ区而模式D在Ⅱ区出现的频率很高。1BL.1RS易位系在中国小麦品种中出现频率高达41.2%,在I, II和Ⅲ麦区的出现频率分别为 45.5、43.5和35.2%。各生态区模式的差异可能是品种适应不同生态条件和人为选择的结果,但这有待进一步证明。由于醇溶蛋白位点(Gli-1)与LMW-GS位点(Glu-3)紧密连锁,本结果可为下面确定普通小麦LMW-GS等位基因变异所用。 2. 利用Gli-1与Glu-3的紧密连锁,以228个小麦品种/系为材料,首次对中国小麦品种麦谷蛋白亚基的6个位点进行综合分析,研究小麦籽粒蛋白与品质性状间的关系,结果表明6个高分子量(HMW)和低分子量(LMW)麦谷蛋白位点对蛋白质含量的效应大小为,Glu-D1>Glu-B3>Glu-A1=Glu-B1> Glu-A3=Glu-D3;对GMP含量的效应大小为, Glu-A3>Glu-B3>Glu-D1> Glu-B1>Glu-A1>Glu-D3;对湿面筋含量的效应大小为, Glu-B1>Glu-B3= Glu-D3>Glu-A3>Glu-A1>Glu-D1;对Zeleny沉降值的效应大小为, Glu-A1> Glu-B3>Glu-D3>Glu-D1>Glu-B1>Glu-A3;对SDS沉降值的效应大小为, Glu-B3>Glu-A1=Glu-D1=Glu-A3>Glu-D3>Glu-B1。对蛋白含量而言,各位点的最佳组合方式为1、17+18、5+10、Glu-A3e、Glu-B3g、Glu-D3b;对湿面筋含量而言,各位点的最佳组合方式为1、6+8、5+10、Glu-A3d、Glu-B3c、Glu-D3b;对Zeleny沉降值而言,各位点的最佳组合方式为N、17+18、5+10、Glu-A3d、Glu-B3d、Glu-D3b;对SDS沉降值而言,各位点的最佳组合方式为1、7+8、2.2+12、Glu-A3b、Glu-B3g、Glu-D3b。另外,分析了稀有亚基对5+12与2.2+12与品质性状的关系,认为5+12对品质有负效应,2.2+12对品质有正效应。在品质育种时,应对优异组合或优异亚基加以利用。 3. 首次利用重组自交系(RILs)为材料,研究麦谷蛋白亚基表达量与品质性状的关系,通过对重组自交系中各HMW-GS表达量的分析,认为,就单个亚基的表达量而言,7亚基最高;其次为2亚基、5亚基、12亚基和10亚基;亚基9和1的表达量最小;N亚基不表达。对成对出现的亚基对而言,x型和y型亚基的总表达量2+12>5+10>7+9>17+18。就单个亚基与品质性状的关系而言,仅有10亚基的表达量与蛋白含量的相关性达5%的显著水平,2亚基的表达量与湿面筋含量呈负相关,显著水平也达5%,其余单个亚基对品质性状均无显著影响;就x型/y型亚基的比例来看,2/12和5/10对湿面筋含量都有显著的负效应;对某一位点等位基因控制的亚基表达总量来看,2+12对SDS沉降值有显著负效应。另外,本研究得出:2+12的亚基对的负效应主要体现在2亚基上,且在同一位点上,x型亚基的表达量大于y型。所以推导稀有亚基组合2+10很可能也是劣质亚基。 4. 以 Glu-A1、Glu-B1、Glu-D1、Glu-B3和Glu-D3作为5个因素对99G45/京771和Pm97034/京771杂交后代的蛋白质含量和SDS沉降值进行多因素方差分析。结果表明,Glu-A1和Glu-D3对蛋白含量的加性效应达5%显著水平;Glu-D1 * Glu-D3对蛋白质含量的互作效应也达5%显著水平;其余位点的加性和互作效应对蛋白质含量的影响均不显著。对SDS 沉降值而言,Glu-D1的加性效应最大,贡献率为4.2 % ,达1 %显著水平,其次是Glu-B1位点,贡献率为3.3% ,达5%显著水平。其余位点对SDS 沉降值的加性和互作效应均未达5%显著水平。总体而言, 各位点对蛋白含量的效应大小为Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3;对SDS沉降值的效应大小为Glu-D1>Glu-B1> Glu-D3>Glu-A1> Glu-B3。Glu-D1和Glu-D3位点上等位基因变异对蛋白含量有显著或极显著影响,含Glu-D1d和Glu-D3 GD、Glu-D3 JD基因的株系分别比含Glu-D1a和Glu-D3 PD基因的株系有较高的蛋白含量;在该遗传背景下,麦谷蛋白各基因位点对蛋白含量的效应大小依次排列为:Glu-A1位点1>N;Glu-B1位点7+9>17+18>14+15;Glu-D1位点5+10>2+12;Glu-B3位点GB>JB>PB;Glu-D3位点GB>JB>PB。对SDS沉降值的效应大小依次排列为:Glu-A1位点1>N;Glu-B1位点7+9=17+18>14+15;Glu-D1位点5+10>2+12;Glu-B3位点GB>JB>PB;Glu-D3位点GB>JB>PB。所以,对蛋白含量和SDS沉降值均较好的组合为1,7+9,5+10,GB,GD。 5. 因为GB和PB对品质的效应有显著差异,选取LMW-GS位点特异扩增引物对京771、99G45和Pm97034的Glu-B3位点进行扩增,结果得到三个不一样的扩增片段(Genebank号为DQ539657-DQ539659),得到的基因片段与Genebank中已报道的同类序列高度同源。通过克隆片段组成的分析,发现对Pm97034的序列较京771和99G45段少一个7氨基酸的重复单元,这可能是它较另外两个片段对面筋强度影响小的主要原因;另外,在99G45的序列中,124位处出现L(亮氨酸)代替P(脯氨酸),158位处出现了T(苏氨酸)代换M(蛋氨酸),这可能是99G45Glu-B3位点序列对SDS沉降值的效应显著优于Pm97034的原因。 6.通过对RILs各位点同普通小麦品种(系)各位点与品质关系的比较,发现对SDS沉降值的效应,各位点在不同研究材料中是不同的,普通小麦中:Glu-B3>Glu-A1=Glu-D1=Glu-A3>Glu-D3>Glu-B1,RILs中:Glu-D1>Glu-B1> Glu-D3>Glu-A1> Glu-B3。利用重组自交系材料(完全排除了1BL/1RS易位干扰)所得到的结果与Gupta and MacRitchie (1994)所得结论一致。进一步证实了1BL/1RS易位对小麦品质的重要影响。对蛋白含量而言,普通小麦品种(系)中,Glu-D1>Glu-B3>Glu-A1=Glu-B1> Glu-A3=Glu-D3,RILs中,Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3,和对SDS沉降值的效应一样,推断在非1BL/1RS易位的情况下,各位点对其效应应为Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3。 对同一位点的等位基因而言,普通小麦和重组自交系中Glu-A1和Glu-D1上的等位基因对品质性状的贡献是一致的,但Glu-B1上的等位基因对SDS沉降值的贡献发生了变化,普通小麦中17+18>7+9,RILs中7+9>17+18,这可能也是1BL/1RS造成的。 Baking quality improved is one of the main object of wheat bread in China. The overall objective of the present studies was to increase the understanding about protein quality in wheat, i.e. to make it possible to improve the production of wheat with desired quality for different end-uses. With the analysis of gluten protein in RILs, 99G45/Jing 771 and Pm97034/Jing, and 228 wheat cultivars or lines in China, the correlations between glutenin compositions and protein content, glutenin macropolymer(GMP), wet gluten content, Zeleny sedimentation value and SDS sedimentation value contentand breadmaking quality were studied. Also a rapid and efficient detection method of geneticpolymorphism at Glu-B3 loci in wheat was established using polymerase chain reaction(PCR).The results obtained were as follows: 1. Cultivated Chinese wheat germplasm has been a valuable genetic resource in international plant breeding. Patterns of gliadin among cultivated Chinese accessions are unknown, despite the proven value and potential novelty. The objective of this work was to analyse the diversity within improved Chinese wheat germplasm. The electrophoretic banding patterns of gliadin in common wheat cultivars and advanced lines were determined by acid-polyacrylamide gel electrophoresis. For 148 leading commercial cultivars and promising advanced lines used in our study, 48 patterns were identified, 29 corresponding to ω-gliadin, 9 to γ-gliadin, 5 to β-gliadin and 5 to α-gliadin. The most frequent patterns were A6 in ω; B in γ; B in β and A in the region of α. 116 band types appeared in the148 samples: 94 accessions had unique gliadin types, and 22 gliadin types while not unique were found in 54 accessions. The gliadin patterns of Chinese wheat cultivars and lines greatly differed from the patterns of wheat lines from other countries. Three patterns, E, J, H, M, N and O in the ω-zone had not previously been reported. Three wheat zones,the Northern Winter Wheat Region, the Yellow and Huai Valley River valleys Winter Wheat Region and the Southwestern Winter Wheat Region,in China showed different frequencies in their gliadin patterns. This information can be used to monitor genetic diversity with Chinese wheat germplasm. 2. To analyse the relationship between the loci and characteristics quality, we utilized the 228 cultivars/lines. The results showed that : For protein content, Glu-D1 >Glu-B3>Glu-A1=Glu-B1>Glu-A3=Glu-D3. For GMP content, Glu-A3>Glu-B3 >Glu-D1>Glu-B1>Glu-A1>Glu-D3. For wet gluten content, Glu-B1>Glu-B3= Glu-D3>Glu-A3>Glu-A1>Glu-D1. For Zeleny sedimentation value, Glu-A1>Glu-B3> Glu-D3>Glu-D1>Glu-B1>Glu-A3, For SDS sedimentation value, Glu-B3>Glu-A1= Glu-D1= lu-A3>Glu-D3>Glu-B1。For protein content, the best combination of 6 loci is (1,17+18,5+10,Glu-A3e, Glu-B3g,Glu-D3b). For wet gluten content, the best combination of 6 loci is (1,6+8,5+10,Glu-A3d,Glu-B3c,Glu-D3b). For Zeleny sedimentation value, the best combination of 6 loci is (N,17+18,5+10,Glu-A3d, Glu-B3d, Glu-D3b). For SDS sedimentation value, the best combination of 6 loci is(7+8,2.2+12,Glu-A3b, Glu-B3g,Glu-D3b)。Additional, we analysed the relationship between the subunits 5+12 and 2.2+12, think that 5+12 was negative for quality, 2.2+12 is postive for quality. It should be effective utilized. 3. It’s the first time to utilize RILs to study the relationship between subunits expression quantity and characteristics quality. The results showed that: For single subunit, the expression quantity of 7 is the highest. Then the 2, 5, 12 and 10. The expression of subunit 9 and 1 is the lowest. Subunit N is not expressed. For subunits, the expression quantity of x type and y type are 2+12>5+10>7+9>17+18. The significant relation of 5% only showed between the expression quantity of subunit 10 and protein content. The relationship between expression quantity of others and characteristic quality was not significant. For x type/ytype, 2/12 and 5/10 is negative relation insignificant level. For the subunit(s) in a loci, Only 2+12 effect SDS sedimentation value negative in significant level. 4. With RILs 99G45/Jing 771 and Pm97034/Jing 771, we found that: The effective of Glu-A1, Glu-D3 and Glu-D1 * Glu-D3 for protein content is significant at 5% level. The effect of other loci for protein wre not significant. For SDS sedimentation value, the effect of Glu-D1is the highest, which contribution is 4.2 % .Then the Glu-B1, contribution is 3.3%. The effect of other loci for SDS sedimentationvalue were not significant. In total, for protein content: Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3; for SDS sedimentationvalue: Glu-D1>Glu-B1> Glu-D3>Glu-A1>Glu-B3. The effect of alleles in Glu-D1 and Glu-D3 loci are significant at 1% or 5%. In Glu-A1, 1>N; Glu-B1, 7+9>17+18>14+15; Glu-D, 5+10>2+12; Glu-B3, GB>JB>PB; Glu-D3, GB>JB>PB. For SDS sedimentation, Glu-A1, 1>N; Glu-B1, 7+9=17+18>14+15; Glu-D1, 5+10>2+12; Glu-B3, GB>JB>PB; Glu-D3, GB>JB>PB. The best combinations for SDS sedimentation value is 1,7+9,5+10,GB,GD. 5. Because of the difference of GB and PB for SDS sedimentation value, we selected the specific primer for LMW-GS loci to amplified the Glu-B3 of Jing771, 99G45and Pm97034. We got 3 amplify fragment (Gene Bank accession number are DQ539657-DQ539659). We found that the fragment of Pm97034 were deleted a repetitive 7 amino acid domain, which is perhaps the reason effect the gluten strength. Furthermore, in the position 124 of sequence 99G45, L has been replaced with P. Position 158, T replaced M, which may be the reason why the Glu-B3 locus of 99G45 is prefer to Pm97034 when refer to SDS sedimentation value. 6. Comparing the results of RILs and common wheat, we found that perhaps just the1BL/1RS made the difference of loci in different accession.

