Intra- and interspecific genetic diversity exploration in chilli (Capsicum spp) using morphological and randomly applied polymorphic DNA markers

Abstract

An experiment was conducted to study intra- and inter-specific genetic diversity during the winter season of 2001 and 2002 in 33 chilli (Capsicum spp) accessions of North-Eastern India belonging to 3 species using morphological charteristic and randomly amplified polymorphic DNA (RAPD) markers. Forty Capsicum descriptor-bascd characters were used for morphology based hierarchical cluster analysis, which delineated 2 major clusters. One of the cluster included all but 1 C. annuum L. accession, while the other had all the C. chinese Jacq. and C.,frutescens L. accessions. However, accessions belonging to later 2 species were separated at sub-cluster level. For RAPD analysis, 20 random oligonucleotide primers were used and only 15 showed amplification. A total of 10l bands with a mean of 6.73 bands/primer were amplified in the test accessions out of which 81 were polymorphic. The fragment size ranged from 325 to 1436 bp. The RAPD markers detected 83.17% polymorphism among the accessions. Two distinct clusters were delincated here too with all the C. frutescens accessions in one and C. annuum and C, chinese accessions in another. However, the C. chinese accessions were separated from C. annuum at sub-cluster level. Thus, the accession belonging to 3 species were differentiated by this technique and the clusters corresponded to previous morphology based classification of the species. Cultivar specific RAPD markers for eleven accessions were also detectcd in the study.