Mapping of a southern root-knot nematode resistance gene in pepper and marker-assisted selection

A southern root-knot nematode resistant inbred line 09C649 was crossed with a susceptible line 09C108.The F2 segregating population was obtained.Disease investigation and heredity analysis revealed that the resistance to southern root-knot nematode in 09C649 was controlled by a dominant gene,tentatively named as Me8.Two hundreds and thirty six pairs of SSR markers,1 pair of SCAR marker,1 pair of SSCP marker,8 pairs of EST-SSR markers and 2 pairs of COSII markers were used to map Me8.It was located on the chromosome 9 of pepper.The four molecular markers SSCP_B322,COS710,SCAR_315 and COS970,were the nearest markers away from Me8 with genetic distances of 0,0.1,1.3 and 3.3 cM respectively.Southern root-knot nematode resistance genes N,Me1,Me3 and Me7 were also located in this genomic region.These markers could thus be used in marker-assisted selection for all the southern root-knot nematode resistance genes that were found currently.The SCAR_315 was used in marker-assisted selection of 37 pepper lines.And the molecular identification was well in agreement with the southern root-knot nematode resistance tests.