花后干旱和渍水对冬小麦光合特性和物质运转的影响

在温室盆栽条件下，以黑小麦76、皖麦38、扬麦10号、扬麦9号4个蛋白质含量不同的冬小麦(Triticum aestivum L.) 基因型为材料，研究了花后土壤干旱（Soil relative water content, SRWC=45%～50%）、渍水和适宜水分条件（SRWC=75%～80%）下，小麦旗叶净光合速率和叶绿素含量的动态变化，营养器官花前贮藏同化物再运转，花后同

Effects of Post-anthesis Drought and Waterlogging on Photosynthetic Characteristics, Assimilates Transportation in Winter Wheat

Four winter wheat( Triticum aestivum L.) genotypes differing in grain protein content, Heixiaomai 76, Wanmai 38, Yangmai 10 and Yangmai 9, were used in pot experiment in greenhouse to investigate the effects of drought (Soil relative water content, SRWC=45%-50%), waterlogging and moderate soil water status (SRWC=75%-80%) after anthesis on net photosynthesis and chlorophyll contents of flag leaves, remobilization of assimilates stored before anthesis, transportation of post-anthesis assimilates, and contents and yields of starch and protein in grain at maturity. It was found that the photosynthetic active duration (PAD) and the relative steady phase of chlorophyll content( RSP) of flag leaves of four wheat genotypes were shortened by both drought and waterlogging. Values of PAD and RSP declined from CK, via waterlogging then drought. The remobilization rate of pre-anthesis stored assimilates was the highest for CK, while the lowest for waterlogging. The amounts of post-anthesis assimilates and accumulated nitrogen transferring into grain were declined as CK>waterlogging>drought and CK>drought>waterlogging, respectively. The yield of grain protein significantly decreased at 5% level with the order of CK> drought > waterlogging in four wheat genotypes. The contents of grain protein increased significantly under drought, but had no significant difference between CK and waterlogging. Compared with CK, starch yield significantly decreased under drought and waterlogging in four wheat genotypes, but starch content was various among four wheat genotypes. These results showed that the amount of post-anthesis assimilates transferring into grain decreased distinctly under drought, while the remobilization of pre-anthesis stored nitrogen and the transferring of post-anthesis accumulated nitrogen into grain declined distinctly under waterlogging, which led to differences in protein and starch contents of wheat grains under post-anthesis drought and waterlogging. It is inferred that the transferring of post-anthesis accumulated nitrogen into grain and the remobilization of pre-anthesis stored nitrogen were vital factors to determine protein yield under the drought and waterlogging condition, respectively.