外源糖氮调控对春小麦花后旗叶光合特性和物质转运的影响

Effects of Exogenous Sugar and Nitrogen on Photosynthetic Characteristics and Assimilate Translocation in Flag Leaf Post-Anthesis of Spring Wheat

以筋性不同的春小麦品种龙麦33和克旱19为材料,研究了外源糖氮调控下小麦花后旗叶光合特性的变化和营养器官花前、花后贮藏干物质与子粒产量和品质形成的关系。结果表明,施入外源糖氮均提高了旗叶光合速率,但外源糖处理降低了叶绿素含量(SPAD值)。小麦营养器官花前贮藏干物质转运量(TAA)和转运率(TAR)在外源糖氮调控下降低,花后物质积累量(PAA)升高。子粒产量在外源糖氮调控下均增加,子粒蛋白质含量以外源糖处理最高。外源糖氮调控下小麦千粒重和子粒蛋白质含量的提高与花后较高的光合能力及干物质积累有关,且PAA和花后物质积累对子粒产量的贡献率(CPA)与子粒品质呈正相关。

Using spring wheat varieties Longmai 33 and Kehan 19 as test materials,the post-anthesis photosynthetic characteristics in flag leaves, the translocation of assimilates in vegetative organs before and after anthesis and their relationships with grain yield and quality were studied in this paper. The results showed that exogenous sugar had positive effects on photosynthetic rate, but exogenous nitrogen had negative effects on chlorophyll content （SPAD value） in flag leaves. The translocation amount and translocation rate of assimilate in vegetative organs before anthe- sis declined under exogenous sugar and nitrogen were applied, while the assimilate accumulation elevated after the anthesis. The grain yield increased by exogenous sugar and nitrogen, and the protein contents in grains reached the highest under exogenous sugar treatment. Overall, the increase of grain mass and protein content under exogenous sugar and nitrogen was associated with the higher photosynthetic rate and post-anthesis assimilates accumulation, while post-anthesis assimilate accumulation was positively cprrelated to contribution of post-anthesis assimilate to grain yield and grain quality.