关于糜胚胎发育的研究

糜为禾本科黍族作物.子房内有1倒生胚珠,双珠被,厚珠心.胚囊类型为蓼型,8核7细胞胚囊.成熟胚囊受精前1助细胞已解体.反足细胞4～5个,极核未融合.双受精过程中,卵受精后有三核仁现象,二极核与精核先后受精后,胚乳核先于合子分裂,游离核阶段约1.5～4天、第5天开始积累淀粉.合子休眠约20小时,第1次分裂为横裂,约12天胚分化完成,约22～28天籽粒成熟.反足细胞于花后6天胚分化开始,胚乳淀粉大量积累时消失.籽粒发育过程中的落粒现象应深入探讨.

A Study on Embryonic Development of Broomcorn Millet

The Broomcorn millet (Panicum miliaceum L. ) is a crop of Graminese Panicene. There was an anatropous ovule in the ovary which was double integument and crassinucellate ovule tissue. Its embryo sac was polygonum type which had 8 nuclei and 7 cells.In the ripe embryo sac, there were 4 - 5 antipodal cells, and one ofthe synergids degenerated before fertilization, but the polar nucleus did notfuse. ,In the process of double fertilization, the egg had 3 nuclei after fertilization. The endosperm nucleus divided earlier than that of zygote after two pole nuclei and sperm nucleus had fertilized successively.The free-nucleus stage lasted appoximatcly 1.5-4 days, and at the 5th day, the endosperms began to accumulate starch. The time of zygote dormancy was about 20 hours. The first division was cross. The accomplishment of embryo differentiation needed about 12 days.And at about 22-23 days, the seed got mature. The antipodal cell removed after G days of flowing when the embryo began to differentiate and starch in endosperm began to accumulate largely.