| Through three years filed investigation and laboratory determinations, the genetic variation was analyzed by the phenotypic character and SSR molecular marker of introgressed lines, the specific SSR loci from exogenous consanguinities was founded,the relationship between introgressed ingredients and phenotypic character of G..hirsutum was also analyzed.The main conclusions were as follows:1,The differences of phenotypic characters among different introgression lines indicated that the plant height, boll numbers, lint percentage, boll weight and boll open date showed very significant differences,and fiber length and fiber strength with significant differences. Tremendous variation with resistance to verticillium wilt in the filed was found amoung these lines, and the domestic lines showed better resistance to verticillium wilt than that of the abroad ones. There are extremely significant differences of yield characters within dual hybrid ortriple-hybrid introgressed lines, but with no difference between them.2,The clustering diagram results of the phenotypic character and SSR loci showed that the veracity of phenotypic character clustering was lower than that of SSR analysis, but also has certain guidances to selecting excellent germplasms for varirty improvement.3,There are 16 loci with high PIC (>0.80) in 87 pairs of polymorphism primers. 41 polymorphism pairs of primers distributed in 73 chromosomes except chromosome 5, 10, 12, 26, average two loci in each chromosome. These better polymorphism primers help to detect of the exotic components in the introgressed lines.4,By using genomic DNA of exogenic parents and standardard line of G.hirsutum TM-1 as check, we found 73 SSR specific loci, including 6 specific loci which were common loci among more than two wild species, 42 specific loci of exogenic wild species origined from EST-SSR. These results implied that these lines might been introgressed with wild exogenic components, even some elite fiber or resistance genes of wild species might be introduced into it.5,There was significant correlation between 13 SSR sepecific loci and the fiber quality, including 6 loci with very significance correlation.There was significant correlation between 19 SSR specific loci and agronomic characters, including 8 loci with very significant correlation. These loci might play important role to improve phenotypic characters of cotton.6,Introgressed components from G.arboreum were more than that of G.thurberi in the Thri-hybrid introgressed lines with the ratio of about 1:2 specific SSR loci . This revealed that exogenic components of G.arboreum L could stably consisted in G.hirsutum, and introgressed components of G.thurberi might be few.There were few exogenic specific SSR loci in introgressed lines of. G. bickii and G. anomalum.7,Only the number of SSR specific loci were founded significantly correlation with the fiber fineness of cotton amomg the thri-hybrid introgression lines with G.arboreum and G.thurberi and introgressed lines or the ditro-hybrid introgression lines with G.barbardense .It is showed that the more SSR specific loci may result in thinning of cotton fiber in the Thri-hybrid introgressed lines, the increased SSR specific loci in introgressed lines of the G.barbadence would quite the contrary. However, There is no significant correlation between their specific SSR loci of G.arboretum or G. thurberi and their fiber fineness.This indicated the common contribution of exotic G. arboretum and G. thurberi is needed for improving fiber fineness. Morever, only the moderate amount of introgressed components will improve the cotton fiber quality, too many imported components will cause poor fiber quality.
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