摘要
对燕麦叶片光合日变化测定结果表明 ,中午燕麦叶片净光合速率 (Pn)明显降低 (光合午休 ) ,日变化曲线呈双峰型 ,即上午 9:0 0～ 10 :0 0和下午 15 :0 0～ 16 :0 0净光合速率各有一个高峰 ,下午的峰值低于上午。两峰之间有一低谷 ,最低值出现在下午 14 :0 0。经相关分析发现 ,各生理生态因子与净光合速率 (Pn)的相关性大小排序为 :气孔阻抗 (Sr) >二氧化碳浓度 (CO2 ) >叶室温度 (Tc) >相对湿度 (RH) >叶片温度 (Tl) >水分利用效率 (WE) >蒸腾速率 (Tr) >光合有效辐射 (PAR)。
The measuring results with diurnal variations of photosynthesis in oat leaves shows that the net photosynthetic rate of oat leaves displays a significant middy depression at noon. Diurnal variations show a double peaks curve. The two peaks appear about 9:00 10:00 Am and 15:00 16:00 Pm respectively, and the latter was lower than the former. The lowest point between the two peaks appears about 14:00 Pm. According to the regression analysis, the sequence of correlation between each ecophysiological factor and Pn is Sr>CO> Tc>RH >Tl>WE>Tr>PAR. So stomatal closure is an important factor causing middy depression of photosynthesis.
出处
《草原与草坪》
CAS
2002年第1期34-37,共4页
Grassland and Turf
关键词
叶片
光合日变化
燕麦
净光合速率
气孔阻抗
饲料
oat
diurnal variation
middy depression of photosynthesis
net photosynthetic
