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随着工业化的发展,大气中二氧化碳的浓度(CO2)预测从现在的平均350μmol·mol-1升高到2030年的570μmol·mol-1,其增温作用将持续多个世纪。植被在大气二氧化碳减排以及调控区域水热状况过程中起重要作用,而其机理过程目前十分不清楚。本实验应用自控、封闭、独立生长室,研究了CO2浓度和温度升高对红桦根、茎、叶和枝可溶性蛋白含量和分配的影响,从蛋白水平上来解释川西亚地区的建群种-红桦对CO2升高和温度升高及其交互作用的响应规律,为全球气候变暖川西亚高山的植被保护和恢复提供理论依据。研究结果表明: 1. CO2浓度升高增加了可溶性蛋白的总量,改变了可溶性蛋白分配模式,即,可溶性蛋白分配到根的比例增加,分配到茎、枝、叶的比例减少。可能意味:在CO2浓度升高条件下,红桦根系的生长和营养物质吸收功能将会增强。 2. CO2浓度升高增加了根和茎的清蛋白含量,降低了叶片的清蛋白含量,叶片的球蛋白含量、醇溶蛋白含量和谷蛋白含量均增加。表明CO2浓度升高增加了清蛋白在根中积累,球蛋白、醇溶蛋白和谷蛋白大量在叶片中积累;前人研究所指出的CO2浓度升高使植物叶片可溶性蛋白的含量降低可能仅仅是由于清蛋白含量的降低造成的。 3. 温度升高使红桦幼苗整株所含可溶性蛋白总量增加,但可溶性蛋白总量的分配因红桦幼苗器官的不同而异。温度升高下根、茎、叶和枝的分配量分别占总可溶性蛋白的27.74%、35.57%、23.00%、13.68%,即茎>根>叶>枝。对照的根茎叶枝的分配量分别占总可溶性蛋白的21.01%、41.41%、23.08%、14.50%,即茎>叶>根>枝。表明温度升高使可溶性蛋白分配到根的比例增加,有利于根的可溶性蛋白的积累,增强了根吸收水分和矿质营养的能力,从而有利于根系的生长。 4. 温度升高处理下清蛋白和球蛋白在根中含量升高,在茎、叶和枝中含量下降,但没有达到显著水平;醇溶蛋白在根和叶中含量显著增加;谷蛋白在茎中的含量显著降低。表明温度升高增加清蛋白和球蛋白在红桦幼苗根部的积累,也有利于根和叶醇溶蛋白的积累,但不利于谷蛋白在茎的积累;温度升高条件下叶片可溶性蛋白升高是醇溶蛋白在叶片中积累的结果。 5. CO2浓度和温度同时升高条件下红桦幼苗的可溶性蛋白总量增加很少,只有分配到茎的可溶性蛋白比例增加,并且对可溶性蛋白分配规律没有影响。CO2和温度同时升高下红桦幼苗枝的可溶性蛋白含量的降低是可溶性蛋白总量的降低而不是碳水化合物稀释的结果,并且CO2和温度同时升高对红桦幼苗的生长没有明显的促进作用。 6. CO2和温度同时升高处理对可溶性蛋白含量有显著影响。清蛋白含量在根、茎、叶和枝中均降低,球蛋白含量在根中显著降低,醇溶蛋白含量在根、茎、叶和枝中均降低,谷蛋白含量在根中显著降低。表明CO2浓度和温度同时升高对根的影响显著,即降低了根的可溶性蛋白含量,可能导致根的吸收能力下降。 7. 因此,CO2和温度同时升高对可溶性蛋白影响不能简单地通过CO2和温度单因子影响机理来解释。 It is well known that atmospheric CO2 concentration and temperature are increasing as a consequence of human activities. Atmospheric CO2 concentration are predicted to increase from 350μmol·mol-1 now to 570μmol·mol-1 2030. And temperature will continue to increase for several centuries as a result of CO2 enrichment. Vegetation play a key role in reducing atmospheric CO2 and adapting and controlling warter and energy process in a certain region, while the underlying mechanism are not clear, yet. Betula albo-sinensis, as the dominating tree species of subalpine dark coniferous forest in west Sichuan province, play an important role in determing structure and function of forest ecosystem. In our study, effects of elevated atmospheric CO2 concentration (ambient±350±25μmol·mol-1), increased temperature (ambient±2.0±0.5℃) and their combination on contents and allocation of soluble protein were studied in independent and enclosed-top chamber system under high-frigid conditions. Chambers with ambient CO2 concentration and temperature are taken as control. The results are as the following, 1) Elevated atmospheric CO2 increased the accumulation of total weight of soluble protein in whole plant and changed allocation of soluble protein in red birch by increasing its allocation to roots and reducing its allocation to stem. This caused much more accumulation of soluble protein in roots which might help to prompt growth, development and nutrient absorption ability of roots. 2) Treatment EC increased content of albumin in roots and stems, reduced the content of albumin in leaves, and increased the content of globulin, promalin and glutenin in leaves. That is to say EC increased the accumulation of albumin in roots and accumulation of globulin, promalin and glutenin in leaves. The reduced soluble protein contents in plant leaves by EC, as reported by former researchers, are mainly resulted from the reduced content of albumin in leaves. 3) Elevated temperature increased the total of soluble proteins, but its allocation was dependent on organs. In treatment ET, roots, stems, leaves and branches take 27.74%, 35.57%, 23.00% and 13.68% of total weight of soluble protein. In treatment CK, roots, stems, leaves and branches take 21.01%, 41.41%, 23.08% and 14.50%. Elevated temperature changed allocation of soluble proteins in that it stimulated soluble proteins accumulation in roots and improved the uptake of water in roots. 4) Treatment ET increased the content of albumin and globulin in roots, and reduced the content of albumin and globulin in stems, leaves and branches. The content of promalin in roots and leaves was increased significantly, and the content of glutenin in stems was reduced significant. This suggested that ET stimulated the accumulation of albumin and globulin in roots and accumulation of promalin in leaves and roots; that treatment ET increased content of soluble protein in leaves was mainly resulted from the increased promalin content in leaves. 5) Regarding treatment ETC, the total of weight of soluble proteins increased, but not significantly; but increased in stems. So the combination of elevated atmospheric CO2 and temperature had not changed the allocation of soluble proteins in red birch seedling and reduced soluble proteins in branches were not the result of increased carbohydrate. 6) Treatment ETC reduced the content of albumin and promalin in roots, stems, leaves and branches, reduced the content of globulin and glutenin in roots significantly. That is to say elevated atmospheric CO2 and temperature reduced the content of soluble proteins in roots significantly which might help to prompt growth, development and nutrient absorption ability of roots. 7) The effects of elevated atmospheric CO2 and temperature on soluble protein cannot be simply interpreted through their mechanism that obtained when they were imposed on plant separately.

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土地利用是人类根据土地质量特性来开发利用土地,创造财富,满足人类生产和生活的需要,同时改善环境,满足人类生存需要的过程。土地利用总体规划是对未来各类用地在空间上、时间上作出总体的协调的预先安排,不仅受到一定历史背景的制约,同时也受影响于当前的社会经济发展情况。但是,国内传统的土地利用总体规划往往从狭窄的技术经济观点出发,对远期的生态环境问题、社会问题缺少考虑,将新的用地尽量安排在最便捷、最经济的地方。 由于土地利用总体规划对环境影响具有长期性、复杂性、综合性、有时还有不可逆转性等特点,迫切需要在编制土地利用总体规划时对规划区与土地利用有关的环境影响进行科学研究,把环境保护纳入土地利用活动的计划、决策和规划实施中,促进土地资源持续、协调的利用。为更好地进行土地利用总体规划环境影响评价必须首先建立相应的评价指标体系,而目前国内关于该项研究的理论和实践的相关报道都较少。 本论文在综述国内外土地利用总体规划环境影响评价的理论与实践的基础上,在国内第一批开展了相关领域的案例研究,采用理论研究和案例分析相结合的研究方法对土地利用总体规划环境影响评价方法和指标体系进行了研究,对邛崃市土地利用总体规划进行了环境影响评价,其研究的主要内容和论点如下: (1)第一次根据FAO 确定的五大原则,引入了生态用地的概念并按照价值模型构建了以土地资源可持续利用为目标的县级土地利用总体规划环境影响评价的指标体系。以生产性、稳定性、保护性、经济活力、社会可接受性五个方面作为指标层来度量土地利用总体规划的环境影响,并选取了土地利用率、土地整理率、水面指数、生态用地面积比例、耕地转化率、建设用地产值指数、公众满意度等21 个元指标作为具体的评价指标。该指标体系强调了规划方案的公众参与,便于充分吸收公众的意见和建议;并且评价指标获取容易,实用性较强。 (2)在土地利用总体规划环境影响评价方法上进行了有益的探索和尝试,由于土地利用总体规划环境影响评价的主要对象是几个拟定的规划方案,所以采用综合评分法(包括特尔斐法和层次分析法)和公众参与相结合的评价方法。应用上述指标体系和评价方法对邛崃市土地利用总体规划的三个方案进行了评价筛选,高方案最终得分为92.049;中方案最终得分为91.028;而低方案最终得分为95.541,为最优方案。 (3)开展了对土地利用总体规划替代方案和公众参与机制的研究,对公众参与的方式、程序及主要内容从理论和实践两方面进行了有益的尝试,收到了良好的效果。 (4)对邛崃市土地利用总体规划进行了环境影响评价,根据邛崃市的具体情况,对规划实施后可能造成的环境正、负面影响进行了分析和预测,提出了预防或者减轻不良环境影响的对策和措施。 Land use is a process, which is to develop land according to its mass property. Bycreating the wealth and improving the environment, it can meet the need of production,life and human survival. Land use planning, as a planning form to guide land use, issubject to the historical background, and influenced by development of economic andsociety. The land use planning in the past, from narrow economic technology view,lacking of concerning ecologic environmentand social problem, arranged new land in the most convenient and economic place. Because of complexity, comprehensive and sometimes irreversible characteristicsof environmental impact caused by land use planning which has been implemented, it isneed to carry on scientific research on environmental impact related to land use as theland use planning is forming, to bring environmental protection within the plan, policymaking and implementing of land use activity, promoting the sustainment, harmonious use of land resource. This paper, taking the readjustment of land use planning in Qionglai as an example,assessed its environmental impact of land use planning. The main contents and results arepresented as follows: (1) On the basis of the five criterions of AFO, for the first time propose county classoverall planning of land uses SEA index by inducting ecological land use andestablishing the Value factor system, according to Productivity criterion,Stabilitycriterion,Sheltered criterion,Economic livingness criterion,Social acceptabilitycriterion,the environmental impact of land use system was assessed by using Valuemodel. Through identifying the factors of environmental impact of land use planning, thepaper established the factor system of SEA of land use planning. From the land usefactors, 21 factors was chosen to assess the environmental impact degree of land useplanning, such as, index of land use degree, the rate of land collating, index of watersurface, the rate of ecological use land, cultivated land conversion ratio, forest landconversion ratio, public satisfaction degree and so on. These indexes make a point thatpublic participation of plan project fully absorb public idea and propose and the index easily get, better utility. (2) Attempt useful assessment method system of SEA of land use planning. In viewof there are no or almost no inevitable contact among the factors of SEA of land useplanning,we use AHP (Analytic Hierarchy Process) as the main assess method . Thereare three plans are compared in this paper apply the foregoing index and assessmentmethod. The high plan finally score is 92.049,while the middle plan is 91.028. The lowplan score is 95.541,is the best one,as the selected plan. (3) Carry on the research of the alternative scheme of overall planing of land useand public participation,to the fashion ,procedure and object matter carry out helpfulattempt from theory to practice,the results is good. (4)Took place SEA of Qionglai County overall planing of land use,according to thecircumstance of Qionglai,we analyze and forecast the positive and negative affect afterthe plan implement,and put forward the countermeasure and means to prevent or abatebad environmental impact.

