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通过石蜡切片、压片等方法观察研究同源四倍体西瓜授粉、受精和胚胎发育过程发现：（１）同源四倍体西瓜花粉萌发率低，花粉管在生长过程中出现畸形现象，生长速度缓慢，授粉后１２小时到达花柱基部，比对照二倍体西瓜慢３小时；（２）四倍体西瓜的正常发育成熟胚囊为标准８核胚囊，自交受精过程正常，但有花粉管进入的胚囊数少，仅３５．０％（对照为９７．５％）：（３）四倍体西瓜自交部分胚胎在发育过程中球形胚阶段败育，只有少部分能发育到成熟，形成有活力的种胚。以上三方面是造成同源四倍体西瓜低稔性的主要胚胎学原因。
Through paraffin section, tabletting and other methods to observe the autotetraploid watermelon pollination, fertilization and embryonic development found that: (1) autotetraploid pollen germination rate is low, pollen tube growth during deformity, growth Slowly, 12 hours after pollination to reach the base of style, compared with the control diploid watermelon slow 3 hours; (2) the normal development of tetraploid watermelon mature embryo sac as a standard 8 nuclear embryo sac, selfing fertilization process is normal, but pollen The number of embryo sacs entering the tube was small, only 35.0% (control 97.5%): (3) tetraploid watermelon self-fertilized embryos in the developmental stage of the spherical embryo abortion, only a small part of the development to mature , Forming a dynamic seed embryo. The above three aspects are the main reasons for embryogenesis of the tetraploid watermelon.