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机构地区:[1]中国科学院植物研究所,北京林业大学森林资源与环境学院
出 处:《北京林业大学学报》1994年第2期10-14,T001,2,3,共8页Journal of Beijing Forestry University
摘 要:华北落叶松的雄球花7月中旬开始分化,小孢子发生在次年的3月下旬至4月上旬,4月底散粉,成熟花粉为五个细胞。雌球花7月初分化,翌年4月上、中旬形成大孢子母细胞,经减数分裂后,形成大孢子。雌配子体经历游离核、细胞化、颈卵器及卵细胞形成几个阶段后,6月上、中旬受精,从传粉到受精约需40d.胚胎发育包括原胚、胚胎选择及发育和胚胎成熟3个阶段,历时两个半月。The male flower differentiates in middle July, while the female flower in earlyJuly. The microsporogenesis occurs in late March and early April of the next year. The ma-ture pollen, which is pollinated in late April, is composed of 5 cells. The megasporocyte isformed in early and middle April of the next year and undertakes meiosis to form megasporein early May. A female gametophyte develops from free nuclei, cell and archegonia phase to amature egg cell. Fertilization takes place in early and middle June. The interval between polli-nation and fertilization is about 40 days. Embryogeny includes proembryo, young embryo andmature embryo and needs two and a half months.
分 类 号:S791.220.1[农业科学—林木遗传育种]
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