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青稞,是我国藏区居民对裸大麦的称谓,它不仅是藏民的主要食粮、燃料和牲畜饲料,而且也是啤酒、医药和保健品生产的原料;青稞不仅为藏区人民的健康和经济发展做出了很大的贡献,而且对人类健康和社会经济的可持续发展都有重要的意义。青藏高原是我国及世界上青稞分布和种植面积最大的地区,资源极其丰富。虽然从经典遗传直到分子标记对我国大麦遗传多样性都有研究,但研究手段、数量仍然不够深入,对我国大麦资源遗传多样性研究的信息非常有限,不能很好地满足大麦遗传研究和育种应用的需要,尤其是对西藏栽培大麦的遗传多样性的研究还只是刚刚开始,关于栽培青稞多态性的研究报道很少。本研究采用SSR标记和蛋白质电泳两类技术,从SSR标记位点、单体醇溶蛋白、B组醇溶蛋白和淀粉粒结合蛋白(SGP)等四个方面对我国青藏高原栽培青稞的遗传多样性进行了综合评价。 SSR标记具有基因组分布广泛、数量丰富、多态性高、容易检测、共显性、结果稳定可靠、实验重现性好、操作简单、经济、易于高通量分析等许多优点,被认为是用于遗传多样性、品种鉴定、物种的系统发育、亲缘关系及起源等研究的非常有效的分子标记。本研究采用SSR标记分析了64份青藏高原栽培青稞的遗传多样性,同时评估SSR标记在我国大麦育种和品种鉴定中的应用潜力。选择了30个已知作图位点SSR标记,其中25个标记与重要性状的控制位点连锁紧密。选择的30个SSR标记,5个未得到很好的扩增产物,3个无多态性。22个多态性SSR标记位点中,每位点检测出等位基因2~15个,共检测出等位基因132个,平均每位点6.0 个。各多态位点检测出基因型为2~11种,位点HVM33的基因型最多。各多态位点的多态信息指数为0.16~0.91, 平均为0.65。根据PIC值选择了13个SSR标记用于我国青藏高原栽培青稞基因型鉴定,这些标记的PIC值为0.6以上。结合PIC值和基因型差异,选择了8个多态信息含量高的SSR标记,构建了高效指纹图谱,此图谱能把64份材料完全区分。 贮藏蛋白电泳分析是研究相关编码蛋白基因多态性的非常有效的方法。大麦单体蛋白与小麦醇溶蛋白相对应,具有丰富的多态性,可用于大麦遗传多样性、品种鉴定和群体进化等研究。本研究通过A-PAGE电泳技术研究了84份青藏高原栽培青稞的单体醇溶蛋白多态性。大麦单体醇溶蛋白图谱与小麦醇溶蛋白电泳图谱类似,所分离的蛋白清晰地分为ω-,γ-,β-和α-四个部分。青藏高原栽培青稞单体醇溶蛋白具有丰富的多态性,84份青稞材料中存在43条不同的蛋白带,75种组合带谱;其中67种为单一材料所独有,另8种则分别包含了2-3份材料。每份材料中拥有醇溶蛋白带为6-16条,含有6-10条单体醇溶蛋白带材料较多。西藏和四川材料群体单体醇溶蛋白多态性不同,具有区域特异性。西藏材料中发现了40条不同蛋白带,3条特异带,46 种蛋白组合;四川材料中出现了40种不同蛋白带,26种条带组合, 3条特异带。基于单体蛋白多态性的聚类与材料的来源有一定的相关性。A-PAGE单体蛋白具有丰富的多态性,可作为遗传研究和品种鉴定的标记。 大麦醇溶蛋白(hordein)是大麦籽粒的主要贮藏蛋白,与大麦的营养品质和加工品质密切相关,而且具有丰富的多态性,广泛用于品种鉴定、种质筛选、遗传多样性和亲缘关系研究。B组醇溶蛋白是主要的醇溶蛋白组份,约占总醇溶蛋白的80%,而且具有丰富的多态性。本研究采用SDS-PAGE分析了72份青藏高原栽培青稞B组醇溶蛋白的遗传多样性。青藏高原栽培青稞B组醇溶蛋白具有丰富的多态性,72份青稞材料中存在15种蛋白带,30种组合带谱,其中15种为单一材料所独有,另15种则分别包含了2-10份材料。每份材料中B组醇溶蛋白条带数为4-8条,含5、6条的材料较常见。不同来源的群体材料间B组醇溶蛋白组成存在差异,西藏青稞含有26种蛋白组合带谱,其中有19种特异带谱;四川群体中共发现11种蛋白组合带型,其中有4种特有带谱。两群体中都存在稀有条带。聚类分析将材料分成三组,材料聚类与材料来源地没有明显的相关性。 淀粉粒蛋白(Starch granule proteins, SGPs)是一类与淀粉粒结合的微量蛋白,一些淀粉粒蛋白具有淀粉生化合成中主要的酶蛋白功能,其变异会影响淀粉含量和特性,从而影响淀粉的应用。关于我国大麦淀粉粒组成研究还未见报道。本实验首次开创了我国大麦淀粉粒结合蛋白的研究工作。采用SDS-PAGE电泳技术研究了青藏高原栽培青稞的SGP组成,并分析了不同SGP组合间淀粉含量的差异,初步探索了所分离的SGP蛋白与淀粉合成的关系。66份青稞材料中分离了10种主要的SGP,其表观分子量为40-100KD,低于60KD的SGP带有7条,共有16种组合带谱;各SGP蛋白和组合带谱出现的频率存在差异,青藏高原青稞的SGP组成存在多态性。西藏青稞和四川青稞的SGP组成有很大差异,SGP组成具有地域差异性,西藏青稞含有12种蛋白组合带谱,其中有9种特异带谱;四川群体中共发现7种蛋白组合带型,其中有4种特有带谱;两群体中仅有3种共同的蛋白组合带谱。SGP蛋白特性将66份青稞分为三组, 即Ⅰ、Ⅱ、Ⅲ,材料聚类与材料来源具有一定的相关性。不同组合带谱材料间淀粉含量差异显著性检验结果显示,不同带谱间材料的总淀粉含量、直链淀粉含量和支链淀粉含量有差异,带谱2(SGP1+3+7+9+10)和8(SGP1+2+4+6+8)的总淀粉含量及支链淀粉含量显著大于组合带谱3(SGP1+3+7+10)的总淀粉含量。组合带谱7(SGP1+2+6+8)的直链淀粉含量显著低于带谱11(SGP1+5+8)的直链淀粉。带谱SGP2、3、4、5、6、7、8、9、10可能参与淀粉合成,SGP9可能与高支链淀粉的合成相关。 SSR标记位点、单体醇溶蛋白、B组醇溶蛋白、淀粉结合蛋白等四个方面的研究结果表明青藏高原SSR标记多态性、单体醇溶蛋白多态性、B组醇溶蛋白多态性和SGP多态性都非常丰富,与青藏高原是栽培青稞的多样性分布中心的观点一致。 青藏高原栽培青稞的SSR标记、单体醇溶蛋白、B组醇溶蛋白和SGP多态性表现出很大差异。SSR标记覆盖了整个基因组,多态性非常高。单体蛋白、B组醇溶蛋白、SGP蛋白是育种中非常关注的性状,他们只是代表基因组中的某一区域或位点,多态性相对较低。但单体蛋白多态性很高,84份材料中检测出43条不同蛋白带,75种不同的组合带谱。SSR标记技术和单体蛋白技术都是遗传多样性研究的有力工具,但单体蛋白技术不仅多态性高,而且经济、操作简便,是种质鉴定的理想方法。 对不同标记的多态性材料数据进行聚类,聚类图能为我们提供各材料间的遗传相似信息,为材料选择提供参考。但材料聚类与材料来源的地理区域的相关性表现不一致。SSR聚类和B组醇溶蛋白聚类与材料的来源地无相关性,而单体醇溶蛋白和SGP聚类与材料来源地有一定相关性,即西藏群体和四川群体分别有集中类群,这可能是人为选择的附加效应。 不同来源的群体材料的遗传多样性不同,具有区域特异稀有基因,加强不同地区间资源的交换和配合使用,有利于增加群体遗传多样性和新品种培育。 青藏高原栽培青稞的麦芽浸提性状、淀粉性状、病虫及裸粒等重要农艺性状控制位点存在丰富的变异,遗传基础宽广,可能蕴藏着多种不同的等位基因,是研究重要性状遗传特性、基因资源挖掘和遗传育种的宝贵资源库。 Hulless barley, due to its favorable attributes such as high feed value, good human nutrition,rich dietary fiber and ease processing, attracts people,s attention . Hulless barley plays a very important role in Tibetan life, used as essential food crop, main animal feed and important fuel. In addition to tsampa (roasted barley flour), a main food for Tibetan, hulless barley is also made into cake, soup, porridge, recent naked barley liquor and cornmeal. Qinghai-Tibet Plateau is one of a few areas which plant naked barley widely in the world and also has a long growing history. Genetic diversity of the cultivated hulless barley in this region , however, has not been documented. The study of genetic diversity existing within this population is of particular interest in germplasm identification, preservation, and new cultivar development. This study analyzed the genetic diversity of the cultivated naked barley from Qinghai-Tibet plateau through the study of SSR marker loci and monomeric prolamins, B-horden and starch granule proteins. SSRs are present abundantly in genomes of higher organisms and have become a popular marker system in plant studies. SSRs offer a number of advantages, such as the high level of polymorphisms, locus specificity, co-dominance, reproducibility, ease of use through PCRand random distribution throughout the genome. In barley, several hundred SSRs have been developed and genetically mapped and can therefore be selected from specific genomic regions. The genetic diversity of 64 cultivated naked barley from Tibet and Sichuan was studied with 30 SSRs of known map location.Among the selected SSR markers, PCR products of 5 SSR markers were not obtained and 3 SSR marker loci were monomeric. A total of 132 alleles were identified at 22 polyomeric SSR loci. The number of alleles per locus ranged from 2 to 15, with an average of 6.0. The polymorphism information content values for the SSRs ranged from 0.08 to 0.94, with an average of 0.65. 13 SSR markers with the PIC value >0.6 have been selected for discrimination of Qinghai-Tibet naked barley genotypews. A finger Print map was developed through 7 SSR markers with the high PIC value. It could be used as an efficient tool for gene discovery and identification of gernplasm. Hordeins, the main storage proteins of the barley seed, are composed of momomeric and polymeric prolamins and divided into -A, B, C and D groups in order of decreasing electrophoretic mobility. Hordeins show high inter-genotypic variation and have been extensively used as markers for cultivar identification and analyzing the genetic diversity. This study analyzed the genetic diversity of B-hordein in 72 naked barley from Qinqhai-Tibet Plateau. Extensive diversity was observed. A total of 15 different bands and 30 distinct patterns were found. Jaccard's coefficient of similarity was calculated, and the accessions were divided into three main groups by cluster analysis using UPGMA. Differentiation among the populations from different collecting regions based on the polymorphism of B-hordein was investigated. Monomeric prolamins show high inter-genotypic variation and have been used as molecular markers for cultivar identification, analyzing the genetic diversity in collections and investigating the evolution processes and structure of populations However, the cultivated hulless accessions from Qinghai-Tibet Pateau in China have never been examined with respect to monomeric prolamins. This study analyzed the genetic diversity of monomeric prolamins (protein fraction corresponding to wheat gliadins) using the Acid -PAGE technique in eighty-four cultivated hulless barley from Qinqhai-Tibet Plateau in China. Extensive diversity was observed. A total of 43 different bands were found, of which 21 different bands were in the region of ω group, 8 in the region of γ, 8 in the region of