Hongbo Shao, Zongsuo Liang, Mingan Shao, Shimeng Sun, Zanmin Hu
State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, The Center of Soil and Water Conservation and Eco-environmental Research, The Chinese Academy of Sciences, Yangling 712100, PR China.
Colloids Surf B Biointerfaces. 2005 Jul 10;43(3-4):221-7. doi: 10.1016/j.colsurfb.2005.05.005.
Drought is a worldwide problem, seriously influencing plant (crop) productivity. Wheat is a stable food for 35% of the world population, and moreover, about 60% of land area on the globe belongs to arid and semiarid zone. Wheat drought resistance is a multi-gene controlling quantitative character and wheat final production in field is realized mainly by physiological regulation under the condition of multi-environmental factor interaction. Exploring drought resistance physiological mechanisms for different wheat genotypes is of importance to finding new drought resistance gene resources and conventional breeding, and the basis for wheat drought resistance biotechnological breeding and platform. Photosynthesis is the main component for physiological machinery of wheat assimilates conversion and wheat production. Investigation on photosynthetic characteristics of different wheat genotypes at soil water deficits also has other implications for refine physiological regulation of photosynthesis in fields and field management of crops in arid and semiarid areas. By pot-cultivating experiments, investigation of photosynthesis for 10 wheat genotypes at seedling stage and tillering stage at soil water deficits (75%FC, 55%FC and 45%FC, respectively) was conducted. The main results were as followed: developmental stages influenced wheat photosynthesis greatly and tillering stage played more roles; there were significant difference in the main photosynthetic parameters, photosynthesis rate (Photo), stomatal conductance (Cond) and transpiration rate (Tr), among 10 wheat genotypes; general photosynthesis and drought resistance in different wheat genotypes was related much to their domesticated origin soil water environment and selected generations and there was a photosynthetic threshold effect in terms of different wheat genotypes at soil water deficits.
干旱是一个全球性问题，严重影响植物（作物）生产力。小麦是全球35%人口的主要粮食，此外，全球约60%的土地面积属于干旱和半干旱地区。小麦抗旱性是一个受多基因控制的数量性状，田间小麦最终产量主要是在多环境因子相互作用条件下通过生理调节实现的。探索不同小麦基因型的抗旱生理机制对于寻找新的抗旱基因资源和常规育种具有重要意义，也是小麦抗旱生物技术育种及平台的基础。光合作用是小麦同化产物转化和产量形成生理机制的主要组成部分。研究不同小麦基因型在土壤水分亏缺条件下的光合特性，对于精细调控田间光合作用以及干旱和半干旱地区作物的田间管理也具有重要意义。通过盆栽试验，对10个小麦基因型在土壤水分亏缺（分别为75%田间持水量、55%田间持水量和45%田间持水量）条件下苗期和分蘖期的光合作用进行了研究。主要结果如下：生育期对小麦光合作用影响较大，分蘖期作用更显著；10个小麦基因型的主要光合参数，即光合速率（Photo）、气孔导度（Cond）和蒸腾速率（Tr）存在显著差异；不同小麦基因型的总体光合能力和抗旱性与其驯化起源的土壤水分环境及选择世代密切相关，且不同小麦基因型在土壤水分亏缺时存在光合阈值效应。
