ANALYSIS OF GENETIC DIVERSITY AND RELATEDNESS AMONG CULTIVATED AND WILD MULBERRY CULTIVARS/ACCESSIONS USING RAPD MARKERS

Mulberry with cosmopolitan distribution has a great economic value. The genetic diversity in mulberry, identified based on morphological characters, is highly ambiguous due to remarkable morphological plasticity. Molecular markers are meritoriously employed to identify genetic diversity and relatedness in living organisms. This study was conducted using six RAPD primers to decipher genetic diversity and relatedness among 18 mulberry accessions including 13 indigenous, four cultivated and nine wilds, and five overseas cultivated. Altogether 112 distinct bands were obtained, ranging from 270 to 600 base pair. Seventy-six bands (67.86%) were polymorphic (x = 12.67 primer -1). Five primers yielded > 0.5 polymorphic information content. All accessions were genetically different with genetic similarity coefficient varying from 0.364 to 0.933. The accessions were divided into four principal clusters with genetic distance of 41.6% to 92.3%. Genetic diversity was greater relatively in cultivated accessions compared to wild ones. Tropical and subtropical ecotypes were richer in mulberry genetic resources compared to temperate ecotypes. The cluster analysis unraveled a mixed genetic relatedness in cultivated and wild accessions. Accessions in temperate ecotype were concentrated in one cluster, while accessions in tropical and subtropical were concentrated broadly in two clusters. CMP-16 (cultivated) and STP-18 (wild) were genetically faraway from each other. PFI-1 (cultivated) and OKP-18 (wild) were related distantly with overseas accessions MLJ-85 (Japanese origin) and HSC-85 (Chinese origin), respectively. Based on these findings, it is recommended that above mentioned four indigenous accessions may be conserved in their respective ecotypes for future breeding programmes.