80 resultados para MDH


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采用聚丙烯酰胺凝胶不连续系统电泳方法分析了泥鳅和大鳞副泥鳅不同交配组合、不同核质关系下,胚胎发育阶段(0~145 h) 酯酶(EST) 和苹果酸脱氢酶(MDH) 同工酶的分化表达谱式。EST 同工酶随细胞质、细胞核不同及胚胎发育各个时期具有不同的个体发育谱式。以泥鳅卵子为细胞质环境的Ⅰ、Ⅱ两组,杂交组( Ⅱ) 的EST同工酶基因在受精后3 min 至原肠中期,雄核基因参与表达与调控。以大鳞副泥鳅为细胞质环境的Ⅲ、Ⅳ两组,各酶均以细胞质调控为主。MDH 同工酶在各组合及各个发育阶段均未表现出实质性差异,发现

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Lemna minor is a small aquatic polyploid angiosperm which reproduces apomictically and has a worldwide distribution. This study was vmdertaken to characterize the extent and nature of phenotypic variability. The techniques of starch gel electrophoresis were used in this investigation and. MDH phenotypes of several populations from Ontario, USA and Africa were examined and compared. Heat stability, molecular weight and cell fractionation analyses were also done to identify locus specific MDH bands. The results of the population surveys suggest that there is little genetic variability present both within and between Lemna minor/Lemna turionifera . Evidence of correlation of physiological and seasonal variation patterns was found.

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A Annona cherimola é um fruto exótico, com um sabor agradável. Este fruto tem um elevado potencial comercial, mas apresenta um tempo médio de vida curto devido ao seu rápido amadurecimento. Por esta razão é necessário conhecer melhor o processo de amadurecimento deste fruto. Na Região Autónoma da Madeira a cultura da anoneira é muito importante em termos comerciais. O processo de amadurecimento leva a diversas modificações bioquímicas e fisiológicas. Existem várias enzimas e substâncias que integram este processo. Neste trabalho iremos estudar os genes das enzimas malato desidrogenase e H+ ATPase vacuolar que estão envolvidos no processo de amadurecimento dos frutos. Utilizando as técnicas de RACE e sequenciação foi possível determinar a sequência nucleotídica do cDNA destes genes. O cDNA da malato desidrogenase é composto por 1364 nucleótidos, contendo uma zona 5’ UTR com 84 nucleótidos, uma zona 3’ UTR com 284 nucleótidos e um sinal de poliadenilação com a sequência AATAAA. A ORF apresenta 996 nucleótidos, codificando uma proteína com 332 aminoácidos. Para a H+ ATPase vacuolar foi amplificado o cDNA da subunidade C do domínio V1. Esta apresenta 799 nucleótidos, dos quais 36 são da 5’ UTR, 266 da 3’ UTR e 498 da ORF. A ORF codifica uma proteína com 166 aminoácidos.

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Mode of access: Internet.

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Ultraviolet (UV) radiation is one of the major risk factors of cataract (loss of eye-lens transparency). The influence of UVB radiation (300 nm, 100 mu W cm(-2)) on the activity and apparent kinetic constants (K-m and V-max) of rat lens hexokinase (HK;EC2.7.1.1), phosphofructokinase (PFK;EC2.7.1.11), isocitrate dehydrogenase (ICDH;EC1.1.1.41) and malate dehydrogenase (MDH;EC1.1.1.37) of energy metabolism has been investigated by irradiating the lens homogenate of three-and 12-month-old rats. In the three-month-old group specific activities of HK and PFK are reduced by 56 and 43 %, respectively, and there is no change in ICDH and MDH activities after a 24 h exposure. On the other hand, in the 12-month-old group the decreases are 72, 71, 24 and 16 % for HK, PFK. ICDH and MDH, respectively. UVB irradiation increases the apparent K-m of HK and PFK (in both age groups), whereas the K-m of ICDH and MDH is not altered. While the decrease in V-max of these enzymes due to UVB exposure is only marginal in three-month-old rats, it is more pronounced (significant) in 12-month-old rats. A similar decrease in enzyme activities of HK and PFK is also observe upon UVB exposure of the intact rat lens. The photoinduced changes in energy metabolism may in turn have a bearing on lens transparency, particularly at an older age.

