Assessment of correlation and path analysis for morphophysiological characters in Indian mustard genotypes under heat stress condition

Abstract

An experiment was conducted with 18 genotypes of Indian mustard (Brassica juncea L. Czern& Coss) in a Complete Randomized Block Design (CRBD) with 3 replications at the ICAR-Directorate of Rapeseed-Mustard Research during the rabi season of 2020-21. The purpose of the study was to assessment the correlation and path analysis for 21 distinct characteristics. The results show that certain traits are positively correlated with seed yield, including the number of secondary branches per plant, main shoot length (cm), siliqua on the main shoot, siliqua per plantand seeds per siliqua. In contrast, there are significant negative correlations with membrane stability index (%), excised leaf water loss (%) and water retention capacity of leaves (%). Generally, genotypic correlation coefficients are slightly higher than phenotypic correlation coefficients. Path coefficient analysis revealed that traits such as siliqua on main shoot length, relative water content (%), plant height (cm), chlorophyll b (mg/g FW), excised leaf water loss (%) and total chlorophyll (mg/g FW) have direct positive effects on seed yield per plant (g). Conversely, primary branches per plant, main shoot length (cm), water retention capacity of leaves (%) and days to maturity have direct negative effects on seed yield. These findings suggest that both morphological and physiological characteristics significantly impact the yield potential of a genotype, making these traits useful for genotype selection.