Genetic Variability, Trait Association and Path Analysis for Yield and Yield-Contributing Traits in Linseed (Linum usitatissimum L.)

Abstract

Linseed (Linum usitatissimum L.) is an important oilseed crop in which improvement of seed yield depends on the availability of genetic variability and the identification of useful yield-associated traits. The present investigation was undertaken to assess genetic variability, heritability, genetic advance, correlation and path relationships for ten quantitative traits in 40 linseed genotypes. The experiment was conducted during rabi 2024–2025 at the College of Agriculture, Latur, Maharashtra, India, in a randomised block design with two replications.  The traits evaluated included days to 50% flowering, days to maturity, plant height, number of branches per plant, number of capsules per plant, number of seeds per capsule, 1000-seed weight, oil content, harvest index, and seed yield per plant. Analysis of variance revealed significant differences among the genotypes for all the assessed traits.The recalculated estimates showed that GCV ranged from 4.61% for days to maturity to 22.15% for number of branches per plant, while PCV ranged from 5.14% for harvest index to 22.53% for number of branches per plant. Broad-sense heritability ranged from 63.06% for days to maturity to 98.24% for harvest index. Genetic advance as a percentage of the mean was highest for number of branches per plant (44.86%), followed by oil content (35.74%), 1000-seed weight (28.49%), number of capsules per plant (26.80%), number of seeds per capsule (26.16%) and seed yield per plant (25.96%). At the genotypic level, seed yield showed positive associations with number of branches per plant (0.7118), number of capsules per plant (0.7044), number of seeds per capsule (0.7265), plant height (0.0073) and 1000-seed weight (0.0141). The reported path analysis indicated positive direct effects of number of seeds per capsule (0.8083) and number of capsules per plant (0.3397) at the genotypic level, while number of branches per plant showed a high positive direct effect at the phenotypic level (1.6152). Thus, number of branches per plant, number of capsules per plant and number of seeds per capsule may be considered important selection criteria for improving seed yield under the present experimental conditions. The study was conducted at one location in one season; therefore, further multi-location and multi-season evaluation is necessary.