摘要
为确定红丁香在北京城区引种栽培条件下种子败育发生的时期,对其有性生殖过程进行了形态和胚胎发育解剖观察。授粉试验显示,北京市植物园引种栽培的红丁香人工自花授粉及去雄套袋授粉均未坐果,人工异花授粉坐果率为31.86%,天然授粉坐果率为8.32%,表明栽培条件下红丁香自交不育,传粉媒介不足导致坐果率低,但是各种授粉方式均未获得种子。胚胎发育过程解剖观察显示:红丁香花药壁发育为基本型,腺质绒毡层,胞质分裂为同时型,2-细胞成熟花粉;倒生胚珠,单珠被,薄珠心,胚囊发育为蓼型,核型胚乳,胚发育类型为紫菀型,先后形成球形胚、心形胚、鱼雷胚和子叶胚;但后期子叶胚发育停滞,其细胞逐渐降解,随后胚乳细胞也出现降解。可见,栽培条件下红丁香大小孢子及雌雄配子体发育、传粉受精过程、胚胎发育初期均正常,但后期胚、胚乳均发育停止,是红丁香引种栽培条件下种子败育的关键环节,其原因有待进一步研究。
To better understand the aborted seed of cultivated Syringa villosa in Beijing, morphological and anatomical characteristics on both anther and embryo development during the sexual reproductive stage had been observed. The fruit set from artificial self-pollination and controlled emasculation was 0 while artificial cross pollination and open pollination were 31.86% and 8.32% respectively. S. villosa was a self-sterile plant under cultivated conditions and no viable seed was harvested. Anatomical observations indicated that the anther wall conformed to the basic type and glandular tapetum. The cytokinesis of the microspore mother cells in meiosis was the simultaneous type. The mature pollen grains were of 2-celled type. The ovule was anatropous, unitegmic and tenuinucellate. The development of embryo sac was the polygonum type. The endosperm developed to be the nuclear type and the embryo the asterad type. The globular embryo, heart-shaped embryo, torpedo embryo and cotyledonal embryo were formed sequentially. But the development of cotyledonal embryo stopped and all ceils degraded gradually at later stages, then the endosperm cells were deteriorated. The results indicated that microspore and megaspore, male and female gametophytes, pollination fertilization and early embryo development were normal, but the later embryo and endosperm growth stopped. Further studies should address these issues.
出处
《北京林业大学学报》
CAS
CSCD
北大核心
2012年第6期107-114,共8页
Journal of Beijing Forestry University
基金
北京市科学技术委员会项目(D09050603770804)
关键词
红丁香
种子败育
解剖学
传粉受精
Syringa villosa
seed abortion
anatomy
pollination and fertilization