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This submission addresses the problem of housing price inflation, the chronic under-supply of new housing stock, and the resultant decline in housing affordability for low and middle income households. It specifically focusses on the supply of medium density housing (multi-unit development) in Melbourne, although we believe that the observations made about housing in supply in Melbourne are relevant in other urban centres and to other types of housing supply. In terms of medium density housing (MDH) our concern also extends to the poor quality and design. Why the market tends to deliver generic apartments of poor quality and design which are uncompetitive with lower density housing and amenity despite planning objectives, and how this apparently intractable problem can be overcome is the topic of this submission...

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One of the problems associated with outdoor polymeric insulators is tracking and erosion of the weathershed which can directly influence the reliability of the power system. Flame retardants are added to the base material to enhance its tracking and erosion resistance. Hydroxide fillers are regarded as the best flame retardants. This paper deals with studies related to nano - sized magnesium dihydroxide (MDH) and micron-sized Alumina Trihydrate (ATH) fillers as flame retardants in RTV silicone rubber. Tracking and erosion resistance studies were carried out on MDH and ATH silicone rubber composites using an inclined plane tracking and erosion (IPT) resistance tester. The MDH filled (5% by wt) composites performed much better than ATH composites in terms of eroded mass, depth of erosion, width and length of erosion. The eroded mass of MDH composite is 49.8 % that of ATH composite which can be attributed to high surface area and higher thermal stability of MDH nanofillers.

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A total of 63 isolates of Pasteurella multocida from Australian poultry, all associated with fowl cholera outbreaks, and three international reference strains, representing the three subspecies within P. multocida were used to develop a multi-locus sequence typing scheme. Primers were designed for conserved regions of seven house-keeping enzymes - adk, est, gdh, mdh, pgi, pmi and zwf - and internal fragments of 570-784 bp were sequenced for all isolates and strains. The number of alleles at the different loci ranged from 11 to 20 and a total of 29 allelic profiles or sequence types were recognised amongst the 66 strains. There was a strong concordance between the MLST data and the existing multi-locus enzyme electrophoresis and ribotyping data. When used to study a sub-set of isolates with a known detailed epidemiological history, the MLST data matched the results given by restriction endonuclease analysis, pulsed-field gel electrophoresis, ribotyping and REP-PCR. The MLST scheme provides a high level of resolution and is an excellent tool for studying the population structure and epidemiology of P. multocida.

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Genetic variation of Contracaecum ogmorhini (sensu lato) populations from different otariid seals of the northern and southern hemisphere was studied on the basis of 18 enzyme loci as well as preliminary sequence analysis of the mitochondrial cyt b gene (260 bp). Samples were collected from Zalophus californianus in the boreal region and from Arctocephalus pusillus pusillus, A. pusillus doriferus and A. australis from the austral region. Marked genetic heterogeneity was found between C. ogmorhini (sensu lato) samples from the boreal and austral region, respectively. Two loci (Mdh-2 and NADHdh) showed fixed differences and a further three loci (Iddh, Mdh-1 and 6Pgdh) were highly differentiated between boreal and austral samples. Their average genetic distance was DNei = 0.36 at isozyme level. At mitochondrial DNA level, an average proportion of nucleotide substitution of 3.7% was observed. These findings support the existence of two distinct sibling species, for which the names C. ogmorhini (sensu stricto) and C. margolisi n. sp., respectively, for the austral and boreal taxon, are proposed. A description for C. margolisi n. sp. is provided. No diagnostic morphological characters have so far been detected; on the other hand, two enzyme loci, Mdh-2 and NADHdh, fully diagnostic between the two species, can be used for the routine identification of males, females and larval stages. Mirounga leonina was found to host C. ogmorhini (s.s.) inmixed infections with C. osculatum (s.l.) (of which C. ogmorhini (s.l.) was in the past considered to be a synonym) and C. miroungae; no hybrid genotypes were found,confirming the reproductive isolation of these three anisakid species. The hosts and geographical range so far recorded for C. margolisi n. sp. and C. ogmorhini (s.s.) are given.

