番茄受精作用及其间隔期的研究

The study of fertilization and duration of its different phase in Lycopersicum esculentum Mill.

利用常规石蜡切片法研究了番茄受精作用的全过程,具体研究结果为:(1)授粉后2h,花粉粒在柱头上萌发;约2～4h,花粉管长入柱头,且末端膨大;约8h后,生殖细胞进入分裂期;并于约两小时后,分裂为两个精细胞。(2)约14h,花粉管进入子房腔;约18～24h,花粉管进入胚囊,破坏一个助细胞,并在其珠孔端释放两个精子;随后被释放的精子移到卵细胞与次生核附近。(3)授粉后约30h精核进入卵细胞;约34h,精核与卵核融合,并在卵核内出现分散的雄性染色质,进而出现雄性核仁;44～50h,雌、雄性核仁融合,形成合子;合子的休眠期为10h左右。60h之后,合子分裂形成二细胞原胚。(4)约26h,另一个精子的精核与次生核核膜相贴伏,随后与之融合;约30～34h,次生核内出现分散的雄性染色质,随之出现雄性核仁;约38～42h,雌、雄性核仁融合,形成初生胚乳核。约44h后,初生胚乳核进行有丝分裂,形成两个胚乳细胞。番茄胚乳发育属于细胞型。初生胚乳核无休眠期。(5)精子与次生核的融合比与卵核的融合快。(6)番茄的受精作用属于有丝分裂前配子融合类型。

Observe the whole process of fertilization of Lycopersicum esculentum Mill. by means of paraffin wax. The main results are as follows： （ 1 ） In 2 hours after pollination, pollen grains germinate on the tissues of the stigma. In about 2 - 4 hours, pollen tubes enter the stigma with enlargement of the distal portion. In about 8 hours, the genital cell comes into division cycle. After 2 hours, the genital cell divides into 2 sperm cells. （2） In about 14 hours, the pollen tube enters the ovary. In about 18 -24 hours, the pollen tube enters the embryo sac and destroys one of the two synergids, releasing 2 sperms in the micropylar end. Then the 2 sperms move to the place between the egg cell and the secondary nucleus. （3） In about 30 hours after pollination, sperm nucleus enters the egg cell. In about 34 hours the egg nucleus and sperm nucleus begin fusing. In egg nucleus there is the male chromatin scattered, and then a small male nucleolus appears. In 40 -50 hours, male and female nucleoli are fusing, it means the formation of zygote. The dormancy stage of zygote is about 10 hours long. In 60 hours after pollination, zygote begins dividing into 2-cell proembryo. （4） In about 26 hours after pollination, the sperm nucleus of another sperm nestles on the nucleus membranes of the secondary nucleus, and then fuses with it. In about 30 -34 hours, it emerges male chromatin scattered, and a small male nucleolus appears. In about 38 -42 hours after pollination male and female nucleoli are fusing, it means the formation of primary endosperm nucleus. After 44 hours, the primary endosperm nucleus begins dividing, and then forms 2 endosperm cells. Accordingly, the development of endosperm in Lycopersicum esculentum Mill. belongs to the cellular type. There is no dormancy stage in the development of primary endosperm nucleus. （5） The fusion of sperm nucleus with the polar nucleus is faster than that with the egg cell. （6） Double fertilization is the type of the Premitotic gametogamy.