【摘要】 通过 3年对棉叶净光合速率的研究结果表明 :棉叶光合速率最大出现在盛蕾期至开花期。打顶前棉花主茎倒 4叶光合速率最大 ,打顶后倒 1叶和倒 2叶光合速率最大。开花期前倒 4叶光合速率日变呈双峰曲线 ,峰值出现在 1 2∶ 0 0～ 1 4∶0 0和 1 6∶ 0 0～ 1 8∶ 0 0 ,且第一个峰值比第二个峰值高 ,盛花期后因品种不同而有所不同。盛花期前主茎叶光合速率较大 ,盛花期后果枝叶光合速率较大 ,不同叶位的叶片光合速率变化规律有所不同。棉叶展平 1 4d后光合速率达到最大值。化学调控、揭膜时期、追施尿素对棉花的光合速率均有较强的调节作用。更多还原

【Abstract】 The results of three years(1998~2000) indicated that the maximum net photosynthesis rate(Pn) of cotton leaf appeared at the full squaring stage to the blooming stage. The photosynthesis rate of the forth leaf from the top to bottom varied according to two peak curves in a day before the blooming stage. The peak value appeared at 12∶00~14∶00 and 16∶00~18∶00, with the first peak value exceeded the second. The Pn of the main stem leaf is higher before the full blooming stage, While the Pn of the fruit branch leaf is higher after the full blooming stage. The Pn of the leaves reached maximum after 14 days.更多还原