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通过野外观察,发现羽叶铁线莲Clematis pinnata Maxim.在形态上相似于短尾铁线莲C. brevicaudata DC.及大叶铁线莲C. heracleifolia DC.,推测羽叶铁线莲为后二者杂交产生。本文从形态学、解剖学、孢粉学、分子生物学等方面寻找证据,为这一推测寻找证据: 1. 形态学 通过野外观察结合标本馆工作,对这三个种的外部形态性状及其变异进行全面的分析,以探讨羽叶铁线莲C. pinnata在形态上与二假定亲本的异同及其产生原因。发现花、叶、习性等性状,在二假定亲本种种内稳定,但种间差异很大,在羽叶铁线莲中,性状变异的幅度正是处于二假定亲本差异之间。 2.解剖学 在光学显微镜及扫描电镜下,观察了这三种铁线莲的叶表皮特征,结果表明:叶片上表皮均不具有气孔器,下表皮气孔器类型均为无规则型;表皮细胞多为不规则形,仅在短尾铁线莲C. brevicaudata的上表皮中为近多边形;上表皮角质膜均具细条纹,下表皮角质膜均具环状或放射状波状嵴。 在扫描电镜下对瘦果形态及宿存花柱进行观察,结果表明:瘦果均密被长柔毛,并有蜡质颗粒状附属物。 在三个种植物之间叶表皮和瘦果的特征均无明显差别,对解释所讨论的问题意义不大。 3.孢粉学 在扫描电镜下对这三种铁线莲的花粉粒进行观察,结果表明:短尾铁线莲的花粉粒具三沟;大叶铁线莲的杂性株中花粉高度败育,说明其杂性株其实即为雌株;羽叶铁线莲的花粉也高度败育,但本种均为两性株,支持本种为杂交种的推测。 4.等位酶研究 利用莽草酸脱氢酶SKD和苹果酸脱氢酶MDH对采自3个居群的羽叶铁线莲大叶铁线莲和短尾铁线莲进行等位酶试验,结果显示在短尾铁线莲与大叶铁线莲中分别出现种内一致的谱带,而羽叶铁线莲则显示出二者杂合的带型。这一结果有力的支持了羽叶铁线莲是由短尾铁线莲和大叶铁线莲杂交产生的推测。 5.居群遗传结构分析 利用随机扩增多态性DNA标记(RAPD)分别检测三个种的遗传多样性和居群遗传结构。15个随机引物对这三个种共160个个体 (短尾铁线莲C. brevicaudata 五个居群73个个体;大叶铁线莲Clematis heracleifolia五个居群75个个体;羽叶铁线莲Clematis pinnata三个居群12个个体。)进行分析,总共得到123个用于分析的条带。我们对这三个种扩增出的条带按照居群进行了聚类分析,结果表明这三个种在聚类树上能够很好的区分开,但是种内居群间没有表现出地理分布式样方面的信息;个体水平上聚类结果表明,百花山采到的7株无法确定的铁线莲幼苗有6株是短尾铁线莲C. brevicaudata另外一株是羽叶铁线莲Clematis pinnata,这说明在幼苗形态上二者差别不大;我们对这三个种分别进行了居群遗传结构的分析,结果表明:短尾铁线莲C. brevicaudata的多态条带比率为90.65%,遗传变异主要分布在居群内,居群间分化较小,而大叶铁线莲Clematis heracleifolia的多态条带比率为90.76%,居群间遗传变异占30.52%,居群间有明显分化。羽叶铁线莲Clematis pinnata的遗传多样性很低,有可能是由于营养繁殖造成的。 6.DNA序列分析 选取叶绿体基因组的trn L-F序列和核基因组的ITS序列进行了测序分析。发现从三个种十个个体得到的trn L-F序列之间几乎没有差异,在640 bp中只得到了3个信息位点。对ITS测序过程中发现短尾铁线莲可直接用PCR产物测序,而对大叶铁线莲和羽叶铁线莲必须进行克隆测序,由于时间关系,我们得到的序列不足以进行进一步分析。 基于以上研究结果,我们初步认为羽叶铁线莲是通过短尾铁线莲和大叶铁线莲的杂交而起源,并根据我们观察到的变异式样对羽叶铁线莲系的一些种类进行了分类学处理。

