摘要
山茱萸的花芽发育可以分为分化初期、小花原基突起期、花萼形成期、花冠形成期,雄蕊形成期、雌蕊形成期和花盘形成期等七个时期。在杭州地区,山茱萸的花芽于4月底开始分化;6月初形成小花原基突起;6月10日左右形成萼片原基;6月20日左右开始有花瓣原基突起;7月10日左右出现雄蕊原基;7月20日左右形成雌蕊原基;9月5日左右花盘原基形成:9月20日左右,大、小孢子母细胞进行减数分裂:11月初,雌、雄配子体发育成熟;次年3月开花。成熟花粉为2-细胞型,具3孔沟。子房1室,具1枚倒生胚珠,悬垂胎座,胚珠具单珠被、薄珠心。成熟胚囊为八核7细胞,在1月12日左右,反足细胞解体,2个极核融合为次生核,雌配子体仅剩下4个细胞组成,在胚珠发育过程中有珠被绒毡层、承珠盘和珠孔塞形成。花器官表面的表皮毛为平贴丁字毛。
The development of the floral bud in Cornus officinalis can be divi-ded into seven phases, i. e. the early differentiation phase, the floralprimordium projection, the calyx formation, the corolla formation, thestamen formation, the pistil formation and the floral disc formation. The floral bud begins to differentiate in Hangzhou area at the endof April. The floral primordium is formed at the early June, the sepalprimordium on June 10, the petal primordium on June 20, the stamenprimordium on July 10, the pistil primordium on July 20 and the floral disc primordium is formed on September 5. The meiosis of both mega-spore mother cell and microspore mother cell is taken place on Septem-ber 20. By the beginning of November the female gametophyte andmale gametophyte both reach their maturation. The flowers are out inthe following March. The mature pollen grains are 2-celled, 3-colpo-rate. The ovary is generally 1-celled that contain one pendulous,anatropous ovule, which is unitegminous and tenuinucellate. The ma-ture embryo sac consists of seven cells that contain eight nuclei. Byfollowing January 12, three antipodal cells degenerate, two polar nucleifuse into the secondary nucleus, and so that the female gametophyte isonly composed of four cells. Some special structure, e. g. integumen-tary tapetum, hypostase and obturator are formed during the develop-ment of ovule. In addition, the epidermal hair on the scale, the bract,the pedicel and the receptacle is flat T-shaped hair.
出处
《西北植物学报》
CAS
CSCD
北大核心
1991年第3期234-242,共9页
Acta Botanica Boreali-Occidentalia Sinica
基金
国家自然科学基金
关键词
山茱萸
花
发育解剖学
Cornus officinalis
Flower
Developmental anatomy