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由于人类活动所引起的地球大气层中温室气体的富集已导致全球地表平均温度在20 世纪升高了0.6 ¡æ,并预测在本世纪将上升1.4-5.8 ¡æ。气候变暖对陆地植物和生态系统产生深远影响,并已成为全球变化研究的重要议题。位于青藏高原东部的川西亚高山针叶林是研究气候变暖对陆地生态系统影响的重要森林类型。森林采伐迹地和人工云杉林下作为目前该区人工造林和森林更新的两种重要生境,二者截然不同的光环境对亚高山针叶林不同物种更新及森林动态有非常重要的影响。 本文以青藏高原东部亚高山针叶林几种主要森林树种为研究对象,采用开顶式增温法(OTCs)模拟气候变暖来研究增温对生长在两种不同光环境下(全光条件和林下低光环境)的几种幼苗早期生长和生理的影响,旨在从更新角度探讨亚高山针叶林生态系统不同树种对气候变暖在形态或生理上的响应差异,其研究结果可在一定程度上为预测气候变暖对亚高山针叶林物种组成和演替动态提供科学依据,同时也可为未来林业生产管理者提供科学指导。 1、与框外对照相比,OTCs 框内微环境发生了一些变化。OTCs 框内与框外对照气温年平均值分别为5.72 ¡æ和5.21 ¡æ,而地表温度年平均值分别为5.34 ¡æ和5.04 ¡æ,OTCs 使气温和地表年平均温度分别提高了0.51 ¡æ和0.34 ¡æ;OTCs框内空气湿度年平均值约高于框外对照,二者分别为90.4 %和85.3 %。 2、增温促进了三种幼苗生长和生物量的积累,但增温效果与幼苗种类及所处的光环境有关。无论在全光或林下低光条件下,增温条件下云杉幼苗株高、地径、分支数、总生物量及组分生物量(根、茎、叶重)都显著地增加;增温仅在全光条件下使红桦幼苗株高、地径、总生物量及组分生物量(根、茎、叶重)等参数显著地增加,而在林下低光条件下增温对幼苗生长和生物量积累的影响效果不明显;冷杉幼苗生长对增温的响应则与红桦幼苗相反,增温仅在林下低光条件下对冷杉幼苗生长和形态的影响才有明显的促进作用。 增温对三种幼苗的生物量分配模式产生了不同的影响,并且这种影响也与幼苗所处的光环境有关。无论在全光或林下低光环境下,增温都促使云杉幼苗将更多的生物量分配到植物地下部分,从而导致幼苗在增温条件下有更高的R/S 比;增温仅在林下低光条件下促使冷杉幼苗将更多的生物量投入到植物叶部,从而使幼苗R/S 比显著地降低;增温在全光条件下对红桦幼苗生物量分配的影响趋势与冷杉幼苗在低光条件下相似,即增温在全光条件下促使红桦幼苗分配更多的生物量到植物同化部分—叶部。 3、增温对亚高山针叶林生态系统中三种幼苗气体交换和生理表现的影响总体表现为正效应(Positive),即增温促进了几种幼苗的生理活动及其表现:(i)无论在全光或林下低光环境下,增温使三种幼苗的光合色素含量都有所增加;(ii)增温在一定程度上提高了三种使幼苗的PSII 光系统效率(Fv/Fm),从而使幼苗具有更强的光合电子传递活性;增温在一定程度使三种幼苗潜在的热耗散能力(NPQ)都有所增强,从而提高幼苗防御光氧化的能力;(iii)从研究结果来看,增温通过增加光合色素含量和表观量子效率等参数而促进幼苗的光合作用过程。总体来说增温对幼苗生理过程的影响效果与幼苗种类及所处的光环境有关,增温仅在全光条件下对红桦幼苗光合过程的影响才有明显的效果,而冷杉幼苗则相反,增温仅在低光条件下才对幼苗的生理过程有显著的影响。 4、增温对三种幼苗的抗氧化酶系统产生了一定的影响。从总体来说,增温使几种幼苗活性氧含量及膜脂过氧化作用降低,从而在一定程度上减轻了该区低温对植物生长的消极影响;增温倾向表明使三种幼苗体内抗氧化酶活性和非酶促作用有所提高,从而有利于维持活性氧代谢平衡。但增温影响效果与幼苗种类所处的光环境及抗氧化酶种类有关,增温对冷杉幼苗抗氧化酶活性的影响仅在林下低光环境下效果明显,而对红桦幼苗抗氧化酶活性的影响仅在全光条件下才有明显的效果。 总之,增温促进了亚高山针叶林生态系统中三种幼苗的生长和生理表现,但幼苗生长和生理对增温的响应随植物种类及所处的光环境不同而变化,这种响应差可能异赋予了不同植物种类在未来气候变暖背景下面对不同环境条件时具有不同的适应力和竞争优势,从而对亚高山针叶林生态系统物种组成和森林动态产生潜在的影响。 Enrichment of atmospheric greenhouse gases resulted from human activities suchas fossil fuel burning and deforestation has increased global mean temperature by 0.6¡æ in the 20th century and is predicted to increase it by 1.4-5.8 ¡æ. The globalwarming will have profound, long-term impacts on terrestrial plants and ecosystems.The ecoologcial consequences arising from global warming have also become thevery important issuses of global change research. The subalpine coniferous forests inthe eastern Qinghai-Tibet Plateau provide a natural laboratory for the studying theeffects of climate warming on terrestrial ecosystems. The light environment differssignificantly between clear-outs and spruce plantations, which is particularlyimportant for plant regeneration and forest dynamics in the subalpine coniferous forests. In this paper, the short-term effects of two levels of air temperature (ambient andwarmed) and light (full light and ca. 10% of full light regimes) on the early growthand physiology of Picea asperata, Abies faxoniana and Betula albo-sinensis seedlingswas determined using open-top chambers (OTCs). The aim of the present study wasto understand the differences between tree species in their responses to experimentalwarming from the perspective of regeneration. Our results could provide insights intothe effects of climate warming on community composition and regeneration behavior for the subalpine coniferous forest ecosystem processes, and provide scientificdirection for the production and management under future climate change. 1. The OTCs manipulation slightly altered thermal conditions during the growingseason compared with the outside chambers. The annual mean air temperature andsoil surface temperature was 5.72 and 5.34 ¡æ (within the chambers), and 5.21 and5.04 ¡æ (outside the chambers), respectively. The OTCs manipulation increased airtemperature and soil surface temperature by 0.51 and 0.34 ¡æ on average, respectively.Air relative humidity was slightly higher inside the OTCs compared with the controlplots, with 90.4 and 85.3 %, respectively. 2. Warming generally stimulated the growth and biomass accumulation of thethree tree species, but the effects of warming on growth and development variedbetween light conditions and species. Irrespective of light regimes, warmingsignificantly increased plant height, root collar diameter, total biomass, componentbiomass (stem, foliar and root biomass) and the number of branches in P. asperataseedlings; For A. faxoniana seedlings, significant effects of warming on all the tested parameters (plant height, root collar diameter, total biomass, and component biomass) were found only under low light conditions; In contrast, the growth responses of B.albo-sinensis seedlings to warming were found only under full light conditions. Warming had pronounced effects on the pattern of carbon allocation. Irrespectiveof light regimes, the P. asperata seedlings allocated relatively more biomass to rootsin responses to warming, which led to a higher R/S. Significant effects of warming onbiomass allocation were only found for the A. faxoniana seedlings grown under lowlight conditions, with significantly increased in leaf mass ratio (LMR) and decreasedin R/S in responses to warming manipulation. The carbon allocation responses of B.albo-sinensis seedling to warming under full light conditions were similar with theresponse of A. faxoniana seedlings grown under low light conditions. Warmingsignificantly decreased root mass ratio (RMR), and increased leaf mass ratio (LMR)and shoot/root biomass ratio (S/R) for the B. albo-sinensis seedlings grown under full light conditions. 3. Warming generally had a beneficial effect on physiological processes of dominant tree species in subalpine coniferous forest ecosystems: (i) Warming markedincreased the concentrations of photosynthetic pigments in both tree species, but theeffects of warming on photosynthetic pigments were greater under low lightconditions than under full light conditions for the two conifers; (ii) Warming tended toenhance the efficiency of PSII in terms of increase in Fv/Fm, which was related tohigher chloroplast electron transport activity; and enhance non-radiative energydissipation in terms of in increase in NPQ, which may reflect an increased capacity inpreventing photooxidation; (iii) Warming may enhance photosynthesis and advancephysiological activity in plants by increasing photosynthetic pigment concentration,the efficiency of PSII and apparent quantum yield (Φ) etc. From the results, theeffects of warming on seedlings’ physiological performance varied between lightenvironment and species. The effects of warming on photosynthesis performance of B.albo-sinesis seedlings were pronounced only under full light conditions, while thephysiological responses of A. faxoniana seedlings to warming were found only underthe 60-year plantation. These results provided further support for the observationsabove on growth responses of seedlings to warming. 4. Warming had marked effects on antioxidative systems of the three seedlings.Warming generally decreased H2O2 accumulation and the rate of O2- production, andalleviated degree of lipid peroxidation in terms of decreased MDA content, whichalleviated to some extent the negative effects of low temperature on the plant growthand development in this region; Warming tended to increase the activities ofantioxidative enzymes and stimulate the role of non-enzymatic AOS scavenging,which helped to create an balance in maintaining AOS metabolites for the threeseedlings. Nevertheless, the effects of warming on antioxidative defense systems werepronounced only under the 60-year plantation for the A. faxoniana seedlings. Incontrast, the marked effects of warming on antioxidative defense systems for the B.albo-sinesis seedlings were found only under the full light conditions. In sum, warming is considered to be generally positive in terms of growth andphysiological process. However, the responses of growth and physiology performanceto warming manipulation varied between species and light regimes. Competitive and adaptive relationships between tree species may be altered as a result of responsedifferences to warming manipulation, which is one mechanism by which globalwarming will alter species composition and forest dynamics of subalpine coniferousforest ecosystems under future climate change.