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植物远缘杂交是作物育种实践及其相关的基础遗传中应用最广泛的技术之一,几乎涉及到所有与栽培作物有关的科属内相对近缘的植物种类。除核型稳定的种间杂交可得到杂种外,还可以利用核型不稳定的种间杂交过程中父本染色体全部被消除的现象,通过胚培养和加倍处理获得大量的双单倍体(DH)杂交后代。然而,这种从小麦与玉米杂交获得的小麦DH后代与其理论上应完全同质的遗传表现却不相符,总有2-5%的DH植株发生了形态学变异,虽然没有明显的来自玉米的性状特征,而且一些研究者也认为它们是配子无性系变异,但是,不论是理论上还是一些间接的细胞学和生化证据都表明,有玉米的染色体DNA通过受精过程转移到小麦DH后代的基因组中,然而到目前为止,仍缺乏DNA水平上的直接证据。 本文在对来自小麦 * 玉米的谱通小麦DH系进行生化分析取得初步证据的基础上,构建玉米的随机基因组文库,从中筛选玉米的重复DNA序列作探针分别对普通小麦和波斯小麦的DH群体进行了系统的RFLP分析,并用有关的玉米重复列克隆对一些禾本科种和不同的玉米生物型基因组进行了比较研究,主要结果如下: 1、八种同工酶电泳分析表明,MDH、ADH、GDH、SKDH4种脱氢酶和GOT在后代中没有检测到任何变异,但21株普通小麦的DH后代群体中有7株在PER同工酶的慢区出现了增加一条酶带的变异,这条带在亲本小麦和玉米中均没有,它们与通常报道的无性系变异十分类似。其中有一株(第4号株)在迁移率为0.22的位置上出现了一条小麦所不具有的酶活性较强的EST带,在玉米同迁移率的位置上也有一条带,但活性十分微弱。此外,大部分小麦DH后代的AMY同工酶恬性有十分明显的增强。 2、可溶性蛋白质的SDS-PAGE分析,在小麦的DH后代中,有几株的变异很明显,其中第4、7、19号株(图2)在分子量为43000道尔顿的位置上出现了和玉米同迁移率而小麦不具有的蛋白质带,这强烈地暗示了玉米DNA的确通过受精作用导入小麦。 3、构建了玉米的随机基因组文库,依据菌落原位杂交结果,从中挑出了500个重组克隆。用其中的100个强信号的重复DNA克隆为探针对亲本小麦和玉米进行了RFLP筛选,其中80多个为玉米基因组特异的,9个与小麦有部分同源性,随后用它们探针分别对两个小麦DH群体进行RFLP分析。 