不同耐光特性植物的光合速率日变化

以耐强光植物玉米掖单１３号、耐弱光植物辣椒海椒１７号、中性耐光植物水稻汕优６３为材料，对其在不同光照条件下的光合速率日变化特征与叶绿素ａ／ｂ比值、ＳＯＤ活性进行了研究，结果表明：在夏季，不同耐光特性植物的光合速率日变化均为双峰型，下午的高峰比上午的低，在自然光照下，３种植物的光合速率、ＳＯＤ活性、叶绿素ａ／ｂ比值均为玉米〉水稻〉辣椒，但午睡程度却是辣椒〉水稻〉玉米，利用弱光的能力大小为辣椒〉水稻〉

THE DAILY CHANGE OF PHOTOSYNTHETIC RATE IN DIFFERENT LIGHTTOLERATING PLANTS

Using three different lighttolerating plants as materials, weak light tolerating green peeper plants, moderate light tolerating paddy rice plants and strong light tolerating maize plants, we examine the daily changes of photosynthetic rate in these plants under different light intensities, their chlachlb ratios and SOD activities. The results show that in summer, the daily changes of photosynthetic rate in all these plants are doublepeaked namely, one peak in the morning and the other in the afternoon. The former peak is higher than the latter and there is a between them valley, the socalled afternoon nap. However, under the same light condition, their photosynthetic rates are different, and the time that the peaks appear is also different, the ratios of chlachlb and SOD activities show similar trend to their related daily changes of photosynthetic rates.