Interrelationship between yield attributing and quality traits and theireffect on bulb yield in Onion (Allium cepaL.)

Abstract

The development of kharif onion cultivar is a better option to meet the onion demands and stabilize the market price. The present investigation was conducted to evaluate eighteen onion (Allium cepa L.) genotypes for elucidating the genetic variability as well as the interrelationship between yield attributing and quality traits on onion bulb yield. The genotypes were evaluated consecutively over two years following Randomized block design maintaining three replications. The result revealed the presence of substantial variability for all the studied traits among the onion genotypes. Characters like plant height, double bulb percent, total bulb yield, marketable bulb yield, dry matter, and pyruvic acid content in bulb exhibited high heritability coupled with high genetic advance as a percentage over mean, indicating the influence of additive genetic variance. The present data set also revealed the existence of non-additive variation for traits like days to maturity, polar diameter, and equatorial diameter of the bulb, highlighting the possibility of heterosis breeding for improvement of these traits. Correlation studies indicated that the genotypic correlation coefficients were higher than the corresponding phenotypic correlation coefficients for all the characters reflecting the predominant role of heritable factors. Onion genotypes with better leaf diameter, polar diameter, equatorial diameter and marketable bulb yield with late duration would be beneficial for getting better yield potential. The marketable bulb yield exerted the highest direct effect on total yield. Bulb weight, along with the polar and equatorial diameter of the bulb, were identified as key factors that significantly impact onion bulb yield. The negative correlation of bulb yield with quality traits signified that breeders have to compensate for quality traits during yield improvement. The findings of the present investigation would be valuable for future onion improvement programs.