4、用上文筛选的玉米特异的重复DNA克隆作探针进行RFLP分析,只有玉米的MR64克隆同时导入到两个小麦群体的各一株后代中,即普通小麦DH系的18号株和波斯小麦DH系的15号株检测到强杂交信号;另外一个克隆MR72只在4株波斯小麦DH后代中有杂交信号,这个结果首次从DNA水平上证明,的确有某些玉米特异的DNA序列通过受精作用以很低的频率转移到小麦DH后代的基因组中。 5、与小麦有部分同源性的玉米克隆MR13和MR50在一些普通小麦DH后代中检测到了缺失变异。特别是用MR13在普通小麦DH系的18号株(即导入了玉米特异的MR64的DNA的那一株小麦DH后代)的基因组中检测到了大幅度的限制性片段长度的变化,即原来的4.3kb的强信号带消失了,取而代之的是增加40kb、15kb、2.5kb和2.0kb四条杂交带,这要么与小麦基因组DNA较大的重俳事件有关,要么是由外源的玉米DNA插入造成的,但从增加的片段长度如此之大以及杂交信号变弱来看,它很可能就是玉米DNA插入到这个较强信号的小麦单拷贝序列中的结果。用小麦的DNA克隆pTa71也检测到了明显的变异。 6、测序分析发现,克隆MP64的插入片段长度为695bp,A+T含量为58%,经在GENEBANK中检索证实它是一个新克隆的DNA序列。序列中分别含有两对正向和反向重 序列及三个回文序列,对多种酶切的玉米基因组的RFLP分析表明它是一个带1-3个主串联重复单位的散布重复序列,在序列中的CCGG的第二个C高度甲基化,拷贝数约为5600左右。染色体原位杂交表明,MR64在玉米的每条染色体上均有分布,但拷贝数不同,这暗示它可能与玉米基因组的演化历程有密切的关系。 7、比较分析发现,MR64是玉米基因组特异的;而MR72在高粱、珍株粟、糜子和狼尾草等四个和玉米较近缘的种的基因组中有部分同源序列,这个比较结果更加肯定了小麦DH系所新增的DNA序列的确是异源的玉米DNA通过受精过程导入的。 8、初步分析发现,玉米的卫星DNA克隆MR4和其它卫星DNA一样也有严谨的重复等级结构,而且在主要禾本科种基因组中有较低的同源性。经在GENEBANK检索,串联重复DNA克隆MR68是一个新克隆的DNA序列,它在不同的玉米生物型基因组中表现出明显的分化特征,可用它作进一步的基因组的比较分析。 9、本文对染色体消除过程度中异源小片段DNA导入的可能机制和散布重复序列在远缘杂交的异源DNA鉴定中的应用进行了讨论,并分析了染色体消除型远缘杂交所获得的DH后代的变异来源。

