一、枣树生育要求的外界条件(一)温度枣在生育期间要求较高温度,当气温达到13—15℃时芽才开始萌动,生长最适温度在17℃以上,开花要求22—28℃,花粉发芽需24—26℃,若花期气温较低,会影响受精、果实发育和座果。果实成熟需要18—22℃的气温。生长期间能忍受43.3℃的高温,休眠期间能忍受-35℃的低温。山西绝大部分地区都能满足枣对温度的要求。(二)光照枣树原产于日照充足的晋陕黄土高原,为喜光果树,所以在山谷、沟地等光照不良地段栽植,或者树冠郁闭时,常发生徒长性枣头, A jujube tree requirements of the external conditions of (A) temperature Jujube during the growing period requires a higher temperature, when the temperature reaches 13-15 ℃ bud began to sprout, the optimum growth temperature above 17 ℃, flowering requires 22-28 ℃ Pollen germination required 24-26 ℃, if the flowering temperature is low, will affect the fertilization, fruit development and fruit. Fruit ripening requires a temperature of 18-22 ° C. During the growth can tolerate 43.3 ℃ high temperature, during sleep can tolerate -35 ℃ low temperature. Most parts of Shanxi can meet the jujube temperature requirements. (B) of the jujube light originated in the Sunshine sufficient Jin and Shan Loess Plateau, for the happy light fruit trees, so in the valley, ditch and other places of poor light planting, or canopy canopy, often occurs leggy jujube,