白桦雌花发育、大孢子发生及胚胎发育的解剖学观察  

THE ANATOMIC OBSERVATION OF THE DEVELOPMENT OF FEMALE FLOWER MEGASPOREGENSIS AND THE DEVELOPMENT OF EMBRYO OF BETULA PLATYHYLLA

作　　者：姜静[1] 李同华[1] 庄振东 杨传平[1] 

机构地区：[1]东北林业大学,哈尔滨150040 [2]内蒙古兴安盟五岔沟林业局,五岔沟137803

出　　处：《植物研究》2003年第1期46-50,T007-T009,共8页Bulletin of Botanical Research

基　　金：国家自然科学基金资助项目 ( 39970 6 2 7)

摘　　要：白桦雌花从开花到雌性器官的成熟需经历 1个月左右的时间 ,解剖学观察表明 :四月下旬越冬的雌蕊原基开始了活跃的分裂和分化 ,子房和柱头开始生长。四月末开花 ,五月初授粉。此后胚珠开始长大 ,五月中旬即分化形成珠被、珠心。珠被为单层珠被 ,胚珠为厚珠心胚珠 ,胚珠倒生。五月中下旬 ,珠心内产生大孢子母细胞 ,一周左右发育为成熟胚囊———七细胞八核胚囊 ,五月末完成双受精。白桦胚胎发育经过合子、原胚、球形胚、心形胚和鱼雷形胚等时期最后发育成熟。胚乳发育与胚胎同步 ,即受精的极核进行几次分裂后形成核型胚乳 ,胚乳核不断增多 ,在形成心形胚后胚乳细胞形成细胞壁。The development of female flower of Betula platyhylla and the processes of maturity of female organ should be undergoing approximately one month. Anatomic observation suggests as follows. In late April, primitive pistil began to undergo cell division and cell differentiation after dormancy. Ovary and stigma was growing at that time. Floral bloom and pollination happened respectively in the end of April and the beginning of May. After that and nucellus tissue ovules grew and differentiated integument from ovule in the middle May. Betula platyhylla has single integument,crassinucellate ovules which were anatropous. In the late of May, megasporocyte came into being and turn into embryo sac that has seven cells and eight nucleus in a week or so. Fertilization process finished in the end of May. Betula platyhylla embryo became mature after the process of zygote, proembryo, globular embryo, heart stage embryo and torpedo stage embryo. Meanwhile fertilized polar nucleus went into mitosis in Nuclear type. Endosperm increased and grew walls until heart stage embryo formed.

关 键 词：白桦 雌花发育 大孢子发生 胚胎发育 解剖学 

分 类 号：S792.153[农业科学—林木遗传育种] Q944.4[农业科学—林学]