Identification Of Regeneration Ability And Related Gene Using RIL Population Upland Cotton

Cotton is the main economic crop,nowadays,the traditional breeding method are often plagued by long years.With the rapid development of molecular biology,it is an inevitable trend to good genetically modified varieties by combining somatic embryo regeneration technology.Until now,only a few cotton varieties have the attributes of rapid and efficient regeneration,and most cultivars do not possess these attributes.In the process of somatic embryogenesis,there are many factors that affect the differentiation of embryogenesis and plant regeneration.The genotype of the donor and the type of culture medium are the most influential factors in somatic embryogenesis.It is possible to fine-map the loci controlling the embryogenic ability in cotton by the forward genetics strategy,the regeneration ability can be transferred varieties with low regeneration capacity,and the high quality cotton varieties with high regeneration capacity could be developed.In this study,a recombinant inbred population(RIL)has been developed and named as YE,which was derived from the cotton cultivar(YZ-1)that could quickly regenerate,and E22 is the main cultivars of the Yangtze river region.one hundred and sixty-four RILs were chose and cultured by the IBA+KT(IK)and 2,4-D+KT(DK).Statistical analysis was performed with the callus induction rate(CIF),callus secondary fecundity(CSC),embryo rate of callus(CRE)and callus embryo time(CET).The comparison analysis of the color texture and culture process were also evaluated in the two systems.The results are as follows:(1)The IK and DK systems were used for the regeneration of YE population.Combining with the statistical analysis about callus trans-generational fecundity,differentiation of embryonic callus time,differentiation rate,and the comparison of the color texture and culture process in the two system,the result showed that IK cultivation system was more suitable.(2)Based on the IK system,thirty-six renewable lines were obtained,thirty-five renewable lines were obtained in the DK system,and twenty-five lines in both systems,there were thirty-one broadleaf cotton lines,and the regeneration ability of sixteen lines were close to YZ-1 with good agronomic characters.(3)Based on the high density genetic map in our laboratory,four hundred and ninety-four markers covering the whole genome were selected with a genetic distance of10 c M.Five high regeneration capacity lines from each system were chose for whole-genome background detection.The YZ-1 alleles were identified in ten highly regenerative lines.The locus of the YZ-1 alleles were selected as the candidate loci for the genetic effect of controling regeneration.A total of twenty-five candidate loci for controling regeneration were screened on fifteen chromosomes.