Molecular marker assisted screening for resistance against late blight and root knot nematode in tomato

Late blight and root-knot nematode (RKn) causes heavy yield losses to tomato in major parts of India including Punjab and thus affecting the sustainable crop production. Development of hybrids conferring resistance to late blight and RKn vis a vis good horticultural traits is the most economical and safe strategy to combat these pathogens. The Ph-2, Ph-3 genes from S. pimpinellifolium confer resistance to late blight and Mi-1.2 gene from S. peruvianum for RKn. Since physical resistance and validation for late blight and RKns is destructive, tedious and time consuming process, molecular markers linked to the specific resistance genes can be deployed to select genotypes having desirable genes. Therefore in the present study, CAPS marker (dTG63 and TG591) linked to Ph-2, Ph-3 gene, respectively and SCAR marker, (Mi-23) for Mi-1.2 gene was deployed to select the resistant genotypes and to investigate the result of used markers for further selection of genotypes for specific genes in resistance breeding proramme.