Submitted to: Atlas Journal of Plant Biology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 2/24/2014
Publication Date: 4/4/2014
Citation: Abdelmajid, K.M., Ramos, L., Hyten, D.L., Kantartzi, S., Bond, J., Grier, R.L., Bendahmane, A., Arelli, P.R., Cianzio, S., Meksem, K. 2014. Quantitative Trait Loci (QTL) that Underlie SCN Resistance in the Soybean [Glycine max (L.) Merr.] ‘PI438489B’ by ‘Hamilton’ Recombinant Inbred Line Population. Atlas Journal of Plant Biology. 1(3):29-38. Interpretive Summary: Soybeans are susceptible to many diseases including nematode diseases such as soybean cyst nematode (SCN) which can greatly reduce yields. One method of decreasing the amount of SCN that occurs in soybean production is to discover and incorporate new resistant genes into elite cultivars that are currently being developed by soybean breeders. We used 648 DNA markers to discover eight regions in the soybean genome that likely contain resistant genes to SCN. These resistant genes were shown to decrease the level of nematodes that grow in the roots. This information will be used by public soybean breeders and private seed companies to increase the efficiency of incorporating these resistant genes into new soybean cultivars to increase soybean resistance to SCN.
Technical Abstract: Soybean cyst nematode caused by Heterodera glycines is the most devastating pest in soybean [Glycine max (L.) Merr.]. Resistance to SCN is complex, polygenic, race-cultivar specific, and controlled by several QTL. Our objective was to identify and map QTL for SCN resistance to races 3 and 5 using a high density SNP-based genetic linkage map based on the ‘PI438489B’ by ‘Hamilton’ (PIxH, n=50) recombinant inbred line population. The PI438489B by Hamilton map contained 648 SNPs distributed on 31 LGs with a coverage of 1,524.7 cM and an average distance of 2.35 cM between two markers. Using interval mapping (IM) and composite interval mapping (CIM), eight QTL were identified for SCN resistance to races 3 and 5 on 7 different soybean chromosomes. Four QTL for resistance to SCN race 3 were identified and mapped on chromosomes 7, 13, 15, and 16. Similarly, four QTL for resistance to SCN race 5 were identified and mapped on chromosomes 5, 8, and 11. Chromosome 8 contains a cluster of SCN and sudden death syndrome (SDS) resistance QTL. A total of five QTL were identified on this chromosome: two for SCN resistance and three for SDS resistance. The QTL identified here maybe introduced in breeding programs to develop cultivars with dual resistance to SDS and SCN.