Comparative Assessment of RAPD and ISSR Markers to Study Genetic Polymorphism in Colletotrichum gloeosorioides Isolates of Mango

Background and Objective: Morphological traits of the genus Colletotrichum are extremely variable and hosts might be infected by a single or multiple species of the pathogen, hence development of species-specific primers has provided a powerful tool for the detection of plant pathogens.The objective of the study was to assess efficiency of Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeat (ISSR) primers against C. gloeosporioides in terms of genetic variability.Materials and Methods: Random amplified polymorphic DNA and inter simple sequence repeat primers are simple PCR-based assays targeting microsatellite regions of the genome.Intra and interspecific polymorphisms among the twentysix isolates of C. gloeosporioides, causing anthracnose on mango were evaluated by these markers.Results: In the present research, RAPD primers generated 519 amplicans with 82 alleles of which 77 were polymorphic with 7.4 assay efficiency index; ISSR markers produced 1469 amplicans with 189 amplification products, out of which 180 were polymorphic with 11.81 assay efficiency index.Although both the techniques were efficient and reproducible, ISSR indicated higher genetic variability in terms of percent polymorphism, polymorphism information content and effective multiplex ratio compared to RAPD analysis.Among 16 ISSR primers (CAG) 5 , (TGTC) 4 , (AGG) 5 , (TCC) 5 , (CAG) 3 , (AG) 8 T, (GA) 8 T, (TG) 8 A, (GA) 8 YG, (GT) 8 YC recorded highest percent polymorphism and highest PIC value of 0.97 by (GA) 8 T and EMR of 23.04 by (GACA) 4 was recorded.Conclusion: It is concluded that well-chosen ISSR primers could result in quick estimate in terms of their efficiency in detecting polymorphisms among the isolates.