赖草的染色体组型及非整倍体

在减数分裂研究的基础上对赖草染色体组型、非整倍体进行了调查研究。结果表明：赖草（Aneurolepidiumdasystachys）的染色体组型公式为2n＝4x＝28＝28m（4SAT）。但核仁染色体数目有一定的变异，调查了80株，其中70％含有二对核仁染色体，30％含有一对核仁染色体。赖草群体中非整倍体频率较高，调查了191株，其中2n＝28（整倍体）占6963％，超倍体占2．61％，亚倍体占27．76％。通过观察分析认为，产生非整倍体的主要细胞学原因是减数分裂前期Ⅰ不联会或联会消失以及减数分裂不分离。亦对赖草的非整倍体分离和利用进行了探讨。

The Karyotype of Aneurolepidium Dasystachys and Its Aneuploids

Study results showed that karyotype formula of 2n = 4 x= 28 = 29m(4SAT). But there are variable numbers of nucleolar chromosomes in this species.There are 70% plants with two pair nucleolar chromoomes and 30 % with one pair in the investigated 80 plants. There is a higher frequency of aneuploid in this species. we investigated 191plants, and among them there are 69. 63 % euploid (2n = 28 ), 2. 61 % hyperploid and 27. 76%hypoploid. The study revealed that asynapsis or desynapsis of meiosis in the prephase and undisjunction of merosis are the main cytologia causes in the occurrance of aneuploid. The selection anduse of aneuploid an A dasystachys were also discussed by this paper.