小麦白粉病对小麦CO_2同化量的影响

The Effect of Powdery Mildew on the Bates of Winter Wheat Photosynthesis

本文用差动式CO_2红外分析仪在田间直接测量了小麦白粉病(Erysiphe graminisD.C.f.sp.tritici)对不同生育期小麦单叶CO_2同化量的影响,结果表明:当白粉病严重度较小时,小麦单叶的最大净光合速率随严重度的增加呈指数下降;严重度较大时,随严重度的增加,最大净光合速率变化很小。结果还表明:白粉病对小麦CO_2同化量影响最大的生育期是扬花期,对蜡熟期的影响最小,而且健株健叶与病株健叶的最大净光合速率经统计检验无显著差异。

The photosynthesis rates of winter wheat leaves were measured at different developmental stages and at various disease severity with infrared gas analyzer. The results showed that the maximum rate of photosynthesis (Pmax) decreased exponentially with disease severity increment when disease severity was low and that the Pmax decrement was very small with disease severity increasing when disease severity was high. In the flowering stage, the effect of powdery mildew on photosynthesis rate was maximum. While in wax ripening stage, the effect was minimum. The Pmax of no spot leaves on mildew-infected plant and uninfected plant were not significant different.