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植物群落及其环境在干扰后的演替格局和过程的研究,是群落和生态系统动态研究的一个热点。选取青藏高原东缘山原区川西云杉林皆伐后,从草地过渡到灌丛的关键阶段的4 个皆伐迹地(恢复时间为8 a、10 a、16 a 和21 a),研究皆伐及自然恢复过程对林下典型灌木银露梅(Potentilla glabra)和唐古特忍冬(Lonicera tangutica)的生长与繁殖能力的影响以及灌木植物在迹地上的更新情况,分析灌木在不同生境中的适应对策和适应能力的差异,为揭示青藏高原东缘山原区迹地植被从草甸到灌丛演替的过程和特点及促进迹地演替与植被恢复进程提供理论依据和技术支撑。研究主要结论如下:1)皆伐后银露梅生长和繁殖能力显著提高,但对唐古特忍冬的影响不明显。皆伐后银露梅丛基径、高度和各部分生物量都显著增加(P < 0.05),但唐古特忍冬只有叶生物量和地下生物量增加,总生物量和其余构件生物量无显著变化。皆伐后,银露梅的结实数量、结实株数、不结实株数和结实株/不结实株比例显著增加(P < 0.05)。自然恢复过程中,银露梅和唐古特忍冬生长能力以及银露梅的结实量都表现出降低的趋势。随着迹地自然恢复时间的增加,银露梅和唐古特忍冬的基径、高度、丛叶片数和各部分生物量有减少的趋势。银露梅的结实株数增加, 但结实数量减少。2)皆伐对银露梅和唐古特忍冬生物量分配模式影响不一致。原始林和迹地中(除CT85)银露梅的生物量大小关系皆为:地下>茎>侧枝>叶。唐古特忍冬在原始林中的生物量大小关系为:茎>地下部分>侧枝>叶,而皆伐后生物量的分配情况改变,生物量大小关系变为:地下部分>茎>侧枝>叶。随着自然恢复时间的增加,银露梅减少了地下生物量的分配,而唐古特忍冬增加了地下生物量的分配。3)皆伐和恢复时间的增加改变了迹地物种组成,促使阳性乔、灌木在迹地上定居。4 个迹地上共出现了灌木15 种,乔木3 种,没有出现天然云杉和冷杉幼苗。随着恢复时间的增加,迹地上的灌木物种由原始林下的耐阴物种逐步发展为以针刺悬钩子(Rubus pungens)为主的阳性灌木。4)影响灌木幼苗密度和幼树密度的因子不一致。灌木幼苗密度与灌木层盖度显著负相关,与苔藓层盖度显著正相关。幼树密度与草本层盖度正相关,与苔藓层盖度、灌木层盖度和高度负相关。5)研究发现在青藏高原东缘山原区皆伐15~20 a 后,迹地仍以草本植物为主,推测皆伐后至少20 a 以上迹地才可能向灌丛阶段过渡,比高山峡谷地区的演替进程至少推迟了20 a。银露梅和唐古特忍冬在皆伐后自然恢复过程中表现出不同的生长与繁殖策略是由两个物种的生物学特性的差异引起的。银露梅比唐古特忍冬更适应迹地退化环境。促进青藏高原东缘山原林区迹地森林恢复一方面是尽量减少人为活动的破坏,另一方面,可以通过在迹地中播种适当的乡土乔、灌木种子(如白桦、银露梅)等人工措施,以加快演替进程。The succession pattern and process of plant community and their environments is a hot spotin community and ecosystem dynamic study. Four clearcuts were chosen in Rangtang(recovery time of 8 a、10 a、16 a and 21 a), which represented the key stage of thecommunity evolved from grass stage to shrub stage in the eastern margin of theQinghai-Tibetan Plateau. The growth and reproduction of the Potentilla glabra andLonicera tangutica and the natural regeneration of shrub plants in the primary Piceabalfouriana forest and 4 clearcuts were studied to explore how clear cutting andnatural recovery process affected the understory shrub species during the 21 years inthe eastern margin of the Qinghai-Tibetan Plateau. The main results were below.1) The growth and reproduction of P. glabra significantly increased after forestclear cutting.. But it was not so significant as to the L. tangutica. The organismbiomass and total biomass of P. glabra were increased obviously after clear cutting(P< 0.05). But only leaves and underground biomass of L. tangutica increasedsignificantly after clear cutting(P < 0.05). The number of fruit and growth of P. glabraincreased significantly after clear cutting too(P < 0.05). The ramet height, basaldiameter , organism biomass and friut number of P. glabra and L. tangutica reducedas the increase of recovery time.2) The biomass allocation patterns varied between P. glabra and L. tangutica inthe primary forest and clearcuts. The biomass allocation of P. glabra both in primary forest and clearcuts was followed as: underground part > stem > branch > leaves.However, the biomass allocation of L. tangutica had changed after the clear cutting.The biomass allocation of L. tangutica in the primary forest was followed as: stem >underground part > branch > leaves and it was underground part > stem > branch >leave in clearcuts. The biomass allocation of P. glabra and L. tangutica varied amongclearcuts. Aboveground biomass was increased while underground biomass decreasedfor P. glabra with the increase of recovery period. However, the L. tangutica showedthe reverse changing pattern.3) Clear cutting and recovery time had changed the species composition of theclearcuts. There were 15.shruby species and 3 tree species in the four clearcuts. Nospruce and fir seedlings were found. In the early stage after clear cutting, there wereonly understory shrub species from the primary Picea balfouriana forest. The sunnyspecies, especieally Rubus pungens invaded intensly as the increase of recovery time.4) There was a significant negative relationship between density of seedlingswith shrub layer coverage and positive correlation with moss coverage. The saplingshad significantly positive correlation with herb layer coverage and negativecorrelation with moss coverage, shrub layer coverage and height.5)Comparing to studies in Miyalou, a nearby high mountain and canyon area,the secondary sucession in this subalpine plateau areas lagged at least 20 years.P. glabra and L. tangutica showed different growth and reproduction strategies toclear cutting and natural recovery , which may associated with the difference of theirbiological characters. P. glabra was more adaptive to the clear cutting than the L.tangutica. Two suggestions were probably recommended to promote the recoveryprogress in the subalpine plateau areas based on the results of this study. Limitanthropogenic disturbance, and meanwhile sow native tree and shrub seeds inclearcuts.

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本文以形态特征为主,并参考其它证据,将中国Sect. Metapolystichum分为2个亚组,8个系,共记载45种2变种,其中新分类群21种1变种,新分布1种,新组合1个,并有11个新异名。对每种载有文献和标本引证及简要特征,新种则记有拉丁描述,并对某些疑难种进行了讨论。本文对叶表皮细胞的解剖研究表明,中国Sect.Metapolystichum植物气孔基本类型有两种,即十字型四细胞型和轴极型。各种植物的叶表皮细胞形态特征都不尽相同,有一定的分类学意义。作者对孢子形态的研究表明,中国Sect. Metapolystichum植物孢子周壁纹饰可分为八类,即波状、皱波状、条纹状、脑纹状、假网状、穴状、网状和复网状;在44种2变种中,孢子周壁纹饰表现出43种不同的形态。这一研究为分类上解决一些疑难问题、组下分类及系统发育研究提供了重要依据。本文中至少23种植物的孢子形态属首次报道。本文还根据中国Sect. Metapolystichum植物形态、解剖和孢子特征,遵循分支系统学的理论,借以确定了本组植物27个性状的极性;应用最大同步法(略有改进),通过简约性分析,构建了中国Sect. Metapolystichum植物有根的Wagnet树。作者对中国Sect. Metapolystichum植物的植物地理学特征也进行了分析,讨论了本组植物地理分布特征、间断分布现象、特有现象、替代现象、植物区系成分等,并就中国Sect. Metapolystichum植物区系进行了初步分区。

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土壤是人类赖以生存的自然环境和农业生产的重要资源,目前土壤受到干旱和盐胁迫的危害越来越严重。杨树具有适应性强、生长快和丰产等特性,本论文以青杨组杨树为模式植物,研究杨树对土壤干旱和盐胁迫的生态生理及蛋白质组学反应,研究成果可为我国干旱半干旱地区营造人工林、防止沙漠化提供理论依据,也为恢复与重建盐污染地区退化生态系统提供科学指导。主要研究结果如下: 1 青杨不同种对逐步干旱胁迫的响应差异 将来自喜马拉雅山东缘高海拔的康定杨和低海拔的青杨枝条扦插在温室中,用来检测它们对逐步干旱胁迫的响应。研究结果表明来自不同海拔的杨树对逐步干旱胁迫的适应性反应是不一样的。株高、叶片发育、叶片相对含水量、丙二醛、过氧化氢等指标的显著性变化在青杨中比在康定杨中来得早些,而且随着干旱胁迫程度的增加,这些参数的变化越来越明显,尤其是当青杨受到严重干旱胁迫的时候;而可溶性蛋白、可溶性糖、游离脯氨酸、抗氧化酶活力变化在康定杨中来得早一些。与青杨相比,在干旱胁迫下,康定杨仍能保持较好的植株生长和叶片发育;康定杨也能在逐步干旱条件下积累更多的可溶性蛋白、可溶性糖、游离脯氨酸及抗氧化酶活力,但是在丙二醛和过氧化氢含量方面增加的更少些。而且,我们的研究结果表明高海拔的康定杨有更强的耐干旱能力,杨树对干旱胁迫的适应能力与干旱发生的速度、强度、持续时间及两种杨树的海拔有关。 2 干旱胁迫下青杨不同种的蛋白质组学分析 来自青杨和康定杨雌株的枝条扦插在温室中,用来研究它们对干旱胁迫的蛋白质组学反应。采用TCA-丙酮/酚提取法提取总蛋白,并进行双向电泳分析。在每个处理的重复图像中都能检测到1,000 个以上的蛋白点。在青杨中有58 个蛋白在干旱处理后发生显著变化,其中22 个蛋白通过肽指纹图谱成功鉴定。康定杨中有69 个蛋白的表达量发生了显著变化,其中有25 个蛋白通过肽指纹图谱成功鉴定。这些被鉴定的蛋白主要参与了光合作用、氧化还原平衡、信号传导、能量代谢、蛋白质合成等过程。尽管被鉴定的蛋白只占叶片总蛋白的很少一部分,但这些被鉴定的干旱响应蛋白可能对维持植株内部平衡方面有重要作用。 3 青杨的盐胁迫响应 青杨植株分别用 0、50 和100 mM NaCl 溶液进行处理。叶片相对含水量、叶绿素a、b 含量、CO2 同化速率和气孔导度的降低表明叶绿体受到了盐胁迫的影响。过氧化氢、丙二醛含量及电导率的升高表明细胞受到了伤害。可溶性糖、游离脯氨酸含量及抗氧化酶含量的上升增加了植株耐盐胁迫的能力。在每个处理的重复图像中都能检测到1,000 个以上的蛋白点。其中有38 个盐响应蛋白被成功鉴定,有16 个蛋白(点4、10、11、14、15、21、24、26、27、28、33、34、35、36、37 和38)出现在盐胁迫的植株中;3 个蛋白(点10、11 和35)只出现在重度盐胁迫处理中;而1 个蛋白(点1)只出现在对照处理中。2 个蛋白(点1 和2)表达量下降,其余蛋白点表达量都增加。被鉴定的蛋白一部分参与了生理生化反应,而另一部分则在信号传导、蛋白质合成等方面有重要作用。盐胁迫下的生理生化变化及蛋白质组学的联合研究有利于青杨对盐胁迫的适应性分析。 Soil is the indispensable environment for human survival and important resource for agriculture development. Nowadays soil is threatened by drought stress and salt stress. Poplars (Populus spp.) possess some characters such as strong acclimilation, fast growth and great production of biomass. In this study, different species of Populus section Tacamahaca spach were used as model plants to investigate the ecophysiological and proteomic responses to drought stress and salt stress. Our results can provide theoretical evidence for the afforestation and prevention of desertification in the arid and semi-arid areas, and also can supply scientific direction for the reconstruction and rehalibitation of ecosystems contaminated by salinity. The results are as follows: 1 Adaptive responses to progressive drought stress in two contrasting poplar species originating from different altitudes Cuttings of Populus kangdingensis C. Wang et Tung and Populus cathayana Rehd., originating from high and low altitudes in the eastern Himalaya, respectively, were examined during one growing season in a greenhouse to determine the effects of progressive drought stress. The results manifested that the adaptive responses to progressive drought stress were different in these two species from different altitudes. Significant changes in height increment, leaf development, relative water content (RWC), malondialdehyde (MDA) and hydrogen peroxide (H2O2) appeared earlier in P. cathayana than in P. kangdingensis, whereas changes in soluble protein, soluble sugar, free proline and antioxidant enzymes appeared earlier in P. kangdingensis. In addition, changes in these parameters became more and more significant when the drought stress progressed, especially under severe drought stress in P. cathayana. Compared with P. cathayana, P. kangdingensis was able to maintain a superior height increase and leaf development under drought stress. Also, P. kangdingensis possessed greater increments in soluble protein, soluble sugar, free proline and antioxidant enzymes, but lower increments in MDA and H2O2 than did P. cathayana when the cuttings were exposed to progressive drought stress. Our results suggest that P. kangdingensis originating from the high altitude has a better drought tolerance than does P. cathayana originating from the low altitude. Furthermore, this study manifested that acclimation to drought stress are related the rapidity, severity, duration of the drought event and the altitude of two contrasting species. 2 Proteomic responses to drought stress in two contrasting poplar species originating from different altitudes The cuttings from a female clone of P. kangdingensis and P. cathayana were used to determine proteomic response to drought stress, respectively. Total proteins of the leaves were extracted by a combination of TCA-acetone and phenol, and separated by two-dimensional gel electrophoresis. More than 1,000 protein spots were reproducibly detected on each gel. 58 differentially expressed spots were detected under drought stress in P. cathayana and 22 drought-responsive proteins were identified by peptide mass fingerprint. 69 differentially expressed spots were detected under drought stress in P. kangdingensiss and 25 drought-responsive proteins were identified by peptide mass fingerprint. The identified proteins are involved in several processes, i.e., signal transduction, protein processing, redox homeostasis, CO2 fixation and energy metabolism. Although the proteins identified in this investigation represent only a very small part of the poplar leaf proteins, some of the novel drought-responsive proteins identified here may be involved in the establishment of homeostasis in response to drought stress in the woody plants. 3 Responses to salt stress in P. cathayana Cuttings from a female clone of P. cathayana were treated by Hoagland’s solution: 0, 50, 100 mM NaCl, respectively. Salinity significantly decreased the relative water content of leaves, the contents of chlorophyll a and chlorophyll b, CO2 assimilation rate (A) and stomatal conductance (gs) in both salt stress treatments,which suggested the chloroplast was affected by salt stress. The observed increases of H2O2 and malondialdehyde contents and electrolyte leakage suggested that salinity caused cellular damage, whereas the increases in compatible solutes and in the activities of antioxidant enzymes enhanced the salt tolerance. More than 1,000 protein spots were reproducibly detected on each gel, and 38 salt-responsive proteins were successfully identified by peptide mass fingerprint (PMF). 16 spots (spot 4, 10, 11, 14, 15, 21, 24, 26, 27, 28, 33, 34, 35, 36, 37 and 38) absent in the control sample were induced by the salt treatment, and three spots (spot 10,11 and 35) were present only in the severely salt-stressed treatment. The %vol of the differentially expressed proteins generally increased with progressing salt stress, except for the decreased %vol of two proteins (spot 1 and 2) under salt stress and the presence of spot 1 only in the control sample. Some of the novel salt-responsive proteins identified here may be involved in physiological, biochemical response to salt stress in P. cathayana, the other identified proteins play a role in numerous cellular functions, including signal transduction and protein processing. An integrated physiological, biochemical and proteomic approach was used here to systematically investigate salt acclimation in poplar.

