DNA BASED GENETIC VARIATION FOR RED ROT RESISTANCE IN SUGARCANE

Genetic difference between twelve red rot resistant and five susceptible genotypes of sugarcane cultivated in Pakistan were studied using Random Amplified Polymorphic DNA (RAPD) markers. Initial screening was done using 300 markers and four genotypes (two resistant and two susceptible for red-rot). From these 300 markers, 24 were selected and further applied to all 17 genotypes. A total number of 182 loci were generated by these 24 primers. Of these 156 loci were polymorphic and 26 were monomorphic, whereas 10 loci were genotype specific, Moreover, the number of monomorphic loci for the resistant and susceptible genotypes was 29 and 52 respectively, However, none of the loci could be solely linked to either resistance or susceptibility against red-rot. The mean genetic similarity among the genotypes recorded was 74.37% which shows that a large part of the genome is similar. This may be due to the lack of parental diversity. This study reveals that there is possibly more than one genetic reason for resistance or susceptibility against red rot in sugarcane genotypes of Pakistan.