β, and 6 in the region of α group. Among the 86 accessions, 75 distinct patterns were identified. The number of bands ranged from 6 to 16, depending on the variety. Jaccard’s coefficient of similarity was calculated, and the lines were grouped by cluster analysis using UPGMA. A dendrogram was obtained from the analysis of the groups and five main clusters were identified. No relationship between the distribution in the dendrogram and growth habits and origins of the cultivars could be detected. Starch is the major constituent of the cereal endosperm, comprising approximately 65% of the dry weight of the mature wheat grain. The starch formed in all organs of plants is packaged into starch granules, which vary widely between species and cultivars in size and shape. Wheat endosperm starch granules contain about corresponding to the main biosynthase of starch. This report firstly dealed with intraspecific variation of the major SGPs in cultivated naked barley from Qinghai-Tibet plateau. A total of 10 major SGPs were observed in the range of 40KD-100KD and 16 types of patterns were found. Based on the variation of SGPs, accessions studied were classified into 3 groups. A geographical cline of electrophoregram was observed. In addition, significance test of the difference of starch content among groups and types of patterns were done, and the results indicated those SGPs could be related to the content of starch. Diagram obtained through cluster analysis exhibited a structuration of diversity and genetic relationship among cultivated hulless accessions. In breeding program, parents with genetically distant relationship for hybridization will increase genetic diversity of progenies. In conclusion, cultivated naked barley from Qinghai-Tibet Plateau in China presents a high variability with respect to monomeric prolamins,SSR markers , B- hordeins and SGPs. The result of this study supports Qinghai-Tibet Plateau is the center of cultivated hulless barley and the cultivated naked barley is considered to be a gene pool with large diversity and could be applied to breeding for cereal.

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本文以中国科学院成都生物研究所培育的同源四倍体水稻和二倍体水稻为材料,进行遗传差异及产量、品质性状的研究:1、以二倍体水稻为对照,研究了同源四倍体水稻在2004 年和2005 年的结实情况。结果同源四倍体的花粉育性、结实率均不同程度下降,尤其低代材料更是大幅度下降。F 检验表明,同源四倍体不同个体间的各产量性状均差异显著,说明其具有很大的遗传改良潜力。从1996 年到2005 年对部分同源四倍体水稻进行了连续选择改良,T 检验表明经过9 年的选择改良,其结实率显著提高。本文还对同源四倍体水稻各产量性状间的相关性进行了分析,结果结实率与花粉育性、穗着粒数、穗实粒数极显著相关;理论产量与花粉育性、有效穗数、穗着粒数、穗实粒数、结实率及千粒重极显著相关。i2、用(CT)n 微卫星标记和PCR-Acc Ι分子标记对40 份同源四倍体和14 份二倍体水稻Wx 基因进行研究。结果,(CT)n 微卫星标记检测,Wx 基因呈Wx1、Wx2 和Wx3 3 种多态性;PCR-Acc Ι 检测,Wx 基因表现为G-型和T-型。测定稻米直链淀粉含量(AC)、胶稠度(GC)和糊化温度(GT),并探讨其与Wx 基因的关系,结果,二倍体和同源四倍体水稻均存在:Wx 基因型相同,AC 差异较小,Wx 基因型不同时,AC 差异较大,Wx1 基因型品种AC 最高, Wx2 基因型品种AC 次之,Wx3 基因型品种AC 最低;基因型相同时,同源四倍体AC 低于二倍体;同源四倍体与对应二倍体间,Wx 基因型相同时,AC 差异很小;而Wx 基因型发生变异时,AC 差异很大。同时,进行相关性分析,结果二倍体和四倍体水稻均存在AC、GC 与Wx 基因密切相关;而GT 与Wx 基因相关不显著。综合分析,(CT)n微卫星标记与PCR-Acc Ι 分子标记检测的相关系数为0.842,呈极显著正相关,可以将其结合起来进行同源四倍体新品种的选育和改良。3、利用RAPD 技术,对同源四倍体和二倍体水稻的遗传差异进行分析。17条引物在同源四倍体中扩增出178 条带(PPB=81.5%),在二倍体中扩增出173条带(PPB=76.3%);同源四倍体和二倍体的Shannon 遗传多样性指数分别为0.4848 和0.4679,多态信息量分别为0.3301 和0.3216,遗传距离分别为0.3572和0.3460;同源四倍体与其对应二倍体间遗传距离为0.1914-0.4633,平均为0.2914。表明同源四倍体的遗传多样性高于二倍体,且同源四倍体与其二倍体之间存在较大的遗传差异,这些将为水稻品种改良和新品种选育提供科学依据。上述产量、品质性状及遗传差异分析的结果,不仅有利于加快同源四倍体水稻的遗传改良进程,而且为进一步研究、利用同源四倍体水稻奠定了初步基础。 AbstractStudy on genetic diversity, yield characters and quality traitsof autotetraploid and diploid riceLiu Yuhua (Botany)Directed by Associate Prof. Tu ShengbinIn this study, diploid and autotetraploid rice, which were cultivated in ChengduInstitute of Biology were analyzed in genetic diversity, yield characters and qualitytraits.In the study, 2 diploid and 29 autotetraploid rice(2n=4x=48) materials, including4 preliminary and 25 advanced generation, were investigated for yield characters.Compared with diploid check, the pollen fertility and seed set of autotetraploiddeclined dramatically, especially in preliminary generation. F-test indicated that therewere remarkable differences among different varieties, showing that autotetraploidmaterials had strong potential for improvement. From 1996 to 2005, someautotetraploid rice had been selected and improved. T-test showed that seed setincreased obviously. The relationships among yield characters of autotetraploid ricewere analyzed. Seed set was strongly correlated with pollen fertility, total grainnumber per panicle and productive grain number per panicle; theoretical yield wasstrongly correlated with pollen fertility, productive panicle number per plant, totalgrain number per panicle, productive grain number, seed set and 1000-grain weight.Wx genotypes of 40 autotetraploid rice and 14 diploid rice were tested by usingthe (CT)n microsatellite marker and a cleaved amplified polymorphic sequence(CAPS) molecular marker named PCR-Acc Ι. Three microsatellite alleles wereproduced, i.e. Wx1, Wx2 and Wx3 both in autotetraploid and in diploid rice.Comparatively, PCR- Acc Ι molecular marker produced two genotypes, G-type andT-type for both autotetraploid and diploid rice. In this study, amylose content (AC), gel of consistency (GC) and gelatinization temperature (GT) of rice grain weremeasured and their relationships with Wx alleles were analyzed. The results showedthat variation of AC between autotetraploid and diploid rice was small when they hadthe same Wx genotype. However, variation of AC turned to be large when the Wxgenotypes were different. Actually, AC met the maximum value in Wx1 varieties andWx2 varieties the middle and Wx3 varieties the minimum. And AC was lower inautotetraploid than in diploid. Correlation analysis was done in this experiment. ACand GC of rice grain were probably controlled by Wx gene or other gene whoselocation was strictly linked to Wx gene, while GT of rice was not. The correlationcoefficient between Wx genotypes which revealed by (CT)n microsatellite marker andPCR-Acc Ι molecular marker was 0.842 with significant level. That revealed aconsistent result between the two types of markers. So it was possible to utilize boththe two types of markers to select and promote germplasm of autotetraploid rice.RAPD molecular markers were used to analyze the genetic diversity betweendiploid and autotetraploid rice. 178 repeatable bands were detected through 17 RAPDprimers with percentage of polymorphic bands was 81.5% in autotetraploid rice while173 repeatable bands were detected with percentage of polymorphic bands was 76.3%in diploid rice. According to the measurement of Shannon index, polymorphicinformation content and genetic distance, genetic diversity of autotetraploid was on ahigher level, genetic variation between autotetraploid and diploid rice was relativelyhigh. All these contributed to the genetic selection and improvement in rice breeding.As mentioned above, the results are not only helpful to promote the process ofrice improvement, but also to confirm the basic for further study of autotetraploid rice.

