限量灌溉对冬小麦光合与叶绿素荧光的影响

Effects of Limited Irrigation on Photosynthesis and Fluorescence of Winter Wheat

对限量灌溉条件下冬小麦光合与叶绿素荧光变化规律进行了分析,并探讨了冬小麦光合的气孔与非气孔限制情况。结果表明:轻度限量灌溉对冬小麦光合与叶绿素荧光没有显著影响;在开花期、灌浆初期,中度、重度限量灌溉造成的气孔限制是降低光合速率的主要原因;灌浆末期,中度、重度限量灌溉导致PSⅡ最大光化学效率显著降低,非气孔限制成为降低光合速率的主要因素。

Variations of photosynthesis and chlorophyll fluorescence for winter wheat leaves under limited irrigation were analyzed.Meanwhile stomatal and non-stomatal limitations of photosynthesis in winter wheat under limited irrigation were also discussed.The results indicate that mild limited irrigation does not significantly affect photosynthesis and chlorophyll fluorescence.At the flowering and early grain filling stages,stomatal limitation resulted from moderate and severe limited irrigation is the major factor resulting in the reduction of photosynthesis rate.However,at the late grain filling stage,the maximum photochemical efficiency of photosystem II is significantly reduced due to moderate and severe limited irrigation,and non-stomatal limitation becomes the major factor in reducing the photosynthesis rate.