GENETIC VARIABILITY AND ASSOCIATION OF TRAITS IN LENTIL (Lens culinaris Medikus) GENOTYPES FOR YIELD, YIELD RELATED AND NUTRITIONAL QUALITY TRAITS IN NORTH SHOA, ETHIOPIA

Abstract

Lentil is a multipurpose crop grown in many environments of Ethiopia and it is the second center of diversity in the country. However, limited information on genetic variation as well as the association of yield, yield related and nutritional traits is available. Therefore, this study was carried out to assess the genetic variability, traits association, direct and indirect effects of yield related and nutritional traits on grain yield of lentil genotypes. A total of 64 lentil genotypes were evaluated for 16 morpho-agronomic and qualitative traits in 8 x 8 simple lattice design at Debre Berhan Agricultural Research Center in 2018. The analysis of variance showed significant differences among the genotypes for all characters, indicating the existence of variability and potential for selection of the genotypes for desirable traits. Phenotypic (PCV) and genotypic (GCV) coefficient of variations ranged from 7.46 to 45.38% and 5.76 to 44.3%, respectively, in which the lower and higher PCV and GCV values were estimated for day to maturity and iron concentration of seeds, respectively. Heritability in broad sense ranged from 25.8% for grain filling period to 96.6% for seed yield ha 1 and genetic advance as percent of mean ranges from 7.63% for days to maturity to 89.19% for iron concentration of seeds. High heritability with high genetic advance was observed for seed yield, ash, iron concentration of seeds, above ground biomass, days to 50% flowering and number of seed per pod. Plant height, harvest index, number of pods per plant and protein had high heritability and moderate genetic advance. Seed yield showed positive and significant correlations with above ground biomass, number of seed per pods, number of pods per plant, plant height, harvest index, secondary branches and protein content of seeds at both phenotypic and genotypic level. Above ground biomass, harvest index, secondary branches per plant, plant height, number of pods per plant and protein content exerted positive direct effects on yield at phenotypic and genotypic level. This suggested the traits could be used for indirect selection of genotypes for yield. The genetic distance of genotypes estimated using Euclidean distance ranged from 3.14 to 10.32 with the mean, standard deviation and coefficient of variation of 5.30, 1.82 and 34.26, respectively. Principal component analysis showed the first four principal component (PC) axes; PC1 (34.7%), PC2 (11.2%), PC3 (8.91%) and PC4 (8.66%) accounted 61.67% of the total variation. The Dendrogram constructed using Unweighted Pair-group method with arithmetic means separated genotypes into 14 distinct clusters of which, Cluster IV and cluster IX to XIV were the largest clusters consisted of 42.91% genotypes and one genotype each, respectively. Inter cluster distances were highly significant (P<0.01) except between cluster II and VIII; and cluster V and VIII. The study results showed the presence of variations among genotypes with a wide range of genetic distances for morpho-agronomic and nutritional quality traits that could be utilized to develop varieties through selection and hybridization.