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株高是农作物的重要农艺性状之一,适度矮化有利于农作物的耐肥、抗倒、高产等。20世纪50年代,以日本的赤小麦为矮源的半矮秆小麦的培育和推广,使得世界粮食产量显著增长,被誉为“绿色革命”。迄今为止,已报到的麦类矮秆、半矮秆基因已达70多个,但由于某些矮源极度矮化或者矮化的同时伴随不利的农艺性状,使得真正运用于育种实践的矮源较少。因此,发掘和鉴定新的控制麦类作物株高的基因,开展株高基因定位、克隆及作用机理等方面的研究,对实现麦类作物株高的定向改良,具有重要的理论意义和应用价值。簇毛麦(Dasypyrum villosum,2n=14,VV)是禾本科簇毛麦属一年生二倍体异花授粉植物,为栽培小麦的近缘属。本课题组在不同来源的簇毛麦杂交后代中发现了一株自然突变产生的矮秆突变体。观察分析了该突变体的生物学特性,对矮秆性状进行了遗传分析,对茎节细胞长度、花粉的活力进行了细胞学观察,考察了该突变体内源赤霉素含量及不同浓度外施赤霉素对突变体的作用,分析了赤霉素生物合成途径中的内根贝壳杉烯氧化酶(KO)和赤霉素20氧化酶(GA20ox)的转录水平,对赤霉素20氧化酶和赤霉素3-β羟化酶(GA3ox)进行了克隆和序列分析,并对GA20ox进行了原核表达和表达的组织特异性研究。主要研究结果如下:1. 该突变体与对照植株在苗期无差异,在拔节后期才表现出植株矮小,相对对照植株,节间伸长明显受到抑制,叶鞘长度基本不变。在成熟期,对照植株的平均株高为110cm,而突变株的平均株高为32cm,仅为对照植株的1/3 左右。除了株高变矮以外,在成熟后期,突变株还表现一定程度的早衰和雄性不育。I2-KI染色法观察花粉活力结果表明,对照植株花粉90%以上都是有活力的,而突变植株的花粉仅20%左右有活力。2. 突变株与对照植株的杂交F1代均表现正常株高,表明该突变性状为隐性突变。F1代植株相互授粉得到的168株F2代植株中,株高出现分离,正常株高(株高高于80cm)与矮秆植株(株高矮于40cm)的株数比为130:38,经卡方检验,其分离比符合3:1的分离比,因此推测该突变体属于单基因的隐性突变。3. 用ELISA方法检测突变株和对照植株的幼嫩种子中内源性生物活性赤霉素(GA1+3)含量,结果表明突变株的赤霉素含量为36 ng/ml,而对照植株的赤霉素含量为900 ng/ml。对突变株外施赤霉素,发现矮秆突变株的株高和花粉育性均可得到恢复。这些结果表明该突变株为赤霉素缺陷型突变。4. 用荧光定量PCR方法比较突变株与对照植株中内根贝壳杉烯氧化酶和赤霉素20氧化酶的转录水平,结果表明突变株的KO转录水平比对照植株分别提高了6倍(苗期)和16倍(成熟期),突变株的GA20ox转录水平与对照植株在苗期无明显差异,在成熟期突变株较对照植株则提高了10倍左右。这些结果表明该矮秆突变体与赤霉素的生物合成途径密切相关,而且极有可能在赤霉素的生物合成途径早期就发生了改变。5. 以簇毛麦总基因组为模板,同源克隆了GenBank登录号为EU142950,RT-PCR分离克隆了簇毛麦的GA3ox基因cDNA全长序列,分析结果表明该cDNA全长1206bp,含完整编码区1104bp,推测该序列编码蛋白含368个氨基酸残基,分子量为40.063KD,等电点为6.27。预测的氨基酸序列含有双加氧酶的活性结构,在酶活性中心2个Fe离子结合的氨基酸残基非常保守。该序列与小麦、大麦和水稻的GA3ox基因一致性分别为98%、96%、86%。基因组序列与cDNA序列在外显子部分一致,在478-715bp和879-1019bp处分别含238bp和140bp的内含子。6. 通过RT-PCR技术克隆了簇毛麦的GA20ox基因全长,命名为DvGA20ox,GenBank登录号为EU142949。该基因全长1080个碱基,编码359个氨基酸,具有典型的植物GA20ox基因结构。该基因编码的蛋白质与小麦、大麦、黑麦草等GA20ox蛋白的同源性分别为98%,97% 和91%。该序列重组到原核表达载体pET-32a(+)上,将获得的重组子pET-32a(+)-DvGA20ox转化大肠杆菌BL21pLysS后用IPTG进行诱导表达。SDS-PAGE分析表明,DvGA20ox基因在大肠杆菌中获得了高效表达,融合蛋白分子量为55kDa。定量PCR分析表明,该基因在簇毛麦不同器官中的表达差异明显:叶片中表达水平最高,根部表达水平次之,茎部和穗中表达较弱。在外施赤霉素后,该基因的表达水平在两小时以后急剧下降,表明该基因的表达受自身的反馈调节。本研究结果认为,(1)该簇毛麦矮秆突变体为单基因的隐性突变;(2)该矮秆突变体为赤霉素敏感突变,内源赤霉素含量检测表明突变体的内源性赤霉素含量仅为对照植株的1/30;(3)荧光定量PCR结果表明突变株的赤霉素生物合成途径的关键酶基因表达水平比对照植株高,而且突变植株的赤霉素生物合成改变很可能发生在赤霉素生物合成途径的早期;(4)GA20ox有表达的组织特异性,且受到自身产物的反馈调节。 Plant height is an impotrant agronomic trait of triticeae crops.Semi-dwarf cropcultivars, including those of wheat, maize and rice, have significantly increased grainproduction that has been known as “green revolution”. The new dwarf varieties couldraise the harvest Index at the expense of straw biomass, and, at the sametime, improvelodging resistance and responsiveness to nitrogen fertilizer. Moreover, dwarf traits ofplant are crucial for elucidating mechanisms for plant growth and development aswell. In many plant species, various dwarf mutants have been isolated and theirmodles of inheritance and physiology also have been widely investigated.The causesfor their dwarf phenotypes were found to be associated with plant hormones,especially, gibberellins GAs.Dasypyrum villosum Candargy (syn.Haynaldia villosa) is a cross-pollinating,diploid (2n = 2x = 14) annual species that belongs to the tribe Triticeae. It is native toSouthern Europe and West Asia, especially the Caucasuses, and grows underconditions unfavorable to most cultivated crops. The genome of D. villosum,designated V by Sears, is considered an important donor of genes to wheat for improving powdery mildew resistance, take-all, eyespot, and plant and seed storageprotein content. A spontaneous dwarf mutant was found in D. villosum populations.The biological character and modles of inheritance of this dwarf mutant are studied.The cell length of stem cell is observed. The influence of extraneous gibberellin tothe dwarf mutant is also examined; the transcript level of key enzyme of gibberellinbiosynthesis pathway in mutant and control plants is compared. GA3ox and GA20oxare cloned and its expression pattern is researched.1. The dwarf mutant showed no difference with control plants at seedlingstage.At mature stage, the average height of control plants were 110cm and the dwarfplants were 33cm. The height of the mutant plant was only one third of the normalplants due to the shortened internodes. Cytology observation showed that theelongation of stem epidermal and the parenchyma cells were reduced. The dwarfmutant also shows partly male sterile. Pollen viability test indicates that more than80% of the pollen of the mutant is not viable.2. The inheritance modle of this dwarf mutant is studied. All The F1 plantsshowed normal phenotype indicating that the dwarfism is controlled by recessivealleles. Among the 168 F2 plants, there are 130 normal plants and 30 dwarf plants, thesegregation proportion accord with Mendel’s 3:1 segregation. We therefore proposethat this dwarf phenotype is controlled by a single recessive gene.3. Quantitative analyses of endogenous GA1+3 in the young seeds indicated thatthe content of GA1+3 was 36ng/ml in mutant plants and 900ng/ml in normal plants.The endogenous bioactive GA1+3 in mutant plants are only about 1/30 of that innormal plants. In addition, exogenously supplied GA3 could considerably restore themutant plant to normal phenotype. These results showed that this mutant wasdefective in the GA biosynthesis.4. More than ten enzymes are involved in GA biosynthesis. KO catalyzes thefirst cytochrome P450-mediated step in the gibberellin biosynthetic pathway and themutant of KO lead to a gibberellin-responsive dwarf mutant. GA20ox catalyze therate-limited steps so that their transcript level will influence the endogenous GAbiosynthesis and modifies plant architecture. The relative expression levels of genesencoding KO and GA20ox were quantified by real time PCR to assess whether thechanges in GA content correlated with the expression of GA metabolism genes andwhere the mutant occurred during the GA biosynthesis pathway. In mutant plants,the transcript levels of KO increased about 6-fold and 16-fold at the seedling stage and elongating stage respectively comparing with the normal plants. For theseedlings, there was no notable difference in the expression of GA20ox betweenmutant and normal plants. At the elongating stage, GA20ox transcript increased 10times in mutant plants, suggesting that the GA biosynthesis pathway in mutant plantshad changed from the early steps rather than the late steps.5. A full length cDNA of D. villosum gibberellin 3β-hydroxylase homology(designated as DvGA3ox) was isolated and consisted of 1206bp containing an openreading frame of 1104bp encoding 368 predicted amino acid residues. Identityanalysis showed that the gibberellin 3β-hydroxylase nucleotide sequence shared 98%,96% and 86% homology with that of wheat, barley and rice. The predicted peptidecontained the active-site Fe of known gibberellin 3β-hydroxylase and the regionhomologous to wheat, barley and Arabidopsis. The genomic clone of gibberellin3β-hydroxylase has two introns.6. The full-length cDNA of D. villosum gibberellin 20 oxidase (designated asDvGA20ox) was isolated and consisted of 1080-bp and encoded 359 amino acidresidues with a calculated mol wt of 42.46 KD. Comparative and bio-informaticsanalyses revealed that DvGA20ox had close similarity with GA20ox from otherspecies and contained a conserved LPWKET and NYYPXCQKP regions. Tissueexpression pattern analysis revealed DvGA20ox expressed in all the tissues that wereexamined and the highest expression of DvGA20ox in expanding leaves followed byroots. Heterologous expression of this cDNA clone in Escherichia coli gave a fusionprotein that about 55KD. Transcript levels of DvGA20ox dramatically reduced twohours after application of biologically active GA3, suggesting that the biosynthesis ofthis enzymes might be under feedback control.

