Genetic Analysis Of Maize Doubled Haploid Population And Primary Study On QTLs

With two maize haploid populations and one DH population, 15 agronomic traits of DH population were analyzed hereditary. Segregation of three populations were detected by SSR. Genetic map of DH population was constructed. QTLs were identified for some traits of DH population. The results were summarized as follows:1. With maize DH population derived from "Nong Dan No.5" (Nongxi531 X Nongxi 110) induced by parthenogenetic inducing-line, the heritability analysis of 15 quantitation traits, i.e. ear length, ear perimeter, ear weight, cob perimeter, cob weight, 100-lernel weight, row No., kernel/row, rare ear length, plant height, stem perimeter, LUP, LUN, number of lateral branch, days from sowing to blooming, were made. The number of gene pairs controlling these traits was estimated. Based on kourtosis and skewness values of DH population, the gene interaction in these traits was discussed. The results showed that, complementary interaction was detected for rare ear length, days from sowing to blooming, row No. and cob weight. While the genie interaction was found absent for other traits. It was suggested that, ear length, ear perimeter, 100-lernel weight and plant height are selected in early generations because of high heritability, few gene pairs and absence of gene interaction.2. SSR makers were detected, with two maize haploid populations—"Denghai No.9"(8723 X 65232) and (Nongxi 531×K36), and DH population (con- taining 72 lines) derived from "Nong Dan No.5" (Nongxi 531× Nongxi 110) induced by parthenogenetic inducing-line. The results showed that, there was no segregation distortion among 30 markers of "Denghai No.9"and 24 markers of (Nongxi 531× K36). While 3 linked markers, locating the second chromosome, showed the segregation distortion(P<0.05) and derived toward female parent(Nongxi 531) among 39 markers of DH population.3. 72 lines of DH population derived from "Nong Dan No.5" (Nongxi 531×Nongxi 110) were evaluated for ear length, ear perimeter, ear weight, cob perimeter, cob weight, 100-lernel weight, row No., kernel/row, rare ear length, plant height, stem perimeter, LUP, LUN, number of lateral branch, days from sowing to blooming. With the interval mapping procedure, 8 QTLs were identified for plant height (2 QTLs), cob perimeter (1 QTL), ear...