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本研究通过我国CDBI、 KUN、PE、SZ等主要标本馆约3, 500份馆藏标本的研究和野外考察相结合,对我国蔷薇属(Rosa L.)芹叶组(Sect. pimpinellifoliae DC. ex Ser.)植物以及相关组的一些种进行了性状特征、形态和微形态的研究,对该组的一些种的形态特征描述进行了补充,同时给出详细的地理和海拔范围分布图。综合花粉以及种子(瘦果)形态的研究结果重新制订了分种检索表,同时,对该组一些形态相近容易混淆的种进行了对比研究,特别对一直存在争议的绢毛复合体(绢毛蔷薇R. sericea Lindl.和峨眉蔷薇R. omeiensis Rolfe)进行了大量宏观形态特征的研究,并用光学显微镜(LM)和扫描电镜(SEM)对二者的花粉及种子形态、微形态进行对比研究和分析,主要研究内容包括: 1. 芹叶组孢粉研究 对芹叶组的10个种及相关的4个组共17个种(18个样品)的植物花粉进行了光镜和扫描电镜观察和比较研究。研究结果表明:蔷薇属植物花粉粒大小为中等偏小,极轴长23.98[21.82(R. graciliflora Rehd. et Wils.)~29.18(R. tsinglingensis Pax. et Hoffm.)] μm,赤道轴长28.65[24.15(R. graciliflora)~34.70(R. davidii Crép.)] μm;花粉属辐射对称等极单花粉,花粉形态赤道面观呈球形到超长球形;极面观为三裂圆形或近圆形,三孔沟,孔缘加厚,具中部突起的桥状盖。花粉外壁纹饰为条纹状,光镜下形态特征相差不大;在电镜下外壁条纹和脊沟内穿孔的形状、大小和频度等特征,常具组至种水平上的可见变异,可作为组至种水平划分的依据。 根据花粉外壁条纹特征及穿孔形状和数目等特征,本研究将这些植物的花粉归为5个类型,并编制了分组检索表。同时,根据条纹状的清晰度,排列方式、条纹形状、穿孔大小及其频度等方面的差异,各有特点,对该组的10个种编制了分种检索表。 2. 芹叶组种子形态研究 应用光学显微镜和扫描电镜对我国蔷薇属芹叶组14个种及相关组5个组共36种植物的种子宏观形态及种皮微形态特征进行了观察研究。结果显示,蔷薇属种子形态多样,形状分别为肾形、卵形或锥形等;种子颜色以淡棕色、褐色以及土黄色为主;种子大小种间相差悬殊,相对体积为(长×宽×厚)36.66(4.79~114.47) mm3。光镜下,种子宏观形态特征具组内一致性,在扫描电镜下种子表面结构特征因种而异,其纹饰以网纹为主,可分为3种类型,即近平滑型、负网纹型和网纹型。研究结果表明,蔷薇属种子表面纹饰与地理分布关系不大,具有组及种内稳定性。其种子形态、大小、表而纹饰类型等特征可作为蔷薇属组及种水平上的分类依据。 结合蔷薇属花粉形态研究结果,得出蔷薇属种皮微形态特征与花粉外壁纹饰特征相吻合,在代表组及种的特征上具相关性的结论。同时根据种子形态、微形态结构特征的组间区别和种间差异编制了分组及芹叶组14个种的分种检索表。 3. 绢毛蔷薇复合体的研究 通过对大量标本的研究、野外观察以及扫描电镜对绢毛蔷薇复合体的花粉形态和种皮表面结构进行研究,通过对小叶、花粉及种子的形态定量分析结果支持Rowley (1959)的观点,将峨眉蔷薇处理为绢毛蔷薇的一个变种。 综上研究结果得出,蔷薇属植物的小叶片数目、花被基数以及花粉及种子形态等性状是较为稳定的,这些特征可很好的作为分类学依据。 The morphology, pollen exine sculpture and seed coat structure of the species of Rosa sect. Pimpinellifoliae and related sections were studied.About 3,500 herbarium specimens at CDBI, KUN, PE, and SZ were examined. Field work in Sichuan and Yunnan were conducted. Revisions of some species were carried out and a new key to species of sect. Pimpinellifoliae was proposed based on morphology, pollen exine sculpture and seed coat structure, Detailed morphological descriptions, geographical distributions and the altitudinal ranges of some taxa are given. The systematics of the species complex, the Rosa sericea complex (R. sericea Lindl. & R. omeiensis Rolfe), was emphasized. This thesis focused on the following three aspects: 1. Pollen morphology of Rosa sect. Pimpinellifoliae The pollen morphology of 18 samples representing 10 species of the Eurasian Rosa sect. Pimpinellifoliae and 7 additional species of related sections was investigated under LM and SEM. The pollen grains are monadic, actinomorphic, equipolar, medium-sized, spheroidal to perprolate in equatorial view, 3-lobed circular or semi-circular in polar view, crassimarginate, pontoperculate, and with striate exine sculpture. The striate sculpture varies among sections and species. The equatorial axis ranges from 17.97 μm (R. sikangensis) to 29.18 μm (R. tsinglingensis) with an average of 23.98 μm in length, while polar axis varies from 24.15 μm (R. gracilifolra) to 34.70 μm (R. davidii) with an average of 28.65 μm in length. The pollens can be divided into five types based on striate sculpture and a key to the sections sampled was proposed accordingly. The pollen morphology of species of sect. Pimpinellifoliae is more homogeneous and different from other sections sampled and did not support the two-series subdivisions in sect. Pimpinellifoliae. A key is also provided based on characers of pollen morphology among species in sect. Pimpinellifoliae. 2. Seed coat structure of Rosa sect. Pimpinellifoliae The seed coat structure of 39 samples representing 14 species of Rosa sect. Pimpinellifoliae and 12 additional species of related sections was investigated under LE and SEM. The seed relative volume (Length × width × thickness) ranges from 4.79 to 114.47 mm3 with an average of 36.66. mm3. The seeds are reniform, ovate or oblong in shape, with orange-brown, light brown or deep brown color. Seed coat sculpture was reticulate or striate-like reticulate. There was no difference in sculpture character of various speices under LM, while three types of seed coat sculpture were identified under SEM and a key to species based on the seed coat sculpture was provided. The three types of seed coat sculpture were nearly smooth, areolate and reticulate. The study of the seed coat sculpture of same species sampled from different populations showed that characters on the seed coat are stable, and thus the size, shape and seed coat sculpture can be used in species level identification. Interestingly, characters in the seed coat sculpture and the pollen morphology in sect. Pimpinellifoliae are consistent at in specific or sectional levels. A key to the 14 species sampled was given based on seed coat sculpture. 3. The study on Rosa sericea complex The Rosa sericea complex contains R. omeiensis and R. sericea. They are morphologically similar to one another and the systematic status of R. omeiensis has been controversial. In this study we examined large numbers of herbarium specimens of R. omeiensis and R. sericea and conducted field observations in the Hengduan Mts.. We also performed SEM study of pollen morphology and seed coat structure of R. omeiensis and R. sericea. We further carried out intensive morphometric study on the leaflet, pollen, and seed morphology. Our results showed that R. omeiensis should be sunk to be a variety of R. sericea, just as Rowley’s treatment in 1959. In conclusion, the features in the number of leaflet and petal, and the morphological character on pollen and seed are relatively stable. Therefore these characters are very useful in taxon delimition.