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穗发芽(PHS,preharvest sprouting)是影响禾本科作物生产的重要的灾害之一。收获时期如遇潮湿天气容易导致穗发芽发生。发生穗发芽的种子内部水解酶(主要是α-淀粉酶)活性急剧升高,胚乳贮藏物质开始降解,造成作物产量和品质严重降低。因此,选育低穗发芽风险的品种是当前作物育种工作中面临的重要任务。 青稞(Hordeum vulgare ssp. vulgare)主要分布于青藏高原,自古以来就是青藏高原人民的主要粮食。近年来,由于青稞丰富的营养成分和特有的保健品质、在燃料工业中的潜力以及在啤酒酿造工业中的利用前景,在发达国家日趋受到重视,掀起综合研究利用的热潮。我国拥有占全世界2/3 以上的青稞资源,具有发展青稞产业的得天独厚的条件。然而,由于青稞收获期间恰逢青藏高原雨季来临,常有穗发芽灾害发生,使青稞生产损失巨大。目前对青稞穗发芽研究很少,适用于育种的穗发芽抗性材料相对缺乏,不能很好的满足青稞穗发芽抗性育种的需要。本研究以青藏高原青稞为材料,对其穗发芽抗性的评价指标和体系进行构建,同时筛选青稞抗穗发芽品种并对其抗性进行评价,还利用分子生物学手段对青稞穗发芽抗性的分子机理进行了初步探讨。主要研究结果如下: 1. 本试验以来自于我国青藏高原地区的青稞为材料,对休眠性测定的温度范围进行探讨,并对各种穗发芽抗性测定方法的对青稞的适用性进行评测。通过探讨温度对13 个不同基因型的青稞籽粒发芽和休眠性表达的影响,对筛选青稞抗穗发芽资源的温度条件进行探索,并初步分析了其休眠性表达的机理。在10,15,20,25,30℃的黑暗条件下,选用新收获的13 个青稞品种为材料进行籽粒发芽实验,以发芽指数(GI)评价其休眠性。结果发现,不同品种对温度敏感性不同,其中温度不敏感品种,在各温度条件下均表现很低的休眠性;而温度敏感品种,其休眠性表达受低温抑制,受高温诱导。15℃至25℃是进行青稞休眠性鉴定的较适宜的温度范围。通过对供试材料发芽后的α-淀粉酶活性,发现温度对青稞种子的休眠性表达的影响至少在一定程度上表现在对α-淀粉酶活性的调控上。随后,对分别在马尔康和成都进行种植的34 份青稞穗发芽指数(SI),穗发芽率(SR),籽粒发芽指数(GI)和α-淀粉酶活性(AA)进行了测定和分析,发现它们均受基因型×栽培地点的极显著影响,且四个参数之间具有一定相关性。GI 参数由于其变异系数较低,在不同栽培地点稳定性好,且操作简便,是较可靠和理想的穗发芽评价参数。SI 参数可作为辅助,区别籽粒休眠性相似的材料(基因型)或全面评价材料(基因型)的穗发芽抗性特征。AA 参数稳定性较差,并且检测方法复杂,因此不建议在育种及大量材料筛选和评价时使用。此外,青稞穗发芽抗性受环境影响较大,评价时应考虑到尽可能多的抗性影响因素及其在不同栽培条件下的变异。 2. 对来自青藏高原的青稞穗发芽抗性特征及其与其它农艺性状间的关系进行研究。通过测定穗发芽指数(SI)、籽粒发芽指数(GI)和α-淀粉酶活性(AA),表明113 份青稞材料的穗发芽抗性具有显著差异。SI、GI 和AA 参数的变幅分别为1.00~8.86、0.01~0.97 和0.00~2.76,其均值分别为4.72、0.63 和1.22。根据SI 参数,六个基因型,包括‘XQ9-5’,‘XQ33-9’,‘XQ37-5’,‘XQ42-9’,‘XQ45-7’和‘JCL’被鉴定为抗性品种。综合SI、GI 和AA 参数,可以发现青稞的穗发芽抗性机制包含颖壳等穗部结构的抗性和种子自身的抗性(即种子休眠性),且供试材料中未发现较强的胚休眠品种,除‘XQ45-7’外,所有品种在发芽第四天均能检测出α-淀粉酶活性。穗部结构和种子休眠的抗性机制因基因型不同而不同,在穗发芽抗性中可单独作用或共同作用。农家品种和西藏群体分别比栽培品种和四川群体的穗发芽抗性强,而在不同籽粒颜色的青稞中未发现明显差异。相关性检验发现,青稞的穗发芽抗性,主要是种子休眠性,与百粒重、开花期、成熟期、穗长、芒长和剑叶长呈显著负相关关系,与株高相关性不显著。农艺性状可以作为穗发芽抗性材料选育中的辅助指标。本试验为青稞穗发芽抗性育种研究提供了必要的理论基础和可供使用的亲本材料。 3. α-淀粉酶是由多基因家族编码的蛋白质,在植物种子萌发时高度表达,与植物种子的萌发能力密切相关。在大麦种子发芽时,高等电点α-淀粉酶的活性远大于低等电点的α-淀粉酶。为了研究不同穗发芽抗性青稞品种中编码高等电点α-淀粉酶Amy1 基因结构与抗性间的关系,我们以筛选得到的抗性品种‘XQ32-5’(TR1)、‘XQ37-5’(TR2)、‘XQ45-7’(TR3),易感品种‘97-15’(TS1)、‘9657’(TS2)以及强休眠大麦品种‘SAMSON’(SAM)为材料,对其Amy1 基因的编码区序列进行克隆和结构分析,并对它们推导的氨基酸序列进行比较。结果显示,青稞Amy1 基因具有三个外显子、两个内含子,编码区中有13 个核苷酸变异位点,均位于2、3 号外显子,2 个变异位点位于2 号外显子。SAM 和TS1 分别在2 号外显子相应位置有5 个相同的碱基(GAACT)的插入片段。相应α-淀粉酶氨基酸序列推导发现,所有核苷酸变异中有8 个导致相应氨基酸残基的改变,其余位点为同义突变。青稞Amy1 基因编码区序列品种间相似度高达99%以上,部分序列变异可能与其穗发芽抗性有关。随后,我们又通过SYBR Green 荧光定量技术对该基因在不同发芽时间(1d~7d)的相对表达水平进行了差异性检测。结果发现,7 天内不能检测到SAM 的Amy1 基因表达,5 个青稞品种间的Amy1 基因的相对表达量均随着发芽时间延长而上升,但上升方式有所不同。弱抗品种该基因表达更早,转录本增加速率更大,且在4~5 天可达到平台期。发芽7 天中,抗性品种总转录水平明显低于易感品种。本研究结果表明,青稞Amy1 基因的转录水平是与其穗发芽抗性高度相关。 我国青藏高原青稞,尤其是农家品种的穗发芽抗性具有丰富的变异,蕴藏着穗发芽抗性育种的宝贵资源。本研究为青稞穗发芽抗性育种建立了合理抗性评价体系,筛选出可供育种使用的特殊材料,阐明了农艺性状可辅助穗发芽抗性育种,同时还对穗发芽抗性与α-淀粉酶基因的结构和表达关系进行分析,为青稞穗发芽抗性资源筛选奠定了基础。 Preharvest sprouting (PHS) is a serious problem in crop production. It often takes place when encountering damp, cold conditions at harvest time and results in the decrease of grain quality and great loss of yield by triggering the synthesis of endosperm degrading enzymes (mostly the α-amylase). Therefore, PHS is regarded as an important criterion for crop breeding. In order to minimize the risk of PHS, resistant genotypes are highly required. Hulless barley (Hordeum vulgare ssp. vulgare) is the staple food crop in Qinghai-Tibetan Plateau from of old, where is one of the origin and genetic diversity centers of hulless barley. Recently, interest in hulless barley has been sparked throughout the world due to the demonstrations of its great potential in health food industry and fuel alcohol production. Indeed, hulless barley can also be utilized to produce good quality malt if the appropriate malting conditions are used. In China, overcast and rainy conditions often occur at maturity of hulless barley and cause an adverse on its production and application. PHS resistant genotypes, therefore, are highly required for the hulless barley breeding programs. However, few investigations have been made so far on this issue. The objectives of this study were: 1) to assessment of methods used in testing preharvest sprouting resistance in hulless barley; 2) to evaluate the variability and characteristics of PHS resistance of hulless barley from Qinghai-Tibet Plateau in China; 3) to select potential parents for PHS resistance breeding; 4) to primarily study on the molecular mechanism of PHS resistance of hulless barley. Our results are as followed: 1. We investigated the temperature effects on seed germination and seed dormancy expression of hulless barley, discussed appropriate temperature range for screening of PHS resistant varieties, and analyzed the mechanism of seed dormancy expression of hulless barley. The dormancy level of 13 hulless barley were evaluated by GI (germination index) values calculating by seed germination tests at temperature of 10,15,20,25,30℃ in darkness. There were great differences in temperature sensitivity among these accessions. The insensitive accessions showed low dormancy at any temperature while the dormancy expression of sensitive accessions could be restrained by low temperature and induced by high temperature. The temperature range of 15℃ to 25℃ was workable for estimating of dormancy level of hulless barley according to our data. Analysis of α-amylase activity showed that the temperature effects on seed germination and the expression of seed dormancy be achieved probable via regulating of α-amylase activity. Furthermore, we evaluated the differences in sprouting index (SI), sprouting rate (SR), germination index (GI) and α-amylase activity (AA) between Maerkang and Chengdu among 34 accessions of hulless barley from Qinghai-Tibetan Plateau in China. These PHS sprouting parameters were significantly affected by accession×location, and they had correlation between each other. GI was the most reliable parameter because of its low CV value, good repeatability and simple operation. SI could assist in differentiating between accessions of similar dormancy or overall evaluation of the resistance. AA was bad in repeatability and had relatively complex testing method, therefore, not appropriate for breeding and evaluation and screening of PHS resistant materials. Besides, since PHS resistance of hulless barley was greatly influenced by its growth environment, possibly much influencing factors and variations between cultivated conditions should be considered. 2. In this study, large variation was found among 113 genotypes of hulless barley (Hordeum vulgare ssp.vulgare) from Qinghai-Tibetan Plateau in China, based on the sprouting index (SI), germination index (GI) and α-amylase activity (AA) which derived from sprouting test of intact spikes, germination test of threshed seeds and determination of α-amylase activity, respectively. The range of SI, GI and AA was 1.00~8.86, 0.01~0.97 and 0.00~2.76,the mean was 4.72, 0.63 and 1.22 espectively. Six resistant genotypes, including ‘XQ9-5’, ‘XQ33-9’, ‘XQ37-5’, ‘XQ42-9’, ‘XQ45-7’ and ‘JCL’, were identified based on SI. Integrating the three parameters, it was clear that both hulls and seeds involved in PHS resistance in intact spikes of hulless barley and there was no long-existent embryo dormancy found among the test genotypes. All the genotypes, except ‘XQ45-7’, had detectable α-amylase activity on the 4th day after germination. There was PHS resistance imposed by the hull and seed per se and the two factors can act together or independent of each other. Besides, landraces or Tibet hulless barley had a wider variation and relatively more PHS resistance when compared with cultivars or Sichuan hulless barley. No significant difference was found among hulless barley of different seed colors. The correlation analysis