Genetic variability, correlation and path analysis of yield and yield components in onion

Evaluation of 30 varieties and local land races of onion revealed that PCV was higher than GCV for different traits. High heritability with moderate to high GCV and genetic gain were recorded for bulb neck thickness, bulb weight and bulb yield which could be improved by simple selection. Moderate to high heritability with low GCV and genetic gain were observed for plant height, days to maturity, number of leaves per plant, equatorial bulb diameter and dry matter content which warrant heterosis breeding for their amelioration. The genetic correlation were higher than corresponding phenotypic ones for most characters implying inherent relationship among them. Bulb yield expressed positive and significant phenotypic and genetic association with plant height, number of leaves per plant, bulb neck thickness, bulb weight, equatorial and polar bulb diameter. Path analysis showed that plant height, number of leaves per plant, bulb neck thickness, bulb weight, equatorial and polar bulb diameter had high positive direct effect through each other on yield. Other characters also exerted positive indirect effect via these traits on yield suggesting to give emphasis on such traits simultaneously or in combination with diameter of bulb while imposing selection for amenability in bulb yield of onion crop.