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全球气候变化已经成为不争的事实,其中全球变暖是近年来国内外的研究热点之一。土壤碳库作为陆地生态系统最大的碳库,气温升高必然会导致一系列的土壤碳储量和碳通量的变化,这些微小的变化又可能导致大气CO2浓度的变化并强化这种变暖的趋势。目前,土壤碳循环对温度升高的响应仍然是陆地碳循环研究最缺乏的部分,对土壤有机碳动态变化的研究仍存在着很大的不确定性与争议。四川西部的亚高山人工针叶林是青藏高原东部高寒林区的重要组成部分,是研究全球变化对森林生态系统影响的关键地区和重要森林类型。本研究通过采用原位人工模拟增温装置(Open-top chambers,OTCs)对川西米亚罗60年人工云杉林土壤实施增温,研究高海拔地区森林,尤其是人工森林系统下的土壤有机碳 含量、土壤呼吸及土壤酶活性对温度升高的响应。结果表明: 1. 增温处理的660天(2005年11月至2007年9月)期间,增温条件下的平均气温和土壤平均温度分别比对照提高0.43 ℃和0.27 ℃;0~10 cm土壤含水量在增温的不同时期均有不同程度的降低。 2. 土壤蔗糖酶、蛋白酶和脲酶活性在温度升高的不同阶段均有不同程度的提高。在增温处理300天(2006.09)、540天(2007.05)、600天(2007.07)和660天(2007.05)后,0~10 cm层的蔗糖酶活性分别比对照提高了36.36%(P<0.05)、24.31%、14.54%(P<0.05)和7.22%,脲酶活性分别提高了12.90%、24.19%(P<0.01)、34.48%(P<0.05)和14.64%(P<0.05),蛋白酶活性分别提高了31.37%、1.99%、3.70%和17.80%。10~20 cm层的土壤酶活性也均有不同程度的提高,但均没有显著差异。蔗糖酶、脲酶和蛋白酶活性均呈现出随土层加深而减弱的趋势。 3. 土壤过氧化氢酶和多酚氧化酶活性在增温的第1年内均有不同程度的提高,但在增温的第2年内比对照有所降低。增温300天后(2006.09),过氧化氢酶和多酚氧化酶在0~10 cm层分别比对照增加3.76%和49.25%(P<0.05),10~20 cm层分别增加了5.54%和29.67%。在增温的第2年内,增温540天(2007.05)、600天(2007.07)和660天(2007.09)后,0~10 cm层的过氧化氢酶活性分别比对照降低了27.70%(P<0.05)、4.34%和1.47%,多酚氧化酶活性分别降低了5.86%、11.76%(P<0.05)和7.47%。增温的第2年内,10~20 cm层的过氧化氢酶和多酚氧化酶活性也均有不同程度的降低,但差异均未达到显著水平。不同土层之间相比较,过氧化氢酶活性随土层加深而降低,多酚氧化酶活性随土层加深而增加。 4. 土壤有机碳和有机质在增温的不同阶段,含量比对照均有所降低;且随增温时间的延长,降低的幅度下降。0~10 cm层的土壤有机碳和土壤有机质在增温300天(2006.09)、540天(2007.05)、600天(2007.07)和660天(2007.09)后分别降低了8.69%、4.35%、3.80%和2.44%,差异均未达到显著水平。土壤全氮含量在增温后与对照相比无明显的增加或者降低趋势。增温条件下的土壤C/N比与对照相比有所降低,但在增温各阶段的差异均不显著。10~20 cm层的有机碳、有机质和C/N比也有不同程度的降低趋势,但差异均不显著。不同土层之间相比,0~10 cm层的有机碳、有机质、全氮含量和C/N比均高于10~20 cm层,呈现出随土层加深而降低的趋势。 5. 土壤呼吸速率在增温第1年内,与对照相比明显提高,但在增温处理2年后,与对照相比无显著变化。增温300天(2006.09)和360天(2006.11)后分别提高了13.32%和21.17%,差异显著。增温处理540天(2007.05)到660天(2007.09)期间,与对照相比,不仅没有明显的提升,反而有些月份比对照有所降低,对温度升高的敏感性降低,呈现出对温度升高的适应性。土壤呼吸的日呼吸速率呈现单峰曲线形式,在14:00~20:00期间达到最大值,在4:00~10:00期间具有最低值。土壤呼吸的季节变化,呈现出与外界环境温度相一致的趋势,在7月份(夏季) 最高,11月份(冬季)最低。土壤呼吸与2 cm土壤温度、5 cm土壤温度和空气温度均呈极显著指数相关,与0~10 cm土壤含水量呈线性相关,相关性达到显著水平,但低于土壤呼吸与温度的相关性。 The past century has seen a marked increase in atmospheric carbon dioxide concentrations and a concomitant warming that has drawn scientific attention to the link between global carbon stocks and climate change. In particular, the decomposition and turnover of soil organic matter is recognised as an important determinant of carbon driven climate change. The slightly variation in soil organic carbon will result in the increase of atmospheric carbon dioxide concentrations and reinforce the tendency of warming. The experiment was conducted in Subalpine coniferous forest in western Sichuan province. Subalpine coniferous forest in western Sichuan was a important part of eastern Qinghai-Tibetan Plateau, which play a important role in reseaching the sensitivity of forest ecosystem to climate change. To investigate the effects of elevated temperature on soil organic carbon content, soil respiration rates, and soil enzyme activities in subalpine Picea asperata plantations, a esimulated warming measure was applied with Open-top chambers. The results were as followed: 1) During the period from Nov. 2005 to Sep. 2007, mean air temperature and soil temperature were respectively 0.43℃ and 0.27℃ the ambient higher. Soil water content decreased to different exent in different months in warmed plots than in unwarned plots at depth of 0-10 cm. 2) In general, elevated temperature enhanced the soil enzyme activities of invertase, protease, and urease. In the first year of warming—after 300 days’ treatment (in Sep,2006), the activities of invertase, protease, and urease increased by 36.36%, 12.90% and 31.37% respectively at the depths of 0-10 cm,among which the activity of invertase reached statistic significance. In the second year of warming, invertase activity increased by 24.31% after 540 days’ treament (in May, 2007), 14.54% after 600 days’ treament (in Jul, 2007) and 7.22% after 660 days’ treatment (in Sep, 2007) at the depths of 0-10 cm, and the differences in July and Septemmber were statistically significant. Elveated temperature also increased the activity of urease in the second year of warming and had significant effects in May and July. The activity of protease in warmed plots was also higher than in unwarmed plots at depths of 0-10 cm, but there was no significant difference. Elevated temperature had no significant effects on all soil enzyme acitivities at the depths of 10-20 cm in the first and sencond year. The values of above-mentioned soil enzyme all decreased with soil layers. 3) Eleavted temperature enhanced the activities of catalase and polyphenol oxidase in the first year of warming while they turned out downtrend in the second year. The activity of catalase increased by 3.76% and 5.54% at depths of 0-10 cm and 10-20 cm respectively in the first year—after 300 days’ warming (in Sep, 2006), the differences of which had no statistical significance. The activity of polyphenol oxidase was significantly increased by 49.25% at depths of 0-10 cm and not significantly increased by 29.67% at depths of 10-20 cm after 300 days’ warming. In the second year of warming, the catalase activity was significantly decreased by 27.70% after 540 days’ treament (in May, 2007) and not significantly decreased by 4.34% and 1.47% after 600 days’ (in Jul, 2007) and 660 days’ treament (in Sep, 2007) respectively. The activities of catalase and polyphenol oxidase at depths of 10-20 cm were decreased to different extent, but there was no significant difference. Catalase activity stepped down with soil layers while polyphenol oxidase activity stepped up. 4) Increased temperature in both the first year and the second year resulted tendency of decrease in the contents of soil organic carbon and soil organic matter, and C/N ratios at soil depths of 0-10 cm and 10-20 cm. However, with the prolonged warming, the tendency of decrease gradually tapered off and the extent of decrease in the second year of experiment were lower than that in the first year. The contents of soil organic carbon and soil organic matter were all decreased 8.69% by warming in the first year and dcreased 4.35%, 3.80% and 2.44% in May, July and September of the second year, but no significant difference were found. The C/N ratios increased 8.52% in the first year of warming and had less increment in the second year, all of which were not statistical significant. Eleveated temperature had no obvious effect on the content of tatol N in two year consecutive warming experiment. The contents of soil organic carbon and soil organic matter, total N and C/N ratios all had the tendency of dcreasing with soil layers. 5) Soil respiration rates were significantly enhanced by 13.32% and 21.17% after 300 days’ (in Sep, 2006) and 360 days’ (in Nov, 2006) treament in the first year of warming, but the same showed no obvious difference in the second year of treatment, which was assumed the adaptability of soil respiration with a certain heightened temperature. Diurnal soil resspiration showed a daily variation with a minimum value between 4:00 and 10:00 h and a maximum value between 14:00 and 20:00 h, coinciding with the minimum and maximum values of soil temperature at 2 cm. Soil respiration rates exhibited a pronounced seasonal variation with minimum values in Novmber and a maximum value in July, approximately coinciding with the seasonal variation of air and soil temperature. An exponential function provided the best fit for soil respiration with temperature while a quadric equation was used to estimate the effect of soil moisture on soil respiration, which were all significantly correlated. Soil respiraion rate was more highly correlated with the soil temperature than soil moisture.

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通过趾骨切片可以准确鉴定年龄,了解一个物种的最长寿命,也为我们研究确定一个物种的生长特点、性成熟期,以及一个地区一个物种的年龄结构、种群生态(Marnell,1998)和群落生态提供重要信息(Morrison,et a1.,2004)。 本论文使用骨骼鉴龄法对中国浙江省宁波市北仑瑞岩寺林场的镇海棘螈(Echinotriton chinhaiensis)雌性繁群进行了年龄结构研究。结果显示:第一次参加繁殖的年龄为3龄;繁群中数量占优势的是5龄、6龄。而在6龄以后参加繁殖的雌性个体数便开始随着年龄的增大而逐渐减少。参加繁殖的雌性年龄最大个体为8龄。平均年龄为5.13龄。同时对其年龄和头体长、体全长的相关性检验,发现其年龄与头体长和体全长不相关,镇海棘螈雌性的生长方式表现为性成熟后能量主要用于繁殖。 另外,对李子坪大凉疣螈(Tylototriton taliangensis) 雄性繁群进行了年龄结构研究。结果显示:大凉疣螈雄性第一次参加繁殖的年龄为4龄;繁群中数量占优势的是5龄、6龄、7龄。而在7龄以后参加繁殖的雄性个体数便开始随着年龄的增大而逐渐减少。参加繁殖的雄性中年龄最大的个体为10龄。平均年龄为6.7龄。对其年龄和头体长、体全长的相关性检验,发现其年龄与头体长和体全长不相关,大凉疣螈雄性生长特点也表现为性成熟后生长缓慢的特点。 研究材料方面,本文采用野外采样与标本馆标本相结合的方式获得了中国蝾螈科2个重要保护物种繁殖群体的剪(指)趾材料,使得建立于其上的年龄结构工作更加可靠、更加具有代表性。 此外,本论文讨论了镇海棘螈瑞岩寺种群繁殖总量年度间的差异及其产生原因。将1998、1999、2000、2008、2009年镇海棘螈(Echinotriton chinhaiensis) 瑞岩寺种群的繁殖量进行比较,发现虽然雌性平均窝卵数比较稳定,但繁殖总量小于1998、1999、2000年任何一年总产卵量的50%。对2008年镇海棘螈繁殖量大幅下降的原因分析发现, 2007年9、10月影响严重台风的两次强台风、瑞岩寺景区开发等因素可能是造成近年该种群繁殖量大幅下降的原因。而2008年初50年不遇的低温是否影响镇海棘螈的繁殖值得进一步追踪研究。2009年繁殖量较2008年没有明显的增长,可能是由于2007年的台风影响了其繁殖营养的积累。台风的影响可能存在滞后现象,对此有待进一步监测证明。 本研究首次对中国蝾螈科物种进行的年龄结构鉴定,为进一步了解中国蝾螈科动物的种群生态打下了坚实的基础。 Using skeletochronology, we can know the life span of a species, age of reaching sexual mature, and of course age structure, which are vital(Morrison,et a1.,2004). Skeletochronology was performed on Echinotriton chinhaiensis Ruiyansi female population. The result shows that: The oldest individuals were 8 years old and the youngest ones were 3 years old. Individuals of age class 5(39.13%) and 6(21.74%) were most numerous. The number of individuals participated in reproduction decreased with the increase of age after the sixth year. Average age is 5.13 years. There is no correlation between age and body size (SVL and TL). For female chinhai salamander, energy is devoted to reproduction after reaching sexual maturation. While using skeletochronology to study Tylototriton taliangensis Liziping male population, the oldest individuals is 10 years old, and the youngest ones is 4 years old. Individuals of the age class 5, 6, and 7 dominat this population. The number of individuals decrease with the increase of age also after the seventh year. Average age is 6.7 years old in this population. there is also no correlation between age and body size (SVL and TL).It turned out that T. taliangensis tend to grow slowly after reaching sexual maturation. In this thesis, specimens from both wild and museum were used to gain enough toe clipping samples. A big sample size guarantees the reliability of this study. In the meantime, E. chinhaiensis’s annual reproduction of the year 1998, 1999, 2000 ,2008,and 2009 was compared. The result shows there is a huge decline in E. chinhaiensis’s annual reproduction in 2008,even the egg clutch is very stable. After analyzing, it turned out the huge decline in 2008 was probably caused by typhoon in 2007, besides the effect of tourism development and cash crop planting. While the impact of extreme weather of 2008 on reproduction needs further investigation. In the year 2009, there is no obvious increase in annual reproduction. It maybe due to lasting impact of typhoon in 2007. It is the first age-structure study on these two Chinese salamanders. A solid foundation was laid for further population ecology study of these two species.

