Reevaluation of the Nematode Resistance In the M-120 RNR by Pima S6 Population

The objective of this study was to identify DNA markers linked to genes conditioning resistance to RKN in the resistant line M-120 RNR using newly developed SSR markers. In addition to the major locus on Chromosome 11, we have also identified a major QTL for total eggs and eggs/g of root phenotypes on chromosome 14. Combined across the two populations, the QTL had a LOD score of 9.462 and accounted for 31.90% of the variation in total eggs. The M-120 RNR allele in the root-knot nematode resistance locus on chromosome 14 is likely to have originated from Wild Mexican Jack Jones. Therefore, for the Auburn resistance source and its derivatives, our data also suggest that there are two genes control the root-knot nematode resistance in M-120 RNR.