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  氮素是植物光合生产的决定性因素,尤其是在沙地草地生态系统中,氮素贫乏往往限制植物的生长发育。因此,研究沙地植物光合作用与叶片N含量之间的关系,以及不同植物功能型氮素利用效率,有助于理解不同植物资源利用效率的差异。以浑善达克沙地分布的80种植物为研究对象,对不同生境(固定沙丘、丘间低地和湿地)、不同生活型(乔、灌、草)、不同光合途径(C3和C4)以及豆科和非豆科植物等功能型进行研究,结果表明:无论在单位叶面积水平还是单位干重水平上的叶片氮含量,均与光合速率成极显著正相关,但单位氮素的光合利用效率在不同生境以及不同功能型之间差异很大;光合氮素利用效率表现为:湿地植物>沙丘>丘间低地植物;草本植物>灌木>乔木;C4草本>C3草本植物,非豆科植物>豆科植物。   为了验证浑善达克沙地豆科植物是否比非豆科植物具有更高的光合潜力,我们比较研究了3种优势豆科植物小叶锦鸡儿(Caragana microphylla)、木岩黄芪(Hedysarum fruticosum var. lignosum)、披针叶黄华(Thermopsis lanceolata)和2种非豆科植物羊草(Leymus chinensis)和黄柳(Salix gordejeviii),结果表明并非所有豆科植物都比非豆科植物有着显著高的光合速率,仅木岩黄芪表现出较高的光合速率,其它两种豆科植物的光合速率和羊草、黄柳的差异并不显著(P>0.05),甚至低于后者,这是因为氮素利用效率(PNUE)在其中起关键作用,通过对影响PNUE的几个主要因素进行分析得出:叶绿素对光能的吸收、光化学转换效率和CO2分压并不是构成豆科和非豆科植物PNUE差异的主要因素,而Rubisco羧化效率决定了所实验的5种植物对氮素利用效率的高低。   木岩黄芪在浑善达克沙地的沙丘上为优势种,甚至成为流动沙丘的先锋种。除了其显著高的氮含量外,对沙丘胁迫生境的光合适应性是我们关注的另一个重点。通过对木岩黄芪和其伴生种黄柳的光反应曲线以及光合日动态的研究,发现木岩黄芪具有显著高的光合速率、水分利用效率和PSII 光化学效率,其忍受中午强光和高温的能力较强(即“光合午休”现象不明显)。另外,该物种还表现出了显著高的光饱和点和低光补偿点。 对木岩黄芪的模拟降雨试验结果表明:气体交换参数以及叶绿素荧光参数均受到干旱和模拟降雨的影响,其中气孔因素和非气孔因素共同决定了干旱条件下木岩黄芪光合速率的降低;但降雨解除干旱后,气孔导度恢复较快,而PSII 潜在活性和PSII 光能转换效率的恢复却比较缓慢。在0-15mm的降雨量范围内,随降雨量的增加各项生理指标不断升高,但大于15mm的降雨量对木岩黄芪影响不大,因此木岩黄芪可被视为低耗水型植物。   对木岩黄芪光合酶的研究结果表明,其C4光合酶的活性很高,磷酸稀醇式丙酮酸羧化酶(PEPcase)、NAD-苹果酸酶(NAD-ME)、NADP-苹果酸酶(NADP-ME)、NAD-苹果酸脱氢酶(NAD-MDH)、NADP-苹果酸脱氢酶(NADP-MDH) 和丙酮酸磷酸双激酶(PPDK)等酶的活性,在整个生育期内为黄柳的5倍以上,但稳定性碳同位素测定结果却表明木岩黄芪为C3植物。因此,我们认为C3豆科植物木岩黄芪体内可能存在着C4光合途径,这种机制使得其对于流动沙丘的胁迫环境有着很强的适应性和很高的资源利用效率。

