不同辐照日变化系统对葡萄（V.vinifera L.cv.Sauvignon blanc）净光合和气孔导性的影响

 自然条件和控制条件下的实验证明，由叶幕形式所调控的辐照日变化系统对葡萄净光合速率日变化类型产生很大影响。最大蒸腾条件下群体中葡萄叶片一天中的光合能力在上午最大，尔后叶肉CO#-2内阻升高，光合持续下降。所以叶幕上午最大限度的光能截留对提高光合产量发生最有效的作用。光合作用“午间低谷”现象的调控与光合作用代谢物质的反馈调节有关。最后，对各种光能截留面形式的叶幕在生产上的应用问题作了讨论，肯定了各种南北行向叶幕对于合理利用光能和提高群体光合产量的重要意义。

EFFECTS OF THE DIURNAL LIGHT VARIATION REGIME ON NET PHOTOSYNTHETIC RATE AND STOMATAL CONDUCTANCE IN GRAPEVINE (V.vinifera L.cv.Sauvignon blanc)

The experiments under natural and phytotron conditions show that the diurnal light variation regimes, created by different light interception planes or canopy structures, have considerable influence on diurnal variation characteristics of net photosynthetic rate of grapevine. In the plant canopy with maximum transpiration conditions, the photosynthetic capacity of grapevine leaves reaches to maximum around the middle of morning, and thereafter decreases continuously during the day particularly with an increase in internal resistance to Co_2. It is therefore considered that a maximum light interception by canopy during the morning constitutes a most efficient way to improve the photosynthetic production environment of vineyard. The mechanism of midday depression of photosynthesis is supposed to be related partly to feed-back effects in leaves. Finally, the practical efficiency concerning the photosynthetic production of the different light interception planes has been discussed, and furthermore the different North-South orientation planes as most efficient for light interception and photosynthesis have been considered.