田间条件下转玉米C4型PEPC基因小麦的光合生理特性  

Physiological Characteristics of Photosynthesis in Transgenic Wheat with Maize C_4-PEPC Gene under Field Conditions

作　　者：吴琼[1,2,3] 许为钢[1,3] 李艳[1,3] 齐学礼[1,3] 胡琳[1,3] 张磊[1,3] 韩琳琳[1,3] 

机构地区：[1]河南省农业科学院小麦研究中心,河南郑州450002 [2]南京农业大学作物遗传与种质创新国家重点实验室,江苏南京210095 [3]省小麦生物学重点实验室,河南郑州450002

出　　处：《作物学报》2011年第11期2046-2052,共7页Acta Agronomica Sinica

基　　金：国家重点基础研究发展计划(973计划)前期专项(2009CB126000-9);国家自然科学基金项目(30971785);国家转基因生物新品种培育科技重大专项(2011ZX08002-003);国家科技支撑计划项目(2011BAD07B00);河南省杰出青年基金(104100510021)资助

摘　　要：为了检验转PEPC基因小麦是否具有C4光合生理特性,以转PEPC基因小麦和对照周麦19为试验材料,分别于抽穗期、开花期、花后第7天和花后第15天测定其单株旗叶的气体交换参数日变化,对净光合速率日变化进行单位日光合总量分析,并且对净光合速率日变化与单株气孔导度、胞间CO2浓度、蒸腾速率日变化的相关性进行了分析;在花后第15天测定其单株叶绿素荧光参数,并在成熟期调查了单株产量性状。与对照相比,转基因株系在4个测定时期的旗叶净光合速率明显提高,尤其在花后第15天,单位日光合总量较对照提高29.1%和23.3%,气孔导度和蒸腾速率均明显增加,胞间CO2浓度降低;花后第15天12:00与8:00相比,转PEPC基因小麦的Fv/Fm、qP、NPQ、ΦPSII的变幅均小于对照;单茎重、千粒重、单穗重和收获指数较对照显著增加。以上结果表明,转PEPC基因小麦材料在田间条件下光合特性明显优于对照,且具有提高小麦产量水平的潜力。Transformation and high efficiency expression of key enzymes gene of C4 photosynthetic characteristics are the important approach to improve photosynthetic efficiency and seed yield for C3 crop wheat. Phosphoenolpyruvate carboxylase （PEPC） plays an important role in C4 pathway. The authors have obtained several transgenic wheat lines with maize C4 type PEPC gene. To explore the expression and functional characteristics of PEPC gene in transgenic wheat plants, PCR test, PEPC activity, gas exchange parameters, chlorophyll fluorescence parameters and yield related characteristics of transgenic wheat lines were determined, using untransformed wheat as the control, and the value of diurnal photosynthesis cumulative （VDPC） at the four stages and the correlations between net photosynthesis rate and stomata conductance, intercellular CO2 concentration and transpiration rate were analyzed. The results showed that in the four determination stages, net photosynthetic rate of transgenic wheat obviously increased. For instance VDPC was increased by 29.1% and 23.3% on the 15th day after anthesis. Stomatal conductance and transpiration rate in flag leaves of transgenic wheat obviously increased compared to the control, and intercellular CO2 concentration decreased. Net photosynthetic rate of transgenic wheat enhanced by 23.2%, and variation scope of Fv/Fm, qP, NPQ, and ΦPSII of transgenic wheat was smaller than that of the control from 8：00 to 12：00 on the 15th day after anthesis; the major yield characteristics, such as weight per stem, thousand grain weight, single spike weight and harvest index of transgenic wheat, were significantly higher than those of the control. The results described above indicated that the transgenic wheat expressing maize PEPC gene showed better photosynthetic characteristics than untransformed plant and has the potential to increase wheat yield.

关 键 词：磷酸烯醇式丙酮酸羧化酶 转基因小麦 光合特性 

分 类 号：S512.1[农业科学—作物学]