Genetic Diversity Assessment of Off-season Jackfruit (Artocarpus heterophyllus Lam.)

Abstract

This study evaluates the genetic diversity of 30 off-season jackfruit (Artocarpus heterophyllus Lam.) accessions collected from the northern districts of Kerala (Kannur, Kozhikode, and Malappuram) using SSR and ISSR molecular markers. A total of 20 SSR and 10 ISSR markers were employed to characterize the accessions. All ISSR primers exhibited polymorphism, with Polymorphism Information Content (PIC) values ranging from 0.02 to 0.29, whereas 16 out of 20 SSR primers were polymorphic, displaying PIC values between 0.08 and 0.47. Cluster analysis grouped the accessions into two major clusters and four subclusters, with the closest genetic relationship observed between KNR 3 and KNR 7. Principal Coordinate Analysis (PCoA) further supported the presence of distinct genetic groupings, particularly across two districts. Population structure analysis also revealed two major clusters with four subclusters showing varying levels of admixture. Overall, the findings indicate moderate genetic differentiation among the accessions, likely reflecting common ancestry and restricted gene flow due to limited seed dispersal and the geographic proximity of the collection sites.