Assessment of genetic diversity in annatto through progeny evaluation

Abstract

Annatto is a commercially exploited plant species for its seed dye. Bixin is the carotenoid present in the seed arils of the plant. Twenty seed based progenies were raised from plus trees of Bixa orellana L. collected from various geographic locations of Tamil Nadu and Telangana. Significant variations were recorded in the growth performance under nursery. Genetic divergence studies revealed that 20 progenies were resolved into seven clusters. Higher cluster mean values were shown in cluster VII (TNBi 0012) and cluster VI (TNBi 008), as they are unique and genetically divergent. The  clustering pattern revealed that there is no connection between genetic diversity and geographical nearness. Cluster IV reported maximum intra cluster distance. Maximum inter cluster distance was recorded between cluster I and cluster IV. The progenies of cluster I (TNBi 003  and TNBi 005) and cluster IV (TNBi 002  and TNBi 0013) could be employed for further hybridization for the improvement of the species.