Abstract:

Four winter wheat ( Triticum aestivum L.) varieties (“JD 8”, “Jing 411”,“Centurk” and “Tam 202”) were used to study the effect of heat stress on photosynthetic characteristics of flag leaf blade, flag leaf sheath, peduncle, glume, lemma and awn during grain-filling stage. The results showed that heat acclimation during grain-filling stage increased thermotolerance of wheat with significant differences among different green organs. During heat stress, the decreases of the efficiency of primary light energy conversion ( Fv/Fm ) of PS and pigment (chlorophyll and carotenoid) content were much slower in peduncle, flag leaf sheath and glume than in flag leaf blade, lemma and awn; and the percentage of decrease in net photosynthetic rate ( Pn ) of ear was lower than that of the flag leaf blade. The measured photosynthetic parameters ( Fv/Fm , Pn and pigment content) of “JD 8”， a relatively heat tolerant variety, declined more slowly than those of the other three varieties during the whole heat stress period. 

灌浆期热胁迫对小麦不同绿色器官光合性能的影响
徐晓玲* 王志敏 张俊平
（中国农业大学作物学院，北京100094）

关键词： 冬小麦；旗叶；净光合速率；叶绿素荧光动力学参数；耐热性

Key words: XU Xiao-Ling, WANG Zhi-Min, ZHANG Jun-Ping