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本论文由三部分组成,一、大豆高产品种黑农40与低产品种黑农37不同发育时期叶片光合功能的比较研究。二、大豆非叶器官豆荚的光合特性。三、不同大豆品种叶片和非叶器官光合特性的比较分析。 一、 黑农40和黑农37不同发育时期叶片的光合特性。 以不同产量水平的东北大豆黑农40和对照品种黑农37为试验材料,研究了从幼苗期到衰老期五个不同发育时期叶片光合作用特性的变化。尤其是比较系统地研究了C4途径的表达,并通过相关分析,发现C4途径酶的活性与大豆的光合效率及其产量密切相关。主要研究结果如下: 1.测定不同发育时期大豆叶片净光合速率、DCIP光还原活力和1,5-二磷酸核酮糖羧化酶(RuBPcase)活力,结果表明,黑农40和黑农37叶片净光合速率均在初荚期达到最高值,而且不同发育时期的黑农40叶片光合能力均强于黑农37。 2.随着大豆叶片的发育和衰老,其叶绿素、类胡萝卜素的含量及Chla/b比值有一个逐渐升高,而后降低的过程。在同一发育时期,高产高光效品种黑农40光合色素含量均高于黑农37,有助于黑农40捕获更多的光能供光合作用所利用。 3.叶绿体吸收光谱及四阶导数光谱表明在整个生育期内以初荚期叶片对光能的吸收能力最强;而每一个发育时期黑农40叶片对光能吸收的能力均比黑农37高。荧光动力学参数表明,高产大豆黑农40叶片PSII活性(Fv/Fo),光化学猝灭系数(qP)及PSII总的光化学量子产量也均高于对照品种黑农37的相应值:而黑农40的非光化学猝灭系数(qN)低于黑农37。说明高产大豆叶片具有与产量潜力相关的较高光能吸收和原初转化能力。通过对叶片及其叶绿体低温(77K)荧光发射光谱特性的分析表明,黑农40叶绿体对两个光系统之间激发能的调节能力优于黑农37。总之,黑农40对光能的吸收、传递和转化能力高于黑农37,从而能为碳同化提供更多能量。 4.通过研究苗期、开花期、初荚期、鼓粒期和衰老期等发育阶段的黑农40和黑农37叶片中磷酸烯醇式丙酮酸羧化酶(PEPCase)、NADP-苹果酸脱氢酶(NADP-MDH)、NADP-苹果酸酶(NADP-ME)、丙酮酸磷酸双激酶(PPDK)等C4途径的关键酶的活性变化,结合同位素14CO2喂饲试验,证明两种大豆叶片均含有C4途径四种关键酶,其原初产物含有有限的有机酸,说明有C4循环存在;而从PEPCase/RuBPcase的比值看,C4途径的酶在黑农40叶片中表达较高。通过相关分析,我们发现Pn与PSII光化学活性,RuBPCase及C4酶活性密切相关。这些结果还暗示有可能通过检测C4途径酶的表达水平及比例,筛选出具有高产潜力的大豆种质。 二、大豆非叶器官豆荚的光合特性。 通过对大豆非叶器官豆荚光合特性的研究,结果表明大豆豆荚的光合能力在鼓粒期达到最高值。通过叶绿体吸收光谱、荧光动力学和低温荧光等测定技术,我们发现鼓粒期的豆荚对光能的吸收、传递和转化有更高的能力;在鼓粒期不同品种的豆荚色素的含量也较高,从而有利于捕获更多的光能,供光合作用利用。DCIP光还原活力的测定结果表明鼓粒期豆荚也具有较高光合能力。 通过对大豆的初荚期、鼓粒期和衰老期豆荚RuBPCase和四种C4途径酶活性的研究,不仅证明非叶器官中有高活性的C4途径酶和存在有限的C4途径,而且鼓粒期豆荚有较高的碳同化效率。 三、不同大豆叶片和非叶器官光合特性的比较分析。 对三种大豆叶片、豆荚、种皮和子叶的色素含量和Chla/b进行测定,利用光谱技术、荧光技术及RuBPCase活性的测定,分析了大豆不同器官的光合特性。试验结果证明,非叶器官具有与叶器官相似的光合性能。与叶片比较,表明在非叶器官中具有非常高的C4酶活性。有利于补偿叶片开始衰老光合作用衰退的不足,因此非叶器官的这些光合特性有助于增加大豆光合产物的积累。

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采用水平式淀粉胶电泳技术 ,对云南龙陵黄山羊、宁蒗黑头山羊、马关无角山羊和路南圭山羊等 4个保种山羊的 1 2 0个个体共 3 9个基因座位的基因多态性进行了研究。结果显示 ,云南 4个保种山羊品种在AKP、CES - 1、ESD、GOI、LAP、MDH、ME和NP基因座位出现多态。多态座位基因在不同保种山羊中分布不同。多态基因座位百分比 (P)在 4个保种山羊中分别为 0 .2 0 51 ,0 .1 53 8,0 .1 2 82和 0 .1 53 8。平均杂合度 (H)分别为 0 .0 95,0 .0 61 4 ,0 .0 4 67和 0 .0 662。用UPGMA法对由基因频率计算得到的Nei氏标准遗传距离进行聚类分析 ,结果表明云南保种山羊具地理分布及品种特点 ,龙陵黄山羊和其它 3个品种的遗传距离最远。