| Mungbean [Vigna radiata (L.) Wilczek] is an important legume crop in China, which serve theirroles as cash crops for farmers and as protein sources for consumers. It is a traditional crop in China andhas a long history of cultivation. China is the number one export country of mungbean in the world.Bruchid (Callosobruchus spp.) is a serious pest during storage of seeds of mungbean and other Vignaspecies. Breeding for bruchid-resistance is a major goal in mungbean improvement. In order to set upthe foundation of the molecular marker assisted breeding of bruchid-resistance and molecular designbreeding, we need to initiate the construction of a high-density genetic linkage map, genetic research ofobjective traits and gene location. At present, SSR markers for genetic analysis of these legumes aremuch limited. Transferability analysis of primers has the vital significance to reduce their developmentcost and improve their development efficiency. In this study, we evaluated the transferability ofmungbean Genomic-SSR markers in other Vigna species and constructed a high-density genetic linkagemap of mungbean using SSR and STS markers we developed. The bruchid-resistance gene Br1we finemapped using a Recombine-inbred-lines (RIL) population from the cross between Berken and ACC41.We analyzed the QTLs for Plant height, Number of nod, Pod length, Pod width, Seed per pod and100-seed weight yield-related traits. The results are as follow:1.1205SSRs primers were tested for their transferability and polymorphism by PCRamplification with the genomic DNA of four Vigna species, cowpea, adzuki bean, mungbean and ricebean. The results indicated that the transferability rate of mungbean genomic-SSR in cowpea, adzukibean and rice bean was50.0%,73.3%, and81.6%, and the ratio of polymorphism SSR primers in thesecrops was4.1%,1.7%, and1.5%, whereas32.0%in mungbean. A total of469mungbean genomic-SSRprimers were detected to be highly transferable among different species of Vigna. The transferability ofmungbean genomic-SSR was higher in adzuki bean and rice bean than in cowpea. These transferablemarkers are useful for further genetic and breeding studies in these species.2. A molecular genetic map of mungbean was constructed with a190F10recombinant inbred linepopulation from a cross of a highly bruchid-susceptible cultivar Berken and a highly bruchid-resistancewild mungbean ACC41, by using SSR, STS, RFLP and RAPD markers. The total length of the map,which comprised11linkage groups, spanned735cM with an average distance between markers of1.75cM and a maximum distance between linked markers of9.7cM. The new genetic linkage map wasconstructed with419genetic markers(included333SSR markers,74RFLP markers,9STS markers and3RAPD markers). The lengths of the linkage groups ranged from17.5cM to120.3cM, and the numberof loci varied from9to76per linkage group. This genetic map is fundamental to gene localization，comparative genomics and QTL mapping of important agronomic traits.3. Bruchid-resistant locus Br1was mapped to a2.6cM segment between two SSR markers onlinkage group9. Two markers P2-627and C220are closest to the bruchid-resistence gene,approximately1.3cM away. 4. A total of62QTLs were identified for yield-related traits under the4environments.Contribution of single QTL to phenotypic variation varied from2.89%to30.19%．Of these，7QTLswere common under2or more than2environments．21QTLs were up to10%of the phenotypicvariation．... |
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