灌浆期干旱对不同倍性小麦光合和产量的影响

为揭示灌浆期水分亏缺对不同倍性小麦光合特性和产量的影响,选用二倍体野生一粒、栽培一粒小麦,四倍体野生二粒、栽培二粒小麦,六倍体小麦"长武134"和"陕253"等6个小麦品种作为供试材料,通过盆栽控水方式,对不同倍性小麦旗叶净光合速率、瞬时水分利用效率和产量进行了研究.结果表明,在正常供水、轻度干旱和严重干旱3种水分处理下,不同倍性小麦旗叶净光合速率、水分利用效率和产量差异极显著.在灌浆过程中,水分亏缺对不同倍性小麦净光合速率变化趋势的影响不明显.而最大净光合速率和水分利用效率随水分胁迫的加重而减小.六倍体小麦平均最大净光合速率为22.03 μmol CO2·m-2·s-1),高于二倍体和四倍体小麦.六倍体小麦平均最大水分利用效率约为7.12 μmol CO2/mmol H2O ,分别是四倍体和二倍体的1.63倍和2.05倍,并且在灌浆开始时就达到最大.因此,小麦长期进化过程中,六倍体小麦花后较强的光合能力和较高的水分利用效率是提高小麦产量的重要生理基础.

Effect of Water Deficit on Photosynthetic Capacity and Yield of Different Ploidy Wheat during Grain Filling Stage

Taking six wheat species(two diploid Species of Triticum boeoticum,T.monococcum;two tetraploid species of T.dicoccoides,T.dicoccon;two hexaploid species of Changwu 134 and Shaan 253) as test materials,the net photosynthetic rate,water use efficiency of flag leaf and yield are measured under different water conditions during grain filling stage with pot experiment to reveal the effect of water deficit on grain photosynthetic capacity and yield.The results showed that net photosynthetic rate,water use efficie...