Genetic variability, character association and path analysis for yield and yield attributing traits in lettuce (Lactuca sativa)

Abstract

An experiment was conducted to assess the genetic variability and relationship among the important horticultural traits in lettuce (Lactuca sativa L.). A wide range of variability among selected genotypes was observed for specific traits. A little or very less difference was observed between the genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) for all traits indicated the least environmental influence, which suggests that selection can be done based on the phenotypic performance. Higher estimates of heritability coupled with higher genetic advance for plant weight, yield, average leaf weight, leaf width indicated the presence of additive gene action, through which selection can be done. Yield (q/ha) showed highly significant positive correlation with plant weight, stem diameter, leaf size at genotypic and phenotypic level. Significant positive direct effect on yield by average plant weight, leaf length, average leaf weight and stem diameter and their significant positive correlation with yield as well as high heritability coupled with high genetic advance suggested them as the most important components contributing to yield. Thus, more weight should be given to these traits in yield improvement programme of lettuce for future line of work.

Studies on correlation and path coefficient analysis to explore the inter-relationships among grain yield and related traits in Indian mustard (Brassica juncea L. Czern and Coss.) particularly under timely and late sown conditions

“…All the traits except plant height and primary branching exerted high extent of positive indirect effects on seed yield per plant via harvest index in both E1 and E2 conditions i.e., biological yield per plant (0.4150 and 0.2284), number seeds per siliqua (0.3789 and 0.3324), secondary branching (0.3435 and 0.3093), no. of silique on main raceme (0.3324 and 0.3346), length of main raceme (0.3046 and 0.2714), days to maturity (0.2140 and 0.1620), 1000-seeds weight (0.2125 and 0.1887), and days to 50% flowering (0.1965 and 0.2292), Similar finding were reported by Yadava et al (2012) [21] , Yohannes and Belete (2013) [22] , Singh et al (2013) [14] , Lodhi et al (2014) [5] , Shekhawat et al (2014) [13] , Tahira et al (2015) [18] , Dipti et al (2016) [3] , Singh et al (2017) [16] , Rauf and Rahim (2018) [9] , Nur-E-Nabi et al (2019) [7] and Tripathi et al (2020) [19] . At phenotypic level, the highest positive direct effect on seed yield/plant was exerted by harvest index (0.8102 and 0.8463 respectively) followed by biological yield per plant (0.4382 and 0.4529) respectively in E1 and E2 conditions.…”