矮砧苹果树光合速率变化研究

红星苹果树光合速率的季节变化中,有二次高峰,出现在5月和8月,M9、M7砧树的峰值高于山定子砧树.光合速率的日变化中,高峰出现在上午,M9砧树在9时.M7、山定子砧树在11时.M9砧树光饱和点为420001X、M7和山定子砧树为48000—560001X.M9砧树在较低光照强度下利用光能较好,所以能积累较多的光合产物,有利花芽分化、果实发育.M7砧树的光合强度也高于山定子砧树.

A Study on the Changes of the Photosynthetic Rate of Apple Trees in Dwarfing Rootstocks

The photosynthetic rate of Starking apple trees in the growing season showed two peaks, in May and August, respectively. The peak values of apple trees on dwarfing rootstocks M9 and M7 were higher than that of the vigorous trees. In the diurnal variation of the photosynthetic rate, the peak showed in the morning, the highest photosynthetic rate of trees on M9 took place at 9 o'clock, the trees on M7 and vigorous rootstocks at 11 o'clock a. m. The light saturation point of photosynthesis of trees on M9 was 42000 lx and that of trees on M7 and vigorous rootstocks was between 43000-56000 lx. The trees on dwarfing rcotstock M9 can utilize low illumination better than vigorous trees, and it can accumulate more photosynthetic products. Therefore it is in favour of flower bud formation and fruit development. The photosynthetic intensity of trees on M7 was also higher than that of the vigorous trees.