Genetic diversity analysis of Indian Cassava (Manihot esculenta Crantz) accessions using morphological and molecular markers

Abstract

Thirty cassava accessions, including released and pre-release varieties in India were selected for morphological, statistical and molecular analysis to evaluate their genetic divergence. Based on ANOVA (Analysis of Variance), significant differences were observed in thirty genotypes for the fifteen characters used in the study. Most of the characters such as plant height, stem weight plant−1, number of leaves plant−1 and mean weight of tuber exhibited high GCV and PCV along with a positive correlation to tuber yield plant−1. Path analysis showed that stem weight plant−1, number of tubers plant−1, number of leaves plant−1, leaf dry matter content and number of nodes plant−1 directly affected tuber yield plant−1. The genotypes were then grouped into nine clusters following Mahalanobis’ D2 statistics with clusters IV and VIII recording the maximum inter-cluster distance, which gave an idea about the diversity prevailing among them. PCA analysis showed that stem girth, number of nodes and tuber yield plant−1 accounted for greater variability among the genotypes. Molecular analysis using SSR markers showed polymorphism for eighteen markers and molecular dendrogram clustering grouped the genotypes into three principal clusters with different subclusters. Overall, the study highlights the genomic diversity of cassava accessions and provides valuable insights into their characteristics and yield potential.