Genetic Effect Of The Introgressed Segments In The Introgression Line From Gossypium Hirsutum×gossypium Barbadense

Cotton fiber is the best raw material in textile industry, with the improvement of people’s living standard and the rapid development of textile industry, more and more important to Improve the quality of the fiber. In this study, F2 segregating population were derived from the combination of Chromosome Segment Substitution Line MBI9915 with high quality of fiber and CCRI36 which is recurrent parent. 347 F2:3lines were selected from F2 population. QTL mapping and interaction research were carried out in F2 and F2:3 population to research genetic effects of introgressive segments.Phenotypic analysis of fiber yield and quality traits in parents and populations were conducted. MBI9915 has high fiber quality with the fiber length more than 30 mm and fiber strength more than 33 cN·tex-1 in three years. The fiber length is more than 30 mm and fiber strength is more than 33 cN·tex-1 in F2 and F2:3 population too.The The transgressive rate over the recurrent parent CCRI36 for fiber elongation were 3.38% in F2 population, The transgressive rate over the recurrent parent CCRI36 for other traits were 27.09%-93.94%. The Coefficient of Variation of yield and quality traits in F2 population were 1.43%-16.95%.2292SSR markers covering the whole genome of cotton evenly distributed on 26 chromosomes have been genotyped for the parent. The genotype analysis showed that the recovery rate for MBI9915 was 97.30%, with a total 105.5cM distributed in 12 sea-island cotton introgression segments. The average recovery rate in F2 population was 98.4%, the largest was 99.6%,the least value was 97.9%;The average length of introgression segments was 81.74 cM, the largest was 107.42 cM,the least value was 20.46 cM.Total of 59 QTLs were identified by the software Icimapping in two generation., Among them 12 QTLs for yield traits traits including 5 for plant high,1 for fruit branch,4 for lint percent and 2 for boll weight, explaining 0.90%~9.51% of phenotypic variation respectively;And 24 QTLs for fiber quality traits including 5 for fiber length, 9 for fiber length,4 for Micronaire,4 for fiber elongationan and 2 for fiber uniformity were identified.7QTLs(qBW-20-1、qFL-5-1、qFL-7-1、qFU-5-1、qFM-8-1、qFS-20-1 and qFS-20-3) can be identified in two generation.Interaction about fiber length and fiber strength were researched by sofrware Icimapping. 13 pairs of interaction about fiber length and 13 pairs of interaction about fiber strength were identified in two generation. Among them, 3 pairs of interaction(Seg-7-1with Seg-8-1, Seg-8-1 with Seg-20-2, Seg-20-2 with Seg-20-3)about fiber length and 3 pairs of interaction(Seg-5-1 with Seg-20-2, Seg-7-1 with Seg-8-1, Seg-7-1 with Seg-15-1) about fiber strength can be identified in all generation.4 pairs of interaction(Seg-5-1 with area around 165 cM on Seg-20-2, Seg-7-1 with Seg-8-1, Seg-7-1 with Seg-15-1, Seg-7-1 with Seg-15-1)were tested affect fiber length and fiber strength together.Genetic effects of introgressive segments were analyzed through QTL mapping and interaction research and excellent chromosome introgression materials were selected. It’s laid a foundation for QTL fine mapping and clone.