Genetic Parameters and Heritability of Sunflower Genotypes as Influenced by Different Nitrogen Rates

Abstract

This study was carried out to estimate the genetic parameters, heritability in broad sense, Phenotypic coefficient (PCV), Genotypic coefficient (GCV) and phenotypic and genotypic correlation among characteristics of sunflower genotypes. Eight sunflower genotypes were evaluated in the randomized complete block design (RBCD) with three replications under three nitrogen rates (50, 100 and 200) Nkha-1 at spring and fall season. The results indicated that the sunflower genotypes were significantly for all characteristics. The phenotypic coefficient (PCV) was largest than the genotypic coefficient (GCV). The seed yield showed the highest PCV under 200 Nkha-1 (15.73) and the highest GCV (12.48) under 50 Nkha-1. Higher value of heritability in the broad sense was obtained (92.66, 94.13) % for seed weight and seed yield under (200) Nkha-1. while the lowest value of heritability was scored (44.56)% for seed yield in the fall season under 200 Nkha-1. However, characteristics having high stability, like disc diameter and seed weight under all nitrogen fertilizer rates, therefore can be used a selection criteria to improve some sunflower genotypes under nitrogen fertilizers.