摘要： 系统测定了辣椒的净光合速率及其日变化。结果表明，参试品种的净光合速率在12～14μmolCO2·m-2·s-1之间，部分品种间差异显着或极显着。不同叶位间净光合速率明显不同，幼叶净光合速率较高，老叶净光合速率较低，健壮叶片净光合速率最高。净光合速率日变化为双峰曲线，有明显的“午休”现象。造成光合“午休”的原因，在10∶00之前以气孔限制因素为主；10∶00之后以非气孔限制因素为主。光量子通量密度明显影响辣椒净光合速率，光饱和点和补偿点分别为1800和50μmol·m-2·s-1.

关键词: 辣椒, 净光合速率, 日变化, 品种, 叶位, 光通量密度

Abstract: In this experiment the photosynthetic rates of pepper(Capsicum annuum L )were studied.The main results were as follows:1 The net photosynthetic rates (Pn)of some varieties were significantly different.Pn ranged from 12～14μmol CO 2?m -2 ?s -1 2 There were obvious differences in Pn for different leaf position,lower in the older leaf and higher in younger leaf,the highest in the middle leaf.3 The Pn varied in daytime,in a double peak curve and there was a“midday depression”in the noon.4 Photo flux density exerted significant effect on Pn.The saturation point was 1800 μmol?m -2 ?s -1 ,and the compensation point was 50 μmol?m -2 ?s -1 .

Key words: Pepper, Net photosynthetic rate (Pn), Daily variation, Photo flux density (PFD), Leaf position, Variety

中图分类号: 

• S641.301