灌浆期干旱对小麦旗叶衰老和籽粒产量的影响

Effect of Water Stress on Flag Leaves Senescence and Grain Yield of Winter Wheat in Grain Filling Stage

在高肥条件下，研究灌浆期干旱对两个抗旱性不同的旱地小麦品种旗叶衰老和籽粒产量的影响。结果表明，豫麦２号抗旱系数为０．９０，表现为旗叶叶绿素下降快，ＭＤＡ增加快，活性氧代谢失调出现的早；郑旱１号抗旱系数０．９７，表现为旗叶叶绿素降解缓慢，细胞膜脂过氧化代谢程度较低。Ｏ·２和Ｈ２Ｏ２的迅速累积与叶片衰老密切相关。干旱导致粒重下降的程度与品种抗旱性相一致。

The effects of water stress on flag leaves senescence and grain yield of two different droughtresistant varieties of winter wheat(Zhenghan No.1 and Yumei No.2) were studied under high fertilizer field conditions. The results showed that drought coefficient of Yumei No.2 and Zhenghan No.1 were 0.90 and 0.97, respectively. In the grain filling stage, the chlorophyll degradation and MDA accumulation in Yumei No.2 were faster than in Zhenghan No.1 under water stress, which means the degree of lipid peroxidation in zhenghan No.1 was lower than in Yumei No.2. The rate of O 2 producing and content of H2O2 increasing rapidly in laterfilling stage caused earlysenescence of wheat flag leaves under water stress. The decline of grain weight in Yumei No.2 was grater than that in Zhenghan No.1.\;