showed PHS resistance was negatively related to hundred grain weight, days to flowering, days to maturity, spike length, awn length and flag length but not related to plant height. This study provides essential information and several donor parents for breeding of resistance to PHS. 3. Alpha-amylase isozymes are encoded by a family of multigenes. They highly express in germinating seeds and is closely related to seed germination ability. In barley germinating seeds, the activity of high pI α-amylase is much higher than low pI α-amylase. The aim of this study was to determine the relationship between preharvest sprouting resistance of hulless barley and the gene structure of Amy1 gene which encodes high pI α-amylase. The coding region and cDNA of Amy1 gene of three resistant accessions, including ‘XQ32-5’ (TR1), ‘XQ37-5’ (TR2), ‘XQ45-7’ (TR3), two susceptible accessions ‘97-15’ (TS1), ‘9657’ (TS2) and one highly dormant barley accession ‘SAMSON’ (SAM) was cloned. Analysis of their DNA sequences revealed there were three exons and two introns in Amy1 gene. Thirteen variable sites were in exon2 and exon3, 2 variable sites were in intron2. SAM and TS1 had a GAACT insert segment in the same site in intron2. Only 8 variable sites caused the change of amino acid residues. There were 99% of similarity between the tested hulless barley and some of the variable sites might be related with preharvest sprouting resistance. Then, we investigated the expression level of Amy1 gene in the 7-day germination test. Results of quantitative real-time PCR indicated that the relative expression trends of Amy1 gene were the same but had significant differences in the increase fashion between hulless barleys and no detectable expression was found in SAM. Susceptible accessions had earlier expression and faster increase and reached the maximum on day 4 ~ day 5. Besides, total transcripts level was found lower in resistant accessions than susceptible accessions. This study indicated that α-amylase activity was highly related to the transcription level of Amy1 gene which not correlated to missense mutation sites. In conclusion, hulless barley, especially the landraces from Qinghai-Tibetan Plateau in China possesses high degree of variation in PHS performance, which indicates the potential of Tibetan hulless barley as a good source for breeding of resistance to PHS. This study provides several donor parents for breeding of resistance to PHS. Our results also demonstrate that agronomic traits may be used as assistants for PHS resistance selection in hulless barley. Besides, analysis of high pI α-amylase coding gene Amy1 revealed the relative high expression of was Amy1 one of the mainly reason of different PHS resistance level in hulless barley.

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课题组在不断地创制新的同源四倍体材料的同时,连续多年以提高结实率为目的培育、筛选自交系材料,已获得自交繁殖十二年的高代自交系材料。相对于诱导创制初期,材料表现出的结实率低,同种系单株间的差异较大;高代材料已表现出较显著的结实率提升和较一致的农艺性状表型。 本实验选取课题组多年培育的同源四倍体水稻高代自交系材料,通过形态学、农艺性状和细胞遗传学比较,研究水稻同源四倍体与二倍体之间的异同。结果显示,所有同源四倍体材料的染色体组成均为2N=4X=48,花粉母细胞(PMC)减数分裂行为较正常,99%以上的染色体都能在减数分裂中期I(MI)发生联会、配对,形成四价体和二价体,这与理论染色体组构成相符。在减数分裂过程中,结实率较高的材料染色体异常现象较少而结实率较低的材料染色体异常现象较严重。统计分析表明,二价体和四价体的比例对结实率没有显著影响,但是三价体的数目对结实率有一定影响。这一结果表明了结实率和细胞减数分裂行为可能存在相关性,同源四倍体的减数分裂行为为筛选高结实率的同源四倍体种系提供了依据。 然后,对同源四倍体水稻高代自交系材料进行农艺性状和品质性状的统计与分析。主要针对结实率、每穗实粒数、有效分蘖和穗长等主要农艺性状,以及直链淀粉含量这一重要的品质性状进行统计。将统计结果与1996年诱导加倍的初代材料的数据相对比分析,结果显示所有材料经过多代选育培养,其农艺性状已经有了较显著的提高,同时同源四倍体材料的农艺性状稳定性也有了较显著的提升。如结实率的提高幅度较大,所有材料的平均结实率均显著高于加倍初代,而同种材料不同单株间的结实率差异也显著地减少,变异系数(CV)的平均值由1996年的41.15%减少到了2008年的28.81%。其他重要农艺性状也有不同程度的改良,种内变异系数也相应地降低。此外,实验测量了同源四倍体材料和来源二倍体材料的直链淀粉含量。分析结果显示,部分材料的直链淀粉含量与二倍体亲本产生了较显著的差异,这可能是诱导加倍过程中的遗传变异造成的;同源四倍体材料的种内变异系数(CV)平均值由1996年的6%下降到了2008年的3.88%,显示出在品质性状方面,同源四倍体材料的遗传稳定性也有较显著的增加。同源四倍体材料农艺性状经过多年的选育,表现出一定的提升,同时,经过多年自交纯化,所有材料种系内的性状差异逐渐缩小,说明同源四倍体水稻的遗传稳定性随着自交纯化而增强,这为同源四倍体水稻的进一步选育打下了良好的基础。 最后,通过测量连续两年的自交系材料的遗传多态性,分析材料间遗传差异和种群遗传结构,深入研究连续两代材料间的遗传差异,研究同源四倍体水稻与二倍体材料遗传稳定性之间的差异。实验采用18对SSR微卫星标记对连续两代15个材料,共94份样本进行差异分析。通过扩增条带长度多态性分析,计算不同材料以及同种材料不同世代间的遗传距离,构建同源四倍体和二倍体水稻的分子指纹库,并绘制聚类图。结果显示,同源四倍体和二倍体不同材料间的遗传差异比较大,遗传距离处于0.4757至0.2816之间;而相同品种不同世代材料间的遗传差异较小,但也表现出一定的遗传差异。同种同源四倍体材料不同世代间的遗传差异比二倍体材料更大,两代四倍体材料间遗传距离处于0.1359至0.0485之间;而两代二倍体材料间的遗传距离处于均小于0.0388。结果表明,同源四倍体水稻高代材料具有一定的遗传稳定性,但与来源二倍体材料相比,其世代间的遗传变异性仍然较强。这种结果说明,经过多代的自交纯化培育,同源四倍体水稻材料能够建立起相对稳定的遗传结构,同时,其强于二倍体亲本的变异性有能够为新品种的选育,农艺性状、品质性状的改良提供一定的遗传基础。此外,分析结果表明通过分子标记辅助检验,水稻材料间的遗传多态性能够有效地区分不同的品种,这为水稻品种的分子鉴定提供了一定的依据。 本研究从细胞学鉴定,农艺性状统计分析以及分子标记辅助聚类分析多方面地对同源四倍体水稻高代系进行了研究,对探究同源四倍体水稻的遗传规律,进一步揭示其遗传特性、农艺性状的遗传构成,为进一步选育优质的多倍体水稻提供了一定的理论依据。 This group insists on creating new Autotetraploid Rice (Oryza sativa L.) materials, while improving the seed-setting of them for many years, cultivated and selected the inbred line materials, has obtained the high generation inbred lines after twelve years cultivation. Compared to the early induced materials, which shown the low seed setting, and the large difference between the different plants in the same germ-line; the high generation materials have shown significant improvement in seed setting and more uniform phenotype agronomic traits. The autotetraploid rice high generation inbred lines material, which has been cultivated for more than 12 years, was chose in this experiment. The similarities and differences between autotetraploid and diploid rice was studied through morphological, agronomic and cytogenetic ways. The results showed that all the chromosome of autotetraploid materials are composed of 2N=4X=48, the pollen mother cells (PMC) meiosis behavior is normal, more than 99% chromosomes in metaphase I(MI) were federated and paired to form tetravalents or bivalents, which constitutes a consistent theory of genome. In the meiosis process, the material with a higher seed setting showed less chromosome abnormal than the material whose seed setting is lower. However, statistical analysis showed that the bivalent and tetravalent rate had no significant impact on seed setting, but the number of trivalent had a certain impact on seed setting. The result shows that the seed setting may be related to the meiosis behavior, which provides a basis to cultivate new autotetraploid germ line with high seed setting through the meiotic behavior. Furthermore, the agronomic and quality traits of autotetraploid rice high generation inbred material were statistically analyzed. The statistically analysis was focused on major agronomic traits such as: seed setting, grains per panicle, effective tillers and panicle length, as well as the important quality trait amylose content. The statistic data was compared with the data in 1996, when the first induced generation of autotetraploid material, and the result shows that after a multi-generation breeding, the agronomic traits has been significantly improved in all the materials, while the stability of agronomic traits also significant upgraded. For instant, the seed setting increased significantly, the average seed setting of all materials was significantly higher than the first induced generation, and the differences between different plants in the same species also significantly reduced, the average of the coefficient of variation (CV) was reduced from 41.15% in 1996 to 28.81% in 2008. Other important agronomic traits had improved in different degrees; the coefficient of variation within species is also reduced accordingly. In addition, the amylose content of autotetraploid and diploid materials was measured in this experiment. The results shows that the amylose content of some of the material differed from diploid parents significantly, it may caused by the genetic change during the inducing, autotetraploid materials intra-specific