Abstract:

In order to clarify the genetic law of cotton genetic male sterile line discovered from the offspring population of a genetically modified cotton population in 1998, phenotype observation, classical self hybridyzation and sib-cross means were applied to analyze the flower phenotypic characteristics, genetic model, and the allelism for Yu 98-8A line. Floral morphology investigation showed that, the length of style and exposed style of sterile plants were significantly higher than the normal of fertile plants, while the diameter of ovary and the number of anthers of each flower had no significant difference. Pollen fertility examination results showed that, there was no pollen within the anther of sterile plants. Genetic analysis of hybrid offspring population of sterile and heterozygous fertile plants and the self-fertile of fertile heterozygous plants showed that, the male sterility was controlled by a single recessive gene. The progenies of F1 from Yu98-8A crossed with Lang A (msc1) and Dong A (msc3) were complete fertile. Several of the F2 populations derived from the F1 plants of Yu98-8A crossed with Lang A or Dong A showed fertility segregating with the ratio of sterile plants to fertile plants of 1:3, and the rest F2 populations showed 7:9. Those results suggested that, Yu98-8A male sterile gene was different from that of Lang A and Dong A.