A preliminary analysis of the genetic control of male fertility in YS-type thermo-sensitive male sterile wheat lines.

Thermo-sensitive male-sterile wheat lines are the basic materials for the utilization of wheat heterosis using two lines.Revealing the genetic basis of the fertility control in thermo-sensitive male sterile wheat lines will promote the breeding of thermo-sensitive male sterile wheat lines,selection of cross combination with elite performance,and heterosis utilization in wheat production.In this study,two F2 populations were constructed using the YS-type thermo-sensitive male sterile wheat lines of A731 and A732-1 crossed with the restorer line China Spring,the male fertilities of the P1,F1,P2 and F2 under male sterile condition and the regenerated F2 population under male fertile condition of the two crosses were investigated,and subjected to analyze the genetic control of male fertility in YS-type thermo-sensitive male sterile wheat lines under male sterile and fertile conditions by applying the 4 generation method of P1,F1,P2 and F2 and the single F2 generation method of major gene plus polygene mixed inheritance model,respectively.The results showed that under male sterile condition,the male fertility of YS-type thermo-sensitive male-sterile wheat lines were controlled by two major genes and polygene,the heritability of major genes was 56.73%～71.20%,the heritability of polygene was 27.65%～41.20%;and under male fertile condition,the male fertility of YS-type thermo-sensitive male-sterile wheat line A731 was controlled by two major additive-dominant genes,that of A732-1 was controlled by two major additive-dominant-epitasis genes,the heritability of major genes was over 58.41%.It suggested the male fertility of YS-type thermo-sensitive male sterile wheat lines was controlled by two major genes plus polygene and the heritability of major genes were higher.