矮沙冬青小孢子发生和雄配子体发育的观察

Microsporogenesis and the Development of Microgametophyte of Ammopiptanthus nanus

摘要:

对矮沙冬青（Ammopiptanthus nanus）小孢子发生及雄配子体发育过程进行了观察，结果表明：花约具4个花粉囊，花药壁发育为基本型，由表皮、药室内壁、中层（2—3层）和绒毡层组成，绒毡层为腺质型。小孢子母细胞减数分裂后胞质分裂为同时型，四分体为四面体型排列，成熟的花粉粒为二细胞型。在矮沙冬青小孢子发生及雄配子体发育过程中没有发现异常现象，认为矮沙冬青濒危不存在雄性生殖结构与发育过程异常的内在因素。

Abstract:

The anther of an endangered species, A mmopiptanthus nanus （M. Pop.） Cheng f., is tetrasporangiate. The anther wall is of basic type in the development, which comprises epidermis, fibrous endothecium, middle layer and glandular tapetum. The microspore mother cells undergo meiosis, and the cytokinesis is simultaneous. The tetrads are tetrahedral. Mature pollen grains are two-celled at the dispersal stage. The abnormal development is not found in microsporogenesis and in development of microgametophyte of the species. It is suggested that the endangerment of the species is not related to the microsporogenesis and microgametophyte development.