Genetic And Molecular Markers Of Fertility Restorer Genes In Cytoplasmic Male Sterile Line J-4A From Upland Cotton

Upland cotton accounts for over 90%of global cotton production and is an important economic crop in China.The heterosis of cotton is very significant,but the main use of hackney cotton cytoplasmic male sterile line.However,the hybrids prepared from the harkissima cytoplasmic male sterile line had cytoplasmic adverse effects,and the recovery lines were few,and there was a photo-temperature effect,and the pollen amount of the restorer line was insufficient under long day and high temperature conditions.Therefore,artificial detasseling is generally used to produce hybrid seeds in production.However,with the increase in labor costs,this method of artificial castration production of hybrid seeds has lost market prospects.Prof.Zhou Ruiyang and other authors used the Gossypium hirsutum strain J-4 as a receptor to obtain male sterility mutants by transposing the GhbZIP1 gene from upland cotton using the pollen tube pathway method,and selected cytoplasmic males for non-transgenic J-4 to be recurrent parents.In the breeding line J-4A,three restorer lines,H265,H267,and H268,were obtained using the test cross-selection method to achieve the three-line support.In this study,J-4A was used as the parent and H265,H267 and H268 were used as male parents to study the inheritance and molecular markers of restorer genes.The following main results were obtained:1 Genetic studies show that the restorer gene is a pair of dominant genes.Statistical analysis was performed on the BC1F1 and F2 groups of the constructed sports.Among the BC1F1 population,100 were fertile and 121 were sterile.The chi-square test met the 1:1 segregation ratio;F2 population was 54 fertile and 15 were fertile.Infertility,the chi-square test meets the 3:1 separation ratio.For the B1C1F1 and F2 generations,intra-group self-incrimination,sister-infant and CMS J-4A were backcrossed to identify descendants.The identification of descendants by chi-square test further verified that the genetic model of the J-4A fertility restorer line H265 was consistent with a single-gene dominant genetic model.At the same time H267 material also reached the same conclusion.At the same time,H267 material also reached the same conclusion;H268 backcrossed with the expected ratio of 1:1,and allele verification results found that H267 and H268 restore the gene allele.2 Using SSR markers,8 pairs of H267 restorer materials were initially found in the H265 restorer material and 7 pairs of primers were initially identified to identify sterile and fertile strains.A total of 165 pairs of primers were screened with fertile and sterilized pools constructed from two restorer lines of H268 and H267.It was found that TMB1629,BNL3535,TMB1295,BNL4047,BNL1231,JESPR218,BNL3627 and TMB0154 were in the H265 sterility pool and fertile pool showed polymorphism.TMB0313,BNL3535,BNL3627,TMB1346,JESPR-236,TMB0366,TMB0446 show polymorphism in H267 sterility pool and fertile poolThe results of this study laid the foundation for further study on the fine mapping and genetic expression of J-4A restorer genes.The results of this study laid the foundation for further study on the fine mapping and genetic expression of J-4A restorer genes.