摘要
陆地棉花粉和胚囊的发育全过程，都可以分为两个阶段。第一阶段为大、小孢子母细胞经减数分裂产生大、小孢子；第二阶段由大、小孢子经有丝分裂产生胚囊和花粉。本试验３年的观察结果，由大孢子母细胞产生大孢子持续时间约４天左右；从大孢子产生成熟胚囊所需时间约６天左右，全过程历时１０天左右。由小孢子母细胞产生四分孢子持续时间约３天左右；从单核小胞子到发育成熟的二核花粉约需７天左右，全过程历时１０天左右。胚囊和花粉发育的迟早，受气候条件影响较大。
After a long observation and investigation it was found that the whole formationcourse of pollen grain and embryosac of upland cotton might be divided into two stages. Thefirst stage deaIt with producing microspores and megaspores through meiotic division of pollenmother cells as well as megaspore mother cells. The second stage was devoted to the formationof pollen grains and embryosac by means of mitosis of microspores and megaspores. The courseof megaspores evolving from megaspore mother cells took about 4 days while the duration ofdeveloping mature embyosac from megaspores lasted 6 days. Hence the whole course totaledabout l0 days. The time needed for the development from microspore to tetrad was proved tobe about 3 days,and the approximate period for the development from mononucleate spore todinucleate spore turned out to be 7 days. The whole course took l0 days. The time of initia-tion of em byosac and pollen grain development was influenced mainly by the climatic condi-tions。
出处
《棉花学报》
CSCD
北大核心
1994年第3期129-131,共3页
Cotton Science
关键词
陆地棉
花粉
胚囊
发育全过程
upland cotton,pollengrain,embryosac,developmeantal course