coefficient of variation (CV) average reduced from 6% in 1996 to 3.88% in 2008, shows that this is a significant increase of quality traits stability in autotetraploid rice. Agronomic traits of autotetraploid material shows some improvement after years of breeding, at the same time, after years of purification, all material within the germ-line gradually narrow the differences in traits indicates that autotetraploid rice genetic stability was enhanced, which laid a good foundation for the further autotetraploid rice breeding. Finally, this experiment studied the genetic differences between materials of two generations and researched the difference of genetic stability between diploid and autotetraploid rice materials through investigating the genetic polymorphism, genetic differences between materials and population genetic structure of inbred line materials of two consecutive years.18 pairs of SSR microsatellite markers for 15 materials of two generations were used in this experiment, and the total of 94 samples were analyzed. Through the amplification length polymorphism analysis of different materials and materials in different generations, the genetic distance between materials and generations was analyzed, a diploid and autotetraploid rice molecular fingerprint database and map rendering cluster were constructed. The result shows that the genetic distance is between 0.4757 to 0.2816 among different autotetraploid and diploid materials; the genetic distance between different generations of same species was less, but also shows a certain degree of genetic differences. The inter-generational genetic differences of autotetraploid materials were greater than of the diploid materials, which are 0.1359 to 0.0485 as the genetic distance; comparing with the 0.0388 of diploid materials. The result shows that high generation inbred autotetraploid rice material has a certain genetic stability, but the genetic variation between generations is still strong comparing with the source diploid materials. It indicates that, after many generations of purification cultivation, autotetraploid rice materials established a relatively stable genetic structure, at the same time, stronger variability than its diploid parents are useful in the breeding of new varieties, provides a genetic foundation to the agronomic and quality traits improvement. In addition, the analysis result shows that the through the molecular marker-assisted testing, rice genetic polymorphism between materials can effectively distinguish different species, provides a certain basis for molecular identification of varieties of rice. A series of investigation such as cytological identification, statistical analysis of agronomic traits, molecular marker-assisted cluster analysis was applied in this experiment to research genetic pattern of autotetraploid rice high generation inbred lines, revealed the genetic characteristics and the genetic composition of agronomic traits, provides a theoretical basis for the further selection of high quality autotetraploid rice.

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本文主要研究了具有己酸乙酯酯化活性的真菌菌株的筛选和发酵条件优化。从大曲和糟醅样品中分离纯化获得79株产生透明圈的丝状真菌,菌落形态初步识别结果显示分离菌株包括红曲霉属、根霉属及曲霉属等菌株。其中菌株EM-56酯化酶活力最强,发酵获得的粗酶制剂酶活为172.36 u。根据显微形态、菌落形态及生理生化特征,初步鉴定该菌株为曲霉科红曲霉属紫色红曲霉(Monascus purpureus)。 在此基础上重点研究了菌株EM-56在不同培养基成分及不同培养条件下的产酶情况,确定了最佳培养基和培养条件。通过单因素实验确定在基础培养基中添加最佳碳源为葡萄糖,最佳氮源为蛋白胨。正交优化实验结果确定了最佳培养基组成:以麸皮为基础培养基,添加葡萄糖 2%,蛋白胨 0.3 %,KH2PO4.3H2O 0.05 %,MgSO4.7H2O 0.06 %。菌株EM-56在上述培养基中的最佳发酵条件为:初始pH 5.5,发酵温度为35°C,发酵时间7d,种龄48h,接种量8%,装瓶量50g / 瓶(500mL)。在最佳培养基和发酵条件下,菌株EM-56发酵获得的粗酶制剂酶活达到241.56 u,比优化前提高了40.15%。 In this paper, the research focuses on the selection of fungus with esterifying activity and optimization of fermentation conditions. We isolated 79 strains which had transparent zones from Daqu and fermented grains. The isolated strains contained Monascus、Rhizopus and Aspergillus through primary morphology analysis. The strain of EM-56 which produces strongest esterase was selected. The enzyme activity reached 172.36u. According to related literature, EM-56 was identified as Monascus purpureus through morphology analysis and biochemical determination. We also studied the effects of different medium and fermentation conditions on the esterase production of strain EM-56. The optimal medium and fermentation conditions were determined. Single factor experiment result shows that the optimal carbon source added is glucose and the optimal nitrogen source added is peptone. The optimal fermentation medium determined by orthogonal optimization test is as follows: wheat bran as substrate, glucose 2%, peptone 0.3%, KH2PO4.3H2O 0.05%,MgSO4.7H2O 0.06%. The optimal fermentation conditions are: initial pH 5.5, cultural temperature 35°C, cultural time 7d, seed age 48h, inoculation 8%, medium mass 50g / flask(500mL). The esterse activity of EM-56 cultivated in the optimal medium and fermentation conditions reached 241.56u and increased by 40.15% compared with the original activity.

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猪场废水COD浓度高、氨氮浓度高、悬浮物浓度高,已成为农村面源污染的主要来源,并严重威胁到农村饮用水安全。猪场废水氨氮浓度高、处理难度大,如何采用经济高效的方法,去除氨氮使其达到排放标准,一直是猪场废水处理中面临的重要难题。 厌氧氨氧化是近年受到国内外水处理研究者广泛关注的新型生物脱氮技术,具有不需要外加有机碳源、节省供氧量、降低能耗等优点。虽然国内外研究者对厌氧氨氧化过程的脱氮机理、厌氧氨氧化菌的生理生化特性等进行了多方面的研究,但已有的报道大多以模拟废水为研究对象,以猪场废水为研究对象的报道,在国内外文献中极少有报导。 本论文以猪场废水为主要研究对象,考察了猪场废水的亚硝化过程、厌氧氨氧化的启动过程,并对亚硝化和厌氧氨氧化联合用于猪场废水脱氮进行了探索。 1.论文首先研究了猪场废水的亚硝化过程,考察了废水水质和主要运行条件对亚硝化过程的影响。实验表明:(1)亚硝化阶段反应时间为8到10h时,出水中氨氮和亚硝酸盐浓度比可达到1:1~1:1.23,满足厌氧氨氧化反应对二者比例的要求;达到前述要求时,氨氮去除率达到58.3~65.6 %,亚硝化率在整个过程均保持在97 %以上,COD去除率在59.2~68.6 %;(2)曝气量(溶解氧)对亚硝化过程影响显著,随着曝气量增大,达到厌氧氨氧化要求的氨氮与亚硝酸盐氮浓度比例所需水力停留时间τ越短,pH出现明显下降的时间越短;(3)τ对应的pH在7.8~8.1之间,无需进行pH调节即可满足厌氧氨氧化反应对pH的要求;(4)氨氮和COD降解过程遵循一级反应动力学,氨氮和COD降解的速率常数分别为0.0656~0.0724 1/h和0.0491~0.0664 1/h。 2.在进行亚硝化过程研究的同时,以模拟废水为试验对象,进行厌氧氨氧化启动研究。以反硝化污泥和养殖厂储水池厌氧底泥的混合污泥作为接种污泥,历时大约100天,培育出具有厌氧氨氧化活性的污泥,氨氮和亚硝酸盐氮最高进水浓度分别为223.8 mg/L和171.4 mg/L,去除率最高分别达48%和41.5%,此时二者消耗比例为1.33:1。 3.在猪场废水的亚硝化研究完成和厌氧氨氧化过程初步启动成功后,在模拟废水中逐步加入猪场废水的亚硝化处理出水,逐步实现亚硝化和厌氧氨氧化的组合。亚硝化出水添加到厌氧反应器后,厌氧氨氧化反应仍可继续进行,且去除效率逐步提高。研究发现添加的亚硝化出水中携带的亚硝化细菌在厌氧氨氧化菌膜外层生长并累积,增加了厌氧氨氧化反应基质的传质阻力,妨碍了厌氧氨氧化效率的提高。 4.亚硝化-厌氧氨氧化实际工程应用探索中,生物接触氧化池可在有效去除废水中的有机物的同时实现亚硝化,出水中氨氮和亚硝酸盐比例平均为1.10,可满足后续厌氧氨氧化的要求;在适宜的进水浓度和温度下,ABR池出现了厌氧氨氧化启动的迹象;研究同时发现,水质的波动和气温的变化是工程中影响厌氧氨氧化菌活性的重要因素。 论文的主要创新点在于:(1)以猪场废水为研究对象,以实现厌氧氨氧化为目标,对亚硝化过程进行了比较详细的考察,获得了亚硝化出水满足厌氧氨氧化要求的工艺条件,通过对其COD和氨氮降解过程的考察,得出亚硝化阶段COD降解和氨氮去除的动力学模型;(2)对亚硝化-厌氧氨氧化处理猪场废水进行了探索,确立了影响其污染物去除率稳定的重要因素。 论文的上述研究成果,为厌氧氨氧化技术的实用性研究提供理论依据。 Piggery wastewater, which is characterized by high concentration of COD、ammonium and suspend substance, has become a most important source of non-point source pollution and also severely threats drinking water security in rural area. How to discharge piggery wastewater with the ammonium concentration meeting standard by economical and effective method? This is the most urgent problem in piggery wastewater treatment. As a new biological nitrogen removal technology, Anammox process has been paid more and more attention by researchers all over the world. Anammox has advantages of no need of organic carbon addition, low oxygen consumption and energy consumption. Plenty of investigations have been carried out to the mechanism, physiological and biochemical characteristic of bacteria about Anammox. Most of researches focused on synthetic wastewater, there is rare report about its application in piggery wastewater. In this paper,experimental studies were performed to investigate Sharon process in treatment of piggery wastewater,the start up process of Annammox using synthetic wastewater were studied, the feasibility of applying Sharon-Anammox process in the nitrogen removal of piggery wastewater was evaluated. 