Combining ability analysis for yield and its components in Indian mustard [Brassica juncea (L.) Czern & Coss] using half diallel

Abstract

Half diallel analysis excluding reciprocals, comprised of eight parents with two checks was carried out to identify high heterotic crosses and their relationship in terms of general and specific combining ability (GCA and SCA) in Indian mustard in year 2022-23. Analysis of variance for GCA and SCA signify differences for all the traits. Ratio of GCA and SCA variances was below unity for all the characters except days to flowering, plant height and harvest index, which suggested superior role of non-additive genetic variance in the inheritance of these traits. GCA analysis identified specific parental lines with consistently positive effects for various traits. These lines, such as P3, P4, P5, and P7 for early flowering and maturity or P2, P4, and P7 for increased seed weight, can be employed strategically in breeding programs to enhance specific traits in offspring. SCA analysis revealed promising cross combinations exhibiting significant positive effects for several traits. These crosses, like P1 X P7 for earlier flowering, P1 X P4 for increased seed weight, and P4 X P5 for enhanced biological yield, represent valuable breeding material for exploiting heterosis and developing superior mustard varieties.