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从空间、时间、食物3个方面研究了若尔盖湿地3种两栖类的种间竞争,运用生态位理论探讨了3种两栖类利用环境资源的能力以及它们之间的共存模式,研究了3种两栖类年周期食性,并考察了畜牧业对3种两栖类食性及食物竞争格局的影响;此外,还通过实验室研究对2种两栖类幼体的种间竞争策略进行了考察。主要结果如下: 1、两栖类的空间资源利用状况:在3种两栖类成体生态位宽度的比较中,岷山蟾蜍(Bufo minshanicus)成体在牧场性质(0.41)、牛粪数量(0.42)、植被盖度(0.20)、地表温度(0.50)、地表湿度(0.51) 5个维度上的生态位宽度最窄;而倭蛙(Nanorana pleskei)成体在牛粪数量(0.81)、植被高度(0.63)、植被盖度(0.47)、小水体距离(0.68) 4个维度上的生态位宽度最宽。在3种两栖类亚成体生态位宽度的比较中,岷山蟾蜍亚成体在牧场性质(0.66)、牛粪数量(0.58)、植被高度(0.64)、小水体距离(0.51)、地表湿度(0.79) 5个维度的上生态位宽度最宽;倭蛙亚成体在牧场性质(0.39)、牛粪数量(0.30)、地表温度(0.18)、地表湿度(0.33) 4个维度上的生态位宽度最窄。高原林蛙(Rana kukunoris)在地表温度(成体:0.62;亚成体:0.56)、地表湿度(成体:0.84;亚成体:0.60)两个维度上具有较大的生态位宽度值,而在小水体距离维度上(成体:0.27;亚成体:0.14)的生态位宽度值则很小。比较3种无尾两栖类在不同生长阶段(成体、亚成体)的生态位宽度,发现高原林蛙和倭蛙的亚成体对栖息环境的要求更高。3种两栖类空间资源利用的相似程度很高,高原林蛙与倭蛙之间的生态重叠度(0.87)较之它与岷山蟾蜍(0.81)的生态位重叠度更大。 2、两栖类的日活动节律:高原林蛙成体、亚成体、岷山蟾蜍亚成体活动的最低气温为0℃、2℃、8℃;岷山蟾蜍和高原林蛙亚成体出现的数量与气温成极显著的正相关(r=0.797, p<0.001;r=0.794, p<0.001),高原林蛙成体出现的数量与气温有一定相关性(r=0.456, p<0.05);晴天时两栖类的活动性明显高于阴天(p<0.001);多云转晴天气,高原林蛙和岷山蟾蜍亚成体出现两次日活动高峰,分别为中午12:30左右和下午15:30~16:30之间;多云天气,高原林蛙和岷山蟾蜍亚成体出现两次日活动高峰,分别为9:30~10:30之间和15:30~16:30之间。 3、两栖类的食物资源利用状况:春、秋两季,高原林蛙最主要的食物是蜉金龟科(Aphodiidae)昆虫,相对重要性指数(IRI)最高(春季:35.28%,秋季:28.57%),其次为昆虫的幼虫,以及双翅目的毛蚊科(Bibionidae)、蝇科(Muscidae)、丽蝇科(Calliphoridae)昆虫,秋季,蝗虫是高原林蛙食物组成中的重要部分;岷山蟾蜍最主要的食物是蚂蚁(IRI,春季:85.54%,秋季:49.70%),其次为蜉金龟科、象甲科(Curculionidae)、步甲科(Carabidae)、粪金龟科(Geotrupidae) 等鞘翅目昆虫;倭蛙春季的最主要食物也是蜉金龟科昆虫(IRI,春季:13.41%),其次为蚂蚁、毛蚊科昆虫、昆虫的幼虫以及狼蛛科(Lycosidae)。3种两栖类中,倭蛙的食性生态位宽度相对较宽(0.43),而岷山蟾蜍(0.09)和高原林蛙(0.22)的生态位宽度较窄,与春季相比,两栖类在秋季的食谱更宽。以利用食物种类为标准,春季高原林蛙与倭蛙的生态位重叠度(0.40)比它与岷山蟾蜍的生态位重叠度(0.33)更大。 4、畜牧业对两栖类食性及食物竞争格局的影响:以藏牦牛粪为食物或寄居场所的昆虫,如蜉金龟科、粪金龟科、毛蚊科、蝇科、丽蝇科昆虫和某些昆虫幼虫,是3种两栖类食物谱中最主要的组成部分,蜉金龟科昆虫在高原林蛙食谱中的比例更高,高原林蛙可能从畜牧业发展中获得更多的好处,使之在食物竞争方面处于优势地位。与无放牧样地相比,在有放牧样地的中,两栖类食谱中的蜉金龟科昆虫数量更多(有放牧:31.94%;无放牧:21.32%)、出现频率更高(有放牧:76.38%;无放牧:44%)。然而在不同样地上(有放牧/无放牧),两栖类的食物组成无显著性差异(P=0.188),两栖类的数量(P=0.075)、肥满度(P=0.537)均没有显著差别。 5、两栖类幼体的竞争策略:实验室条件下,通过活动性水平,变态时的体重、增长率和完成变态所需时间考察自然条件下常同水塘分布的中华蟾蜍(Bufo gargarizans)和高原林蛙蝌蚪的竞争策略。结果表明:中华蟾蜍蝌蚪在不同食物资源条件下,所选择的生存策略可能不同,即食物资源充足时,增加活动性获取更多食物,食物资源有限时,降低活动性且提前完成变态;与中华蟾蜍蝌蚪相比,在食物资源有限时高原林蛙蝌蚪获取食物能力可能更强。 This paper presented the study of competition of three amphibians (Rana kukunoris, Nanorana pleskei, Bufo minshanicus) based on spatial, temporal and dietary scales in Zoige wetland. We measured coexistence patterns of three amphibians and analyzed their ability of exploiting resource. Effects of grazing on the diet composition and diet competition of amphibians were analyzed by their diet composition during spring and autumn. Furthermore, we examined the competitive ability of larval common frogs (Rana kukunoris)and common toads(Bufo gargarizans) in a laboratory experiment, and analyzed their competitive strategies respectively. The results were as follows: 1 .The status of using spatial resource Niche breadths of B. minshanicus adults on 5 dimensional axes including character of pasture(0.41), number of yaks dung(0.42), vegetation coverage(0.20), temperature (0.50)and humidity(0.51) of ground surface were narrower than adults of R. kukunoris and N. pleskei. Niche breadths of B. minshanicus subadults were broader than R.kukunoris subadults and N.pleskei subadults on 5 dimensional axes including character of pasture (0.66), number of yaks dung (0.58), vegetation height (0.64), distance to small waterbodies (0.51), humidity of ground surface (0.79). Niche breadths of N. pleskei subadults were the narrowest in three anurans subadults on 4 dimensional axes including character of pasture (0.39), number of yaks dung (0.30), temperature (0.18) and humidity (0.33) of ground surface, niche breadths of N. pleskei adults were the broadest in three anurans adults on 4 dimensional axes including number of yaks dung (0.81), vegetation height (0.63) and coverage(0.47), distance to small waterbodies(0.68).Comparatively, niche breadths of R. kukunoris were broader on the two microclimate factors including temperature(adults:0.62;subadults:0.56) and humidity (adults:0.84;subadults:0.60)of ground surface, but was narrow on distance to small waterbodies(adults:0.27;subadults:0.14). Strategies for using habitat resource of adults and subadults of the three species anuran were different. Generally, subadults of R. kukunoris and N. pleskei needs better habitat condition. It was quite similar that three anurans exploited spatial resource, Niche overlap between R. kukunoris and N. pleskei (0.87) was greater than that between R. kukunoris and B.minshanicus(0.81). 2.Daily activity rhythm R. kukunoris audlts were active when air temperatures were as low as 0℃, R. kukunoris subadults were active at 2℃, B.minshanicus subaudlts were active at 8℃. Positive correlation was found between activities of amphibians and air temperature, Subadults of R.kukunoris, (r=0.797, p<0.001), Subadults,of,B.minshanicus, (r=0.794, p<0.001), andbadults,of,R.kukunoris(r=0.456, p<0.05).Amphibians were more active during sunny days than cloudy days. In cloudy turning into sunny, R. kukunoris and B.minshanicus subadults had two active peak: at noon about 12:30 and 15:30~16:30 pm; in cloudy, R. kukunoris and B.minshanicus subadult had two active peak too : 9:30~10:30am,15:30~16:30pm. 3.Diet analysis Aphodiidae was the most commonly consumed food item by R. kukunoris based on index of relative importance (IRI) during spring (35.28%) and autumn (28.57%) in Zogie wetland. Besides Aphodiidae, larval insect, dipterans such as Bibionidae, Muscidae, Calliphoridae also were important food item for R. kukunoris, in autumn, locust was one of important food item for R. kukunoris. The most important food item for B.minshanicus during spring (IRI:85.54%) and autumn (IRI:49.70%) was ants, following, was coleopterans, such as Aphodiidae, dung beetle. Aphodiidae (IRI:13.41%) were the most important consumed food item by N. pleskei during spring too, following, was ants and Bibionidae. Dietary breadth of N. pleskei (0.43) were greater than R. kukunoris (0.22) and B. minshanicus (0.09). As a whole, Dietary breadth of amphibians during aurumn were greater than spring. Based on prey item, dietary overlap between R. kukunoris and N. pleskei (0.40) was greater than that between R. kukunoris and B.minshanicus (0.33) during spring. 4.Effects of grazing on the diet composition and diet competition of amphibians Amphibians are an important part of the pasture ecosystems as prey and predator. In Zogie wetland, major diet of amphibians was closely associated with dung of yaks, for example, Aphodiidae, Bibionidae, Muscidae, dung beetle. Dung of yaks was major diet and habitat of these insects. Proportion of Aphodiidae was higher in diet composition of R. kukunoris than N. pleskei and B.minshanicus, with development of pasturage, R. kukunoris may have a diet competitive advantage over N. pleskei and B.minshanicus. Number of Aphodiidae in diet composition of amphibians was higher in samples with grazing (31.94%) than in those without grazing (21.32%). Occurrence Frequency of Aphodiidae in diet composition of amphibians was higher in samples with grazing (76.38%) than in those without grazing (44%). However, There was not significantly different on diet composition (P=0.188), and number (P=0.075) and the relative fatness (P=0.537) of amphibians between grazing samples and without grazing. 5.Competitive strategies of amphibian larvae I examined the competitive ability of larval toads (Bufo gargarizans) and frogs (Rana kukunoris) which co-occur in the nature pond by activity level, the growth rate and mass at metamorphosis and larval period in a laboratory experiment. The results suggest: In laborary, B.gargarizans adapted himself to different food level by changing activity. At high food level, B. gargarizans increased activity to gain more diet. At low food level, B. gargarizans decreased activity and achieved early metamorphosis. When food resource was limit, R. kukunoris could gain more food than B. gargarizans.

