Genetic variability study and path coefficient analysis in African eggplant ( Solanum aethiopicum L.)
Genetically improved African eggplant is needed for the exploitation of its potential for commercial use. Heritability and knowledge of correlation among agronomic traits help plant breeders decide which selection methods will be effective in crop improvement. Ten genotypes were grown at the research farm of NIHORT in July, 2014, using Randomized Complete Block Design in three replications, to determine the extent of genetic variability, strength of association and level of heritability among nine agronomic traits. Estimates of phenotypic and genotypic coefficient of variance, broad sense heritability, genetic advance, phenotypic and genotypic correlation coefficients were computed. Number of leaves per plant had the highest genotypic variance (253.98), while number of leaves per plant had the highest phenotypic variance (281.06). Number of leaves per plant, days to 50% flowering and fruit weight per plant showed high genotypic and phenotypic variance indicating that the genotype could be reflected by the phenotype and selection based on the phenotype performance of these traits could be effective. High heritability and high genetic advance observed in days to 50% flowering, stem girth, number of leaves per plant and fruit weight per plant revealed the preponderance of additive gene action which shows that selection for these characters could be effective. At genotypic level, fruit diameter had the highest direct effect on fruit weight per plant, while at phenotypic level; fruit length had the highest direct effect on fruit weight per plant. These two characters can be used as selection index for fruit weight per plant in eggplant improvement.