Genetic Diversity Analysis among Papaya (Carica papaya L.) Varieties using RAPD Markers

Papaya is one of the most important nutritional and medicinal fruit crops in the world. In this context, present study was aimed to analyse genetic diversity of 12 dioecious and gynodioecious varieties of papaya using 42 randomly amplified polymorphic DNA (RAPD) primers. Out of these 42 primers, 33 primers amplified 150 polymorphic bands with an average 4.54 polymorphic bands/primer. These 150 markers were used for estimation of Jaccard similarity coefficient which was in the range of 0.355 to 0.733. Two varieties namely Honey dew and Majestic showed highest similarity (0.733), followed by Surya and Vinayak (0.687) while Majestic and Mohini showed least similarity (0.355), followed by Ajeet and Mohini (0.381). This similarity matrix was used for cluster analysis using software Free Tree. In the UPGMA based dendrogram four distinct clusters were obtained in which one variety Mohini showed highest diversity with other varieties of papaya. Results of principal components analysis (PCA) was similar to that obtained by UPGMA clustering. Genetic diversity analysis obtained by these two methods showed that papaya cultivars and hybrids possess narrow level of genetic diversity.