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采用微波消解、电感耦合高频等离子体原子发射光谱(ICP-AES)的方法,对62份不同小麦品种(系)中锌、铁、铜、钙、钠和钾的含量进行了测定。同时利用红外线品质测定仪对主要品质指标粗蛋白、湿面筋、沉降值进行了测定。结果表明,不同小麦品种(系)中各种矿质元素的含量存在差异,2006年小麦品种中铁含量变幅为18.55-58.19 ug/g,平均为30.83ug/g ,最高与最低的相差39.64ug/g;锌含量变幅为5.70-25.80 ug/g,平均为15.13ug/g ,最高与最低相差20.10ug/g。2008年小麦品种(系)中铁含量变幅为16.68-52.25 ug/g,平均为30.10ug/g,最高与最低相差35.58ug/g;锌含量变幅为12.29-33.47 ug/g,平均为21.11ug/g,最高与最低相差21.18ug/g;钙含量变幅为167.53-348.80ug/g,平均为248.59ug/g,最高与最低相差192.59ug/g;铜含量变幅为2.32-5.83 ug/g,平均为2.98ug/g,最高与最低的相差3.61ug/g;钾含量变幅为1822.71-4414.91 ug/g,平均为2617.87ug/g,最高与最低的相差2634.72ug/g;钠含量变幅为10.25-39.82 ug/g,平均为23.05ug/g,最高与最低的相差29.57ug/g。 两年不同小麦品种(系)中矿质元素的含量分析结果表明:铁、铜、钙、钠和钾含量年际变化不明显,说明小麦对铁、铜、钙、钠和钾的吸收较稳定;锌含量变化较大,可能受环境的影响比较大。分析各矿质元素含量与粗蛋白、湿面筋、沉降值及元素之间的相关关系,结果表明,锌含量与粗蛋白含量呈极显著正相关关系,相关系数为0.317,与湿面筋含量之间呈显著正相关,相关系数达到0.246;铁含量与粗蛋白含量呈显著的正相关关系,相关系数是0.262;铜、钙、钠和钾含量与粗蛋白含量、湿面筋和沉降值之间存在正相关,但不显著,其中钠与沉降值之间为负相关。表明施锌或铁对提高小麦粗蛋白和湿面筋有显著效应,其余矿质元素有促进作用但不明显。 利用RAPD分子标记技术对川育23、41058、川育20及其父母本进行分析,力图从分子水平找到小麦矿质元素含量之间的差异性,琼脂糖电泳结果表明不同的小麦品种(系)间扩增出了差异条带。 以上研究结果,将对筛选“微量营养强化型”小麦新材料,选育“微量营养强化型”小麦新品种奠定基础。 62 different wheat cultivars was digested with HNO3 in a tightly closed vessel heated under micro-wave,then contents of zinc,iron,copper,calcium,sodium and potassium were determined by inductively coupled plasma-atomic emission spectroscopy(ICP-AES).The main indexes of wheat quality such as total protein、wet glu and sedimentation volume were detected by Infratec 1255 Food & Feed Analyzer at the same time.The obtained results showed that variation for all of the mineral elements concentrations among different cultivars were observed .In 2006, the amplitude variation of the iron content was 18.55-58.19 ug/g,the average value was 30.83ug/g,and 39.64ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the zinc content was 5.70-25.8 ug/g,the average value was 15.13ug/g,and 20.10ug/g between the highest-content cultivar and the lowest one.In 2008, the amplitude variation of the iron content was 16.68-52.25 ug/g,the average value was 30.10ug/g,and 35.58ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the zinc content was 12.29-33.47 ug/g,the average value was 21.11ug/g,and 21.18ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the calcium content was 167.53-348.80ug/g,the average value was 248.59ug/g,and 192.59ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the copper content was 2.32-5.83 ug/g,the average value was 2.98ug/g,and 3.61ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the potassium content was 1822.71-4414.91 ug/g,the average value was 2617.87ug/g,and 2634.72ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the sodium content was 10.25-39.82 ug/g,the average value was 23.05ug/g,and 29.57ug/g between the highest-content cultivar and the lowest one. Analysis was made on the annual variation of mineral elements content in different Wheat cultivars ,the result shows:there is no obvious difference of iron ,copper ,sodium、calcium and potassium concentrations in wheat cultivars, suggesting the absorption of the iron, copper, sodium、calcium and potassium by wheat are relatively steady ,but zinc concentrations change obviously ,maybe influenced heavily by environment . The correlation between mineral elements 、mineral elements and total protein、mineral elements and sedimentation volume as well as mineral elements and wet glut were analysed in this paper, the result showed that there was significant positive correlation between zinc content and total protein (the correlation coefficient is 0.317), positive correlation between zinc content and wet glu (the correlation coefficient is 0.246), positive correlation between iron content and total protein (the correlation coefficient is 0.262). there was positive but not obvious correlation between the contents of copper, calcium, sodium or potassium and total protein, wet glut or sedimentation volume,among which was negative correlation between sodium and sedimentation volume.It was indicated zinc or iron fertilization has prominent effects in improving the total protein in wheat, the rest mineral elements have Non- obvious facilitation. The study then forecasted the genetic difference of different wheat by the molecular marker of RAPD in order to find differences in molecular level. Chuanyu23、41058、chuanyu20 as well as their male and female parents were analysed by RAPD markers,Agarose gel electrophoresis of DNA revealed the appearance of differential bands . The above-mentioned results of this study establish the foundation to screening the new materials of wheat of " strengthening type of micro- nutrition ", and to breeding the new wheat cultivars of" strengthening type of micro- nutrition ".

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本研究对自育小麦白粉病抗源“07鉴126”和条锈病抗源CD1437、CD0534-5进行抗性遗传分析和微卫星引物的筛选,建立了与PmCD1和YrCD抗病基因连锁的SSR分子标记,主要研究结果如下: 1.小麦白粉抗源“07鉴126”抗白粉病基因的鉴定和分子标记的建立 品系“07鉴126”对我国目前白粉菌强优势生理小种E09、E11和其它多种小种表现免疫或高度抵抗。Pm-sus是07鉴126的自然突变感病株。利用“07鉴126”和Pm-sus的F2抗病性分离群体进行抗条锈病性遗传分析和分子标记定位,结果表明,“07鉴126”的白粉抗性为显性单基因控制的全生育期抗性,暂命名为PmCD1;并筛选到了与PmCD1共分离的显性SSR分子标记Xbarc183。系谱分析和分子标记分析表明PmCD1来源于荆州黑麦。抗谱分析表明PmCD1不同于已知的黑麦抗白粉基因,是一个新的抗白粉病基因。Xbarc183这一分子标记的建立为PmCD1的分子标记辅助选择和抗病基因累加提供了方便。 2.小麦条锈抗源CD1437抗条锈病基因的鉴定和分子标记的建立 利用对优势条锈菌小种条中32免疫的小麦品系CD1437及其自然突变感病株Yr-sus杂交构建F2、F3抗病性分离群体。抗条锈病性遗传分析结果显示,1437的抗条锈性为显性单基因控制的全生育期抗性,该基因暂命名为YrCD。SSR分析发现,位于1B染色体上的7个SSR标记Xcfd65、Xgwm11、Xgwm18、Xbarc187、Xwmc406、 Xwmc419、Xwmc216依次分布在YrCD的一侧,与YrCD的遗传距离在1.7 cM至9.2 cM。YrCD和YrCH42的等位性分析显示二者可能为等位基因。YrCD和Yr24、Yr26的抗谱相似。系谱分析和分子标记分析表明贵农20是YrCD的供体。本研究推测YrCD、Yr24、Yr26和YrCH42可能是等位基因,并推测Yr-sus是缺失突变体。 3. 小麦条锈抗源CD0534-5抗条锈病基因的鉴定 利用对条中32免疫的小麦抗条锈病品系CD0534-5及其感病重组自交系CD0534-4建立F2抗病性分离群体。抗条锈病性遗传分析表明,CD0534-5的条锈抗性由两对独立的显性主效基因控制。用BSK法分析,发现其中一对基因与SSR分子标记Xgwm11、Xgwm18、Xwmc128、Xwmc419连锁,该基因是来源于贵农20的YrCD。另一抗性基因来源贵农19,是极有利用价值的未知抗性基因。 This study focused on the investigation and identification of a novel powdery mildew resistant gene PmCD1 in wheat lines 07jian126 and stripe rust resistant gene YrCD in wheat lines CD1482 and CD0534-5, and screened SSR markers tightly linked to them. The main results were as follows: 1.Identification and SSR markers screening of a novel powdery mildew PmCD1 in wheat line 07jian126. Using a Pm resistant wheat line 07jian126 and its Pm susceptible mutant, a F2 population was constructed. Pedigree and genetic analyses indicated that the Pm resistance in 07jian126 was tranderred from rye (Secale cereale L.) cv. Jinzhou and was controlled by a single dominant gene. Differential test using 21 Bgt isolates revealed that the Pm resistant gene in 07jian126 is novel and was temporarily designated as PmCD1. A dominant SSR marker Xbarc183/130 bp was found co-segregated with PmCD1 in the F2 population. The diagnostic band of Xbarc183/130 bp co-segregating with PmCD1 could be used as an ideal marker in marker-assisted-selection during wheat breeding program. 2. Identification and SSR markers mapping of yellow rust resistant gene YrCD in wheat line CD1437. Wheat line CD1437 was highly resistant to predominant Chinese stripe rust race CYR32 at both seedling and adult stages. A F2 population was developed from the cross of CD1437 and its Yr susceptible mutant Yr-sus. Genetic analysis indicated line CD1437 contains a single dominant gene, temporarily designated YrCD. Seven SSR markers on the chromosome 1BS including Xcfd65, Xgwm11, Xgwm18, Xbarc187, wmc406, Xwmc419and Xwmc216 were close linked to YrCD with a genetic dsitance 1.7 cM to 9.2 cM. YrCD came from wheat cultivar Guinong 20. Allelic test of CD1437 and Chinese cultivar Chuanmai 42 indicated that YrCD and YrCH42 were allelic. Reaction patterns of YrCD and Yr24, Yr26 to 21 PST isolates were the same. These results suggested that YrCD and Yr24, Yr26, YrCH42 might be allelic. 3.Detection and identification of yellow rust resistance genes in wheat line CD0534-5 Wheat line CD0534-5 was highly resistant to predominant Chinese stripe rust race CYR32, while its recombinant inbred line CD0534-4 was susceptible. Genetic analysis with a F2 population developed from the cross of CD0534-5 and CD0534-4 indicated line CD0534-5 contains two independent dominant genes. Four SSR markers on the chromosome 1BS including Xgwm11, Xgwm18, Xwmc128, Xwmc419 were found to linked with one gene in CD0534-5. According the locations of makers and pedigree, this gene in CD0534-5 was YrCD, from cultivar Guinong 20. Another resistant gene was from cultivar Guinong 19, different with those genes on 1B such as Yr10, Yr15, Yr5 etc, was a valuable resistant gene in wheat breeding.

