毛花猕猴桃(Actinidia eriantha Benth.)的染色体与花粉母细胞减数分裂的观察

毛花猕猴桃是雌雄异株植物,但雌株和雄株的花器结构,仍分别保留着雄性或雌性的退化器官。毛花猕猴桃的染色体数2n=58。无论雌花或雄花,花粉母细胞均能进行减数分裂。在第一次分裂的终变期或中期,有29个二价体。减数分裂的整个过程,染色体行为正常,但雌花的花粉最终则完全败育。花粉母细胞的减数分裂,是在雌雄花形态上分化之后才进行的,表明雌雄株花粉发育的差异,是由各个体的基因型所决定的。毛花猕猴桃各个植株的性别功能表现相当稳定,但性别的决定机制至今仍未搞清,深入研究其性别决定的机制,在学术上和育种实践上均有重要意义。

OBSERVATION ON THE CHROMOSOME AND MEIOSES OF POLLEN MOTHER CELLS IN “MAOHUA-GOOSEBERRY”(ACTINIDIA ERIANTHA BENTH.)

“Maohua-Gooseberry” (Actinidia eriantha Benth.) is a dioecious plant. The remnant of the hermaphroditic organ is still kept inside the flower, with undeveloped pistil in the male flower and undeveloped stamen in the female flower The chromosome numbers of 2n=58. The meioses of pollen mother cells proceed disregard of either male or female flower.At diakinesis or metaphase in the first division of meioses,29 divalents appeared.Throughout the process of meioses,the chromosomal behavior exhibit regular,but the pollens are completely sterile in the female flowers. The meioses of pollen mother cells proceeds after the morphological differentiation of the male and female flowers.Developmantai differences between male and female sexes are under the genotypic control of the plant. The function of sexual differentiation is quite stable.While the mechanism in sex determination remains as a problem to be studied further.Such is a problem of interest in theoretical as well as practical breeding.