玉米A型不育系归群问题的初探

PRELIMINARY STUDY ON POPUIATION CLASSIFICATION OF A CYTOPLASMIC MALE STERILE LINE IN CORN

为了将玉米A型胞质不育准确归群,从分析A型不育系育性基因型入手,结合恢复性的遗传和小斑病的自然感染进行综合研究。采用启行设计的A型与T、S、C三类群的不育系(保持系)的互测杂交试验,初证出A型不育系的育性基因位点及对数;并用多型恢复进行辅助签定;14个自交系与A型不育系的杂交F_2代育性反应分别呈3∶1和9∶7,符合T型恢复性的遗传规律;最后再结合A型细胞质受小斑病感染的事实,初步将A型归入T群,试验结果表明,通过明确育性基因互位点上,有助于分析特定自交系测交育性反应的疑异和胞质不育的分类。

In order to classify populaion accurately, A cytoplasmic male sterile line in corn was comprehensively studied by analysis of its fertility genotype, along with restoring inheritance and natural infection of small dotted fungi. Fertility gene sites and pairs of A sterile line were primarily testified through reciprocal crossing test on A-type designed by ourselves with the sterile lines (mai ntai nance line) of three populations (T, S,C ) . After supplementary identifica lion by applying polytype restoring line, it was found that F2fertili- ty of 14 self-cross lines crossed with A was 3 (fertile ) : 1 (sterile) and 9 : 7 respectively, conforming to genetic laws of T restorer property. At the same time, based on the fact that A cytoplasmic sterile line was infected by mall dotted fungi, A was rudimentarily classfiied into T-population. The result denoted that deteimination of fer-tility gene interactive sites helped to analyse test-cross fertility action of the selt-cross line and classification of cytoplasmic male sterile line.