RAPD-based Genetic Diversity and Relationship Analysis in Mango (Mangifera indica L.) Genotypes Grown under Heavy Rainfall Zone of South Gujarat, India

Abstract

Assessment of genetic diversity is essential for the effective conservation, characterisation and utilisation of mango (Mangifera indica L.) germplasm in breeding programmes. In the present study, genetic relationships among thirty mango genotypes, including Lal Mulgoba, Makaran, Neelum, Badami Model, Neeleshan, Banglora, Neelphonso, Kalipari, Sonpari, Alphonso, Baneshan, Ratna, Langra, Neeleswari, Sindhu, Sardar, Jamadar, Asadiyo, Dadmiyo, Amrapali, Dashehari, Mallika, Pari, Rajapuri, Fazri, Amrutam, Karanjiyo, Vashi Badami, Vanraj and Kesar, were investigated using random amplified polymorphic DNA (RAPD) markers. Genomic DNA was extracted from young leaf tissues using the CTAB method and assessed for quality and quantity by spectrophotometric analysis and agarose gel electrophoresis. RAPD amplification generated distinct and reproducible polymorphic banding patterns, which were scored in a binary matrix and subjected to genetic similarity and cluster analyses using NTSYSpc software. The RAPD markers revealed substantial genetic polymorphism among the studied genotypes, indicating considerable genetic variability within the germplasm collection. Pairwise similarity coefficients ranged from 0.3259 to 0.7860, with the highest genetic similarity observed between ‘Amrapali’ and ‘Dashehari’ (0.7860), suggesting a close genetic relationship, whereas the lowest similarity was detected between ‘Banglora’ and ‘Neelphonso’ (0.3259), reflecting marked genetic divergence. Cluster analysis further grouped the genotypes according to their genetic affinities, demonstrating the effectiveness of RAPD markers in discriminating closely related mango cultivars. The observed genetic diversity provides useful information for germplasm management, parent selection and the development of improved mango cultivars through targeted breeding strategies.