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花粉母细胞的减数分裂,是果树有性生殖过程中的一个重要环节。它持续的时间虽短,但对外界环境条件的反应非常敏感。此时如果花芽遭受冻害,或者树体内缺乏水分和养料,就会引起减数分裂异常,使花粉粒发育不良或出现败育现象,影响授粉受精,降低产量。因此,在生产中必须不失时机地采取相应的农业措施,以保证果树花粉母细胞减数分裂的正常进行。我们用压片法,在显微镜下对8种果树,15个品种的花粉进行观察。结果表明,当果树花粉母细胞进入减数分裂期,在植株的外形上会表现出一定的特征。核果类的果树,如樱桃、杏、桃的花粉母细胞在分裂时,花芽处于萌动期,并在花芽的顶部出现不明显的裂口、裂缝或小白点。分裂盛期的沙梨(砀山梨),在花芽的基部有不明显的绿色或褐绿色的小块。洋梨(如白
Meiosis of pollen mother cells is an important part of fruit tree sexual reproduction. It lasts for a short time, but it is very responsive to the external environmental conditions. At this point if the flower buds suffer frost damage, or the lack of water and nutrients in the tree, it will cause abnormal meiosis, pollen grains underdevelopment or abortion, affecting pollination and fertilization, reduce production. Therefore, we must seize the opportunity to take appropriate agricultural measures in the production, in order to ensure normal fruit tree pollen mother cell meiosis. Using the tabletting method, we observed the pollen of 8 species of fruit trees and 15 varieties under the microscope. The results showed that when the pollen mother cells into the meiosis stage, the appearance of the plant will show some characteristics. Drupe fruit trees, such as cherry, apricot, peach pollen mother cells in the division, flower buds in the germination period, and in the top of flower buds appear obvious cracks, cracks or white spots. Split pear (pear), the bud at the base of the obvious green or brown green small pieces. Pear (such as white