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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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水稻是重要的粮食作物,其产量的增加和品质的改良都是关系国计民生的大事。就我国现阶段的国情而言,水稻产量在现有水平上稳步提升仍是未来十几年甚至几十年农业生产最重要的目标之一。尽管根据“超级杂交水稻育种”的战略设想和水稻育种实践,通过不断地改进育种技术可望在更高的产量水平上进行水稻杂种优势利用,在稻属植物内还具有很大的产量潜力可以挖掘。然而,仅仅从现有的种质基础出发,要更大幅度提高水稻单产,实现“超级杂交稻”的目标也存在一些困难:现有的推广品种是二倍体,尽管种类众多,但是其基因组的来源相对单一;同时,水稻基因组DNA含量也是作物中最少的,基因组内寻求开发潜力有一定困难;水稻作为C3植物,光合利用效率不高也是制约水稻产量提高的因素之一。因此,寻求常规手段以外的技术突破或者方法创新,是实现“超级杂交稻”的目标的迫切需求。本研究利用秋水仙素能抑制细胞分裂中纺锤丝的收缩、使细胞染色体加倍的作用,对水稻幼穗诱导的愈伤组织细胞进行加倍,并分化出再生植株;创制出水稻同源四倍体新的种质材料,在此基础上选育水稻同源四倍体雄性不育三系材料,并实现水稻同源四倍体的三系配套,开展水稻同源四倍体杂种优势利用和四倍体杂交水稻选育研究,建立水稻同源四倍体杂种优势利用的新技术体系。这不仅有助于倍性水平杂种优势的开拓和利用,同时也将为我国新世纪“超级稻”育种研究开辟一条新的技术途径。 水稻幼穗诱导愈伤组织并分化成苗是一项成熟、简单的组织培养技术。本研究以普通二倍体水稻亲本为材料,用秋水仙素进行水稻的多倍体化诱导,创制同源四倍体水稻三系亲本材料并对其进行鉴定。多倍体化以秋水仙素诱导的愈伤组织培养为基础,研究不同秋水仙素浓度梯度和愈伤组织诱导培养基组合对诱导四倍体植株的影响。结果表明在MS+2,4 D 1.0mg/L+ KT0.2mg/L+ IAA0.2mg/L 和500mg/L的秋水仙素处理下,水稻愈伤组织染色体加倍(有最高的效率)效果较好,平均加倍频率可达25.26%,其中,材料CDR22和IR26诱导较易成功,加倍频率分别达到75%和26.5%;相对材料94109 1.3%加倍频率和冈46B 10.8%加倍频率,诱导率差异极显著。 对水稻四倍体材料进行了形态学鉴定结果表明,与二倍体水稻对照相比其株高、穗长、花粉育性等主要农艺性状,确定四倍体材料在穗长和千粒重两方面极显著提高,种子的长度和宽度也显著增长。对花粉育性鉴定,确认水稻四倍体不育系材料仍为不育,保持系材料自交和杂交可育,恢复系材料自交和杂交可育。对四倍体材料进行细胞形态、染色体数目等方面进行细胞学鉴定,经核型分析表明水稻四倍体材料具有48条染色体,是二倍体水稻的两倍。水稻四倍体材料根尖分生组织细胞与二倍体的根尖分生组织细胞相比,细胞体积、细胞核和核仁显著增大。四倍体三系材料在细胞有丝分裂中期均可规则排列在赤道板,并能均等地移向两极;后期观察中没有发现染色体分离滞后现象,分裂末期细胞能够形成大小相对均一的子细胞。水稻同源四倍体三系材料细胞分裂未见异常,植株生长发育正常。 从1996年至2006年,针对结实率、有效分蘖、着粒数和穗长等主要农艺性状,通过系谱选育的方法,对培育的同源四倍体水稻亲本材料进行了连续选择和改良,取得较好成效。表现为结实率的改良效果极佳,所有改良材料的平均结实率均呈上升趋势,如D237(29.70%→72.70%)、DTB(19.55%→53.21%)等。有效分蘖总体呈现上升趋势,但在不同的年份,如1998和2002存在较大的负向波动。部分材料改良效果明显,如D19B(5.87→13.50)、D什香 (7.00→12.00)等;同时一些材料如DTB和D明恢63虽然总体略有提高,但在不同的年份波动很大,因此存在较大改良阻力,原因还有待进一步研究。着粒数的改良上升趋势比较显著,除保持系的DTB之外,其余材料的平均着粒数有显著提高。穗长的改良阻力较大,虽然不同材料总体上有所提高,但效果并不显著,并且不同年份有较大负向波动(2001)。此外还对株高、剑叶长等性状也进行了选择,但效果不显著,原因有待进一步提高。同源四倍体材料产量相关性状遗传改良幅度不一致,保持系和恢复系间的遗传改良效果也存在差异。这为同源四倍体水稻的进一步利用打下了良好的基础。 籼稻和粳稻亚种间杂交及杂种优势利用的主要障碍就是其低的结实率。而同源四倍体杂交水稻的研究为提高杂交水稻的杂种优势利用创造了新的途径。本研究通过随机区组设计方案,挑选性状优良的二倍体水稻材料,包括雄性不育系,保持系和恢复系进行秋水仙素诱导加倍,从而获得同源四倍体水稻对应的三系材料。利用选育的优良水稻同源四倍体三系材料,配制7个杂交组合,杂交F1代与其恢复系亲本进行比较,用于计算超亲优势(HB);而杂交F1代与生产上大面积推广的二倍体杂交品种汕优63进行比较,用于计算杂种优势。结果显示,同源四倍体杂交水稻的超亲优势表现为:每株有效穗变化幅度为1.4%至105.9%,总粒数为0.5%至74.3%,每穗实粒数为17.6%至255.7%,结实率为9.6%至130.4%。这些农艺性状的改良使得这7个杂种F1的理论产量的超亲优势高达64.8%至672.7%。小区试验中四倍体杂交水稻组合T461A/T4002和T461A/T4193分别比二倍体对照汕优63提高46.3%和38.3%以上,除一个品种以外所有品种产量均接近或高于汕优63的产量。同源四倍体水稻强大的杂种优势表明,亚种间杂交育性低的问题可通过四倍体化及强化选择来解决。此外,同源四倍体杂交水稻器官的巨大性也是其产量提高的有利因素,水稻同源四倍体三系杂种优势利用研究具有一定的理论价值和商业生产潜力。 Rice is one of the major food crops, the improvement of the production and quality of it is an important thing related to the people's livelihood. On China's current national conditions, steadily increase of the rice yield based on the current level is still one of the most important goals in the next decade or even decades of agricultural production. According to the "super hybrid rice breeding" the strategic and rice breeding practice, improvement of the use of hybrid rice heterosis through continuous improvements in breeding technology is expected to get a higher level of rice yield, there are also a great yield potential can be exploited. However, there are also some difficulties to increase rice yield obviously and implement the goal of "super hybrid rice" based on the existing germplasm: Rice varieties in promotion are diploid, although there are many varieties, but their genome are from a comparatively single source; Meanwhile, the rice genome DNA are the least among the crops, it is difficult to exploit the development potential within the genome; Rice as C3 plants, photosynthetic efficiency is not high, it is one of the factors constraint rice yield. Therefore, seeking technological breakthroughs or innovative methods different from conventional means is the urgent needs to reach the target of "super hybrid rice". Using colchicine inhibit spindle contraction during cell division, double the cell chromosome, we induced callus cells from rice panicle to be doubled, and differentiated regeneration; we created a new autotetraploid rice germplasm material, and on that basis we bred male sterility three line autotetraploid rice materials, and the achieved the three line rice autotetraploid matchmaking, researched in autotetraploid rice heterosis usage and tetraploid hybrid rice breeding, constituted a new technology system of autotetraploid hybrid rice heterosis utilization. This not only helps the tetraploid rice heterosis exploration and use, but also inaugurates a new technical means for China in the new century "super rice" breeding research. We chose ordinary diploid rice as materials, using colchicine to induce the polyploidization, created the autotetraploid rice three-line materials and identified them. The polyploidization was based on the colchicine-induced callus tissue culture, and we experimented different colchicine concentrations and culture mediums to induce tetraploid plants, confirmed that the optimal concentration for inducement was 500 mg/L, the average induce rate was 25.26 %. Among all the materials, CDR22 and IR26 had higher induced rate; in contrary, 94109 and GANG46B had lower induced rate, the difference was significant. Autotetraploid materials was identified of both morphological and cytological, compared plant height, length of pollen sterility, and other major agronomic traits with a diploid rice as the control plant, identified that the autotetraploid materials had very significant advantages in ear length and thousand-grain weight, as well as the size of the seeds. Cytology identification included observation of the cell morphology, the number of chromosomes, and karyotype analysis on the autotetraploid materials confirmed that their chromosome number was 48, twice of the diploid rice. Mitoses in the three lines were common: chromosomes arrayed normally in metaphase and separated balanced into the two poles, chromosome moved without lagging in anaphase and daughter cells normally formed in telophase except one. It has been proved that tetraploid rice has normal meiosis as their diploid relatives, which usually including series of sub-phases as interphase, prophase I (five sub-phases), prophase II, metaphase I, II, anaphase I, II and telophase I, II. However, abnormal phenomena, such as formation of tetravalent, trivalent and univalent, chromosome lagging and so on, which would finally block meiosis. Configurations of chromosome in metaphaseⅠwere versatile in structure and form accept the bivalent. That condition varied in different strain, suggesting more complex paring configurations and more versatile genetic characters in tetraploid rice. All these abnormalities in meiosis contributed to low fertility of gamete and might consequently resulted in low seed setting. Successive selection and improvement on seed set, productive tiller per plant, total grains per panicle, panicle length and so on had been carried out from 1996 to 2006. The raise of seed sets was significant in both restorers and maintainers. Seed sets of some strains were improved more significantly than others, for example D237(29.70%→72.70%)、DTB(19.55%→53.21%)and et al.. Productive tiller per plant was improved to some extant. The tendency of improvement was rising on the whole but changed in some years such as 1998 and 2002. Part of the stains increased greatly, such as D19B(5.87→13.50)、Dshixiang (7.00→12.00) and so on, but some strains including DTB and Dminghui63 only increased little and decreased in some years by unknown reason. Total grains per panicle increased significantly and all strains except DTB increased. Improvement of panicle length termed to be hard. Different strains showed different capacities for improvement and floating existed in different years for example 2001. It has been proved that other agronomical traits including plant length, flag leaf length and so on could be improved but not significantly by selection also. In a word, agronomical traits could be raised by successive selection that is prerequisite for further utility of autotetraploid rice. Poor fertility is the main barrier for utilizing heterosis between the two rice (Oryza stiva L.) sub-species, indica and japonica. Recently, the development of autotetraploid hybrids (2n=4x=48) has been suggested as a new method for increasing heterosis in hybrid rice. Using standard experimental protocols, the elite diploid rice male sterile, maintainer, and restorer lines were colchine-doubled and autotetraploid counterparts were obtained. Seven resulting hybrids were analyzed for heterobeltiosis (HB), where the F1 was compared to the male parent, and the degree of heterosis, where the F1 was compared to the diploid commercial hybrid, Shanyou 63. The HB among the autotetraploid hybrids ranged from 1.4 to 105.9% for the productive panicles per plant, 0.5 to 74.3% for total kernels per panicle, 17.6 to 255.7% for filled kernels per panicle, and 9.6 to 130.4% for seed set. Improvements in these yield components resulted in the HB for kernel yield ranging from 64.8 to 672.7% among the seven hybrids. Hybrids T461A/T4002 and T461A/T4193 yielded 46.3 and 38.3% more, respectively than Shanyou 63, and all other hybrids but one yielded the same or more than Shanyou 63. The high heterosis for yield suggests that hybrid sterility between two rice sub-species may be overcome by using tetraploid lines followed by intensive selection. Also, the gigantic features of the autotetraploid hybrids may establish a plant structure able to support the higher yield.

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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.