Assessment of Genetic Variability and Heritability in Indian Mustard (Brassica juncea L.) Genotypes

Abstract

The present study was undertaken to assess genetic variability and divergence among 42 genotypes sourced from AICRP on Rapeseed and Mustard, ZARS, Morena of Indian mustard (Brassica juncea L.) under field conditions at the Zonal Agricultural Research Station, Morena, Madhya Pradesh, during Rabi 2020–21. The experimental was laid out in a randomized block design with three replications, twelve agronomic traits were evaluated, including phenological, morphological, and yield-related characters. The results revealed that significant genotypic differences were observed for all traits, highlighting substantial variability within the studied genotypes. Notably, genotypic and phenotypic coefficients of variation were moderate to high for key traits such as secondary branches per plant (23.709 and 23.758, respectively), seed yield per plant (15.846 and 15.857, respectively), test weight (15.539 and 15.635, respectively), and siliqua length (11.198 and 15.582, respectively). High heritability (>60%) coupled with high genetic advance was recorded for several traits, including seed yield per plant (99.85%, 32.61%, respectively), indicating the predominance of additive gene action and scope for effective selection. Traits such as plant height, test weight, number of secondary branches, and siliqua length also exhibited promising genetic parameters. These findings suggest that seed yield and its contributing traits could serve as reliable selection indices in mustard breeding programs, providing valuable insights for the development of improved cultivars with higher productivity and desirable agronomic characteristics.