1. Sharon process of piggery wastewater was firstly investigated to analyze the effects of water quality and main running parameters, which meet the NH4+-N to NO2--N ratio requirement of successive Anammox. Results showed: (1)During Sharon Process,after 8~10 hours’ reaction the NH4+-N to NO2--N ratio in effluent reached 1:1.0~1:1.23, when the removal percentage of NH4+-N was 58.3~65.6 %, a semi-nitration rate of above 97 % was achieved during the process; meanwhile 59.2~68.6 % of the COD was also removed. (2)The aeration rate(oxygen) had obvious effect on the hydraulic retention time(τ) which met the NH4+-N to NO2--N ratio requirement of Anammox. As aeration rate increased, the hydraulic retention time(τ) was shortened. (3) The pH corresponding to τ was between 7.8 and 8.1, thus it needed no artificial adjustment. (4) The reduction of ammonia and COD followed the first-order reaction kinetics. The velocity constants of ammonia and COD were 0.0656~0.0724 1/h and 0.0491~0.0664 1/h, respectively. 2. The startup of Anammox process using the artificial wastewater was performed simultaneously with Sharon. The aim was to investigate the running parameters of Anammox and make foundation for the combination stage. By using the mixture of denitrifying sludge and anaerobic sludge in tank of the breeding factory, sludge of Anammox activity was cultivated in UASB after 100 days. The removal percentage of NH4+-N and NO2-N were up to 48% and 41.5%, respectively, when the NH4+-N and NO2-N influent concentration were 223.8 mg/L and 171.4 mg/L, respectively, the NH4+-N and NO2-N removal rate was 1.33:1. 3. After investigation of Sharon and startup of Anammox, effluent of Sharon process was added into the synthetic wastewater to combine Sharon and Anammox step by step. It took some time after the addition of Sharon effluent that Anammox reaction continued and the removal rate kept increasing. It indicated that nitrifying bacteria were carried by the Sharon effluent cumulated in the outer layer of Anammox. This enhanced transfer resistance of Anammox reaction and the increasing removal rate was restrained. 4. In the bio-contact oxidation pond of practical project, Sharon process were carried out successfully and organic compounds were removed effectively. An average NO2-N/ NH4+-N rate of 1:1.0 was achieved in the effluent, which met the requirement of successive Anammox. Under condition of suitable influent concentration and temperature, there was evidence that Anammox could start up in ABR. The variety of wastewater and temperature had great affects on Anammox activity in practical engineering. Innovation of this paper: (1) The Sharon process for treating piggery wastewater was discussed in details. Technological parameters that met requirement of Anammox were obtained. The dynamic models of COD and ammonium removal in the process were educed. (2) Sharon-Ananmmox for treatment of piggery wastewater was investigated, and the primary influencing factors was studied. This paper could be a theoretical consult for research of Anammox utility.

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本文从成都龙泉垃圾填埋场和宜宾造纸厂分离到耐酸性能优良的高温产甲烷菌RY3和中温产甲烷菌SH4,并将其与实验室现有的利用不同底物的产甲烷菌配伍组合成了复合菌剂。采用活性污泥作为固体附着物,研制出了固体产甲烷菌复合菌剂。 菌株RY3的pH耐受范围为5.5~10.5,最适生长pH 6.0~8.0。菌株RY3为革兰氏阳性,长杆状,多数单生,不运动;菌落浅黄色,形状近圆形;利用H2+CO2或甲酸盐作为唯一碳源生长,不利用乙酸盐,对氯霉素非常敏感。该菌最适生长温度为55℃~65℃,最适NaCl浓度为0~2%。根据形态和生理生化特性及16S rDNA序列分析将其初步定为热自养甲烷热杆菌(Methanothermobacter thermautotrophicus)。添加RY3菌液与仅添加厌氧污泥作为接种物相比一周内可使达到最大产甲烷速率所需时间缩短三分之二,甲烷总产量提高约1.8倍。菌株SH4的生长pH范围5.5~9.5,其对酸碱具有良好的适应性,培养3天后,在初始pH值为6.0~8.0的培养基中甲烷产量相差不大,且基本达到最大产量。SH4革兰氏染色阳性,短杆状,多数单生,不运动;菌落近圆形,微黄;利用H2+CO2或甲酸盐作为唯一碳源生长,不利用乙酸盐,对氯霉素非常敏感。SH4最适生长pH 为7.0,最适生长温度为35℃,最适NaCl浓度为0~1.5%。实验表明,添加SH4菌液与仅添加厌氧污泥作为接种物相比可使产甲烷启动时间缩短三分之一,甲烷总产量亦有大幅提高。从形态和生理生化特征以及16S rDNA序列分析表明SH4为嗜树木甲烷短杆菌(Methanobrevibacter arboriphilus)。 以活性污泥为附着物,与培养基和菌种经搅拌后厌氧发酵可得产甲烷菌固体复合菌剂。固体复合菌剂的pH耐受范围为5.5~9.5,温度耐受范围为15℃~65℃,表明其对环境的适应性较强。以猪粪为底物进行厌氧发酵,接种复合菌剂进行试验,以接种实验室长期富集的产甲烷厌氧污泥作为对照,在20℃时,发酵甲烷浓度与对照基本一致,但每日产气量优于对照,第15天时接种复合菌剂的发酵瓶每日产气量是对照的1.59倍;50℃时达到最大甲烷含量所需时间比对照缩短三分之二,三周内总产气量约为对照的2.7倍,甲烷总产量约为2.8倍。以不加接种物为对照,接种复合菌剂20℃时发酵甲烷含量达到50%约需2周,对照2周内甲烷含量最高仅为4.3%;50℃时接种复合菌剂发酵仅需约1周甲烷含量便可达50%,对照则至少需要2周。 In this paper, high-temperature Methanogen RY3 and middle-temperature SH4 were isolated from Chengdu Longquan refuse landfill and Yibin paper mill. They could be used to make compound inoculum that producing methane with the existing Methanogens utilized different substrate. With using anaerobic activated sludge be solid fixture, the process had been designed to produce solid compound inoculum. Strain RY3 possessed excellent capacity of acid and alkali-tolerant. The pH-tolerant scale of RY3 was 5.5~10.5 and its optimum pH value for growth was 6.0~8.0. RY3 was G+, long-rod shape, monothetic and nonmotile, the colony was pale yellow with suborbicular-shape. Formate or H2+CO2 but not acetate was utilized by RY3 as sole C-source, and it was very sensitive to chloramphenicol. Besides, strain RY3 grew fastest at 55℃~65 and 0℃~2% NaCl. Characteristics of modality and physiology with sequence analysis of the 16s rDNA gene of strain RY3 preliminarily showed that it was Methanothermobacter thermautotrophicus. The experiments indicated that the time which began to produce methane with the highest velocity could be shortened two third by adding RY3 in one week, and the total methane production also was 1.8 times than before. Strain SH4 possessed wide scale of growing pH(5.5~9.5)and excellent ability of acclimatizing itself to acid-alkali. The methane production had no apparent difference among those cultivated in different initial pH(6.0~8.0)after three days and equaled to the maximum production basically. Cells of SH4 were G+, short-rod sharp, monothetic and nonmotile. The colony was pale yellow with suborbicular-shape. Formate or H2+CO2 but not acetate was utilized by SH4 as sole C-source, and it was very sensitive to chloramphenicol. Besides, it grew fastest at pH 7.0,55 ℃~65 and 0℃~2% NaCl concentration. The experiment indicated the time that began to produce methane could be shortening one third by adding SH4. And the total methane production also rose apparently. Characteristic of modality and physiology with sequence analysis of the 16S rDNA gene of strain SH4 demonstrated it was Methanobrevibacter arboriphilus. The activated sludge was utilized as fixture, mixed with culture medium and inocolum, that the solid compound inoculum could be produced by anaerobic fermentation. The compound inoculum could grow between pH 5.5~9.5, 15℃~65. It demonstrated the compound inoculum ha℃ve great ability of adapting to circumstance. In the experiment that making pig manure be substrate and taking the anaerobic sludge producing methane that cultured in long term in laboratory to be comparison, the concentration of methane in fermentation added compound inoculum almost equal to the comparison at 20℃, but the volume of gas production could be a little higher. The gas production everyday inoculated compound inoculum was 1.59 times to comparison. The time that the concentration of methane to maximum could be shortening by two third by adding compound inoculum, and the total gas production was 2.7 times to comprison while the total methane production was 2.8 times. If take the no inoculum be the comprasion, anaerobic fermentation added compound inoculum made the concentration of methane to 50% in 2 weeks but the comparison only to 4.3% at 20℃. The time that the concentration of methane to 50% by adding compound inoculum only need 1 week, but the comparison need 2 weeks at 50℃.