Phenotypic diversity, heritability, and association of characters in sugarcane genotypes at Metehara Sugar Estate, Ethiopia

ABSTRACT Genetic improvement of sugarcane (Saccharum spp. hybrids) yield is crucial in the improvement of crop productivity. This study was conducted with the objectives to estimate the degree of phenotypic diversity, heritability, and association of various traits and recommend sugarcane genotypes for commercial production and small-scale farmers. Fifteen sugarcane genotypes and one standard check variety were evaluated in plant, first and second ratoon crops for 14 quantitative traits including stalk and juice quality. Highly significant (p ≤ 0.01) differences among the genotypes for all the traits were observed. Phenotypic diversity of genotypes by principal component analysis (PCA) and cluster analysis indicated genetically diverse genotypes from divergent cluster groups, which can be exploited as desirable parents to use in hybridization programs. All traits had low to high correlations (r = 0.132 to 0.719) with cane yield. High broad-sense heritability (h2) was detected for single cane weight (82.55), number of millable canes (76.85), plant height (76.79), stalk diameter (73.22), and internode length (73.69) indicating that these traits could be selected for easily. Highest expected genetic gains were recorded in single cane weight (30.12) and number of millable canes (28.6). Path coefficient analysis of cane yield revealed that single cane weight and number of millable canes were the major contributors to cane yield. Results showed that millable cane number and single cane weight can be used as reliable selection criteria to improve sugarcane yield. Genotypes FG03104, FG05414, and FG05300 can be considered for commercial production at Metehara Sugar Estate and similar agroecologies.