【作者】 杨梅；

【导师】 陈耀锋；

【作者基本信息】 西北农林科技大学 ， 作物遗传育种， 2012， 硕士

【摘要】 小麦是世界主要的粮食作物之一，世界上约70%的小麦分布于干旱和半干旱地区，由于气候及生态环境的恶化导致干旱问题越来越严重的影响着我国小麦的安全生产，所以，挖掘和利用抗旱节水相关的基因资源改良小麦的耐旱性对小麦的安全生产具重要的意义。本研究以3个转TaEREB1基因小麦株系（G9-X1123、G9-X1125、G9-X1127）和4个转TaEREB2基因小麦株系（G9-X1129、G9-X1134、G9-X1136和G9-X1139）、受体对照新春9号、当地（陕西）推广品种小偃22以及国审区试对照品种晋麦47为材料，通过室内PEG模拟干旱胁迫处理和大田控水处理，分别对转TaEREB1、TaEREB2基因小麦萌发期胚芽鞘长度、胚根长度、胚根数目和生长发育中后期叶片相对含水量、相对电导率、可溶性蛋白含量、脯氨酸含量、丙二醛含量、叶绿素含量、光合速率和蒸腾速率等抗旱相关生理生化指标变化、农艺性状表现、抗旱指数及产量分析等进行了系统研究，综合分析评价了转TaEREB1和TaEREB2基因小麦株系的抗旱节水性能，获得了以下研究结果：1室内PEG模拟干旱胁迫研究表明：在20%（W/V） PEG-6000模拟干旱处理下，转TaEBP基因小麦株系及参试小麦品种种子萌发期的胚芽鞘长度、胚根长度和胚根数都有不同程度的缩短或减小，受体对照新春9号降幅较大，转基因株系G9-X1123、G9-X1125、G9-X1127、G9-X1129、G9-X1134、G9-X1136和G9-X1139降幅较小；小偃22降幅与转TaEBP基因株系无显著差异，而晋麦47受胁迫伤害相对较小。2大田控水处理条件下转TaEBP基因小麦株系及对照品种不同生育期相关生理生化指标测定结果表明，在零水（W₀）、一水（W₁）和二水（W₂）三种灌水处理下，随着水分胁迫程度的增强及小麦生长发育进程的推进，各参试材料的叶片相对含水量（RWC）、叶绿素含量和叶片光合速率都呈现不断下降的变化趋势，与受体对照新春9号相比，转TaEBP基因植株的下降幅度相对较小，且始终维持在相对较高的水平；转TaEBP基因植株与对照品种的叶片可溶性蛋白含量和脯氨酸含量随着水分胁迫程度的加剧而不断的积累，其叶片蒸腾速率也呈现不断增加的趋势，转TaEBP基因植株的累积和增加幅度均比受体对照新春9号大；水分胁迫处理下转基因株系G9-X1123、G9-X1125、 G9-X1127、G9-X1129、G9-X1134、G9-X1136和G9-X1139的叶片相对电导率和丙二醛（MDA）含量增加量比受体对照新春9号小，表明转TaEBP基因株系能够进行有效调节自身的细胞质膜透性和渗透调节等过程，以适应土壤或环境的水分胁迫。3大田控水处理条件下转TaEBP基因小麦株系及对照品种农艺性状表现及产量分析结果显示：在零水（W₀）、一水（W₁）和二水（W₂）三种灌水处理下，随着灌水次数的减少，转TaEBP基因株系与对照品种的株高、穗叶距、穗长、穗粒数均不同程度的降低，而转TaEBP基因植株始终保持较低于新春9号的下降幅度，在水分胁迫下转基因植株能保持相对较稳定的农艺性状表现；在零水（W₀）和一水（W₁）处理下，转TaEBP基因植株的单株重和百粒重明显高于受体对照新春9号；在零水（W₀）处理下，转基因株系G9-X1123、 G9-X1125、 G9-X1127、G9-X1129、G9-X1134、G9-X1136和G9-X1139分别比受体对照新春9号增产10.76%、29.08%、13.94%、13.95%、10.36%、10.76%和12.75%，相对应于新春9号的抗旱指数分别为1.27、1.34、1.19、1.24、1.10、1.13和1.19，均属较强抗旱等级品种，其耐干旱胁迫能力明显比受体对照新春9号强。更多还原

