同源四倍体珍珠粟的育性和减数分裂染色体行为。

Fertility and meiotic chromosome behaviour in autotetraploid pearl millet.

机构信息

Department of Botany, Andhra University, Waltair, India.

出版信息

Theor Appl Genet. 1982 Dec;62(4):345-51. doi: 10.1007/BF00275100.

Abstract

Tetraploidy was induced in outbred pearl millet and selection for high and low seed set was started in the C1 generation. Segregation in the C3 generation was observed for fertility and also for meiotic features: per cent seed set in selfed earhead, chiasma frequency, chromosome association and chromosome distribution in pollen mother cells were all affected. However, variation in seed set was observed even between samples not differing in meiotic features. It is apparent that factors regulating seed set in autotetraploid pearl millet were genic as well as chromosomal.A high frequency of univalents and trivalents was the main cause of sterility; quadrivalent misdisjunction was not a significant factor. As univalency decreased with increased chiasma formation, the gain was in the form of quadrivalents. However, individuals not differing in chiasma frequency did differ in chromosome association frequencies, indicating that the dependence of chromosome pairing behaviour on chiasmata was subject to genotypic influence.

摘要

在外群体的珍珠粟中诱导四倍体，在 C1 代开始进行高和低结实率的选择。在 C3 代观察到了育性和减数分裂特征的分离：自交穗结实率、交叉频率、花粉母细胞中的染色体联合和染色体分布都受到了影响。然而，即使在减数分裂特征没有差异的样本之间，也观察到了结实率的变化。显然，调节自交四倍体珍珠粟结实率的因素既有基因的也有染色体的。单价体和三价体的高频率是不育的主要原因；四价体错误分离不是一个重要因素。随着交叉形成频率的增加，单价体减少，四价体增加。然而，在交叉频率没有差异的个体中，染色体联合频率确实存在差异，这表明染色体配对行为对交叉的依赖性受到基因型的影响。