Genetic Divergence Analysis in Indian Mustard [Brassica juncea (L.) Czern & Coss] Genotypes

Abstract

A study was carried out with 40 genotypes of Indian mustard [Brassica juncea (L.) Czern and Coss.] to examine the degree of genetic divergence within these genotypes. These genotypes were tested in randomized block design with three replications during rabi season of 2022–23 and 2023–24 under early and late planting. The degree of genetic divergence was studied in forty genotypes of Indian mustard [Brassica juncea (L.) Czern and Coss.] by using the pooled data of 4 environments (early and late sown). The analysis of variance (ANOVA) showed significant variation for all the thirteen characters (Table 1). Further, the estimates of genotypic and phenotypic variance were maximum for number of siliqua followed by biological yield, plant height, days to 50% flowering and days to maturity indicated sufficient genetic variability available in the material. The analysis was carried out in 40 genotypes of Indian mustard [Brassica juncea (L.) Czern & Coss.] using Mahalanobis D2 statistics followed by Rao (1952) for thirteen characters. Genotypes were found to be into seven clusters. The cluster VI had the largest number of genotypes (nine) followed by cluster IV (eight), V(eight), III (six), I (five) and II (four). Results shown that number of primary branches per plant, length of siliqua, plant height, seeds per siliqua and number of secondary branches per plant were the major contributors towards genetic diversity. The maximum intra cluster divergence was in cluster III followed by I, II, VI, V and IV, while maximum inter cluster divergence observed between cluster I and VI followed by cluster II and III, cluster III and VI and cluster I and V which indicates that efficient breeding programme can be formulated to improve yield by hybridization between genotypes of these clusters.