【Abstract】 Wheat is a kind of important food crop in the world, about70%in the worlddistribution of wheat in arid and semi-arid area. It has great significance in exploring andutilizing the drought-resistant gene resources to enhance or improve drought-resistant abilityof wheat today. Three transgenic wheat（G9-X1123, G9-X1125, G9-X1127） with TaEREB1gene and four transgenic wheat（G9-X1129, G9-X1134, G9-X1136, G9-X1139） withTaEREB2gene, receptor parent Xinchun No.9, local contrast varieties Xiaoyan22andJinmai47were used as materials. In order to comprehensively analysis and evaluate thedrought-resistant performance of transgenic plants, the materials were being investigated theircoleoptile length, radicle length and radicle numbers of wheat seedlings under PEG osmoticsolution simulated drought stress, and being further analyzed their physio-biochemical andmorphological characters （such as relative water content, relative electric conductivity,soluble protein content, proline content, MDA content, chlorophyll content, photosynthesisrate, transpiration rate） and yield or drought resistance index under different water treatmentsat field case in the middle and late growth and development stage.1The results indicated that, the coleoptile length，radicle length and radicle numbers oftest materials had been shorted or decreased in different degrees under20%concentrationsPEG-6000osmotic solution simulated drought stress, and the receptor control showed asignificant decrease while the transgenic lines G9-X1123、G9-X1125、G9-X1127、G9-X1129、G9-X1134、G9-X1136and G9-X1139showed a modest one; The descender of Xiaoyan22andtransgenic strains were not significantly different, and Jinmai47was injuried relatively smallwith stress.2Under field case at moisture critical period, with the enhancing of water stress andadvancing of the process of growth and development of wheat, the relative water content,chlorophyll content and photosynthetic rate of all materials showed a decreasing tendency, buttransgenic plants showed a slight decrease and hovered at a high level in contrast tonon-transgenic one；the leaf soluble protein and proline content of transgenic lines and thecontrasts increased with the increasing extent and duration of drought stress, as well as thetranspiration rate, but transgenic plants showed a slight accumulation and increase in contrastto non-transgenic one；The leaf relative electric conductivity and malondialdehyde content oftransgenic lines, G9-X1123, G9-X1125, G9-X1127, G9-X1129, G9-X1134, G9-X1136,G9-X1139, slightly increase in contrast to Xinchun No.9under the water stress, which indicated that the transgenic plants could effectively perform the physiological autoregulationat the aspects of cell membrane permeability of leaf and regulation ability to adapt the waterstress of soil or environment.3The results of agronomic traits and yield analysis at middle and late wheat growthstage showed that, Under three different irrigation levels, W₀, W₁and W₂, the plant height,space of spike leaf, spike length and grain number per spike of all materials had differentlevels of reduction with reducing the number of irrigation, and transgenic plants showed aslight decrease in contrast to Xinchun No.9, which could maintain a relatively stableagronomic performance under water stress. Under W₀and W₁conditions, the grain weight perplant and100-grain weight of transgenic lines were much higher than Xinchun No.9. Underthe W₀condition, the yield of G9-X1123, G9-X1125, G9-X1127, G9-X1129, G9-X1134,G9-X1136, G9-X1139respectively exceed Xinchun No.9by10.76%,29.08%,13.94%,13.95%,10.36%,10.76%,12.75%, and the drought index respectively were1.27,1.34,1.19,1.24,1.10,1.13,1.19, which belong to a strong drought-resistant level. The resultsdemonstrated that the transgenic plants show stronger resistance to drought than XinchunNo.9.更多还原