Genetic advance and regression analysis in sunflower

Abstract

The knowledge about the magnitude and nature of variability that is present in a breeding population is an important prerequisite for designing efficient breeding programme in order to improve the yield potential of genotypes. The objective of this research was to evaluate heritability and genetic advance of important quantitative traits in new crosses of sunflower as well as to evaluate ratio of dominant and recessive genes in parental genotypes. The plant material selected for this research consisted of 6 sunflower genotypes, which according to literary data possess important characteristics for the production of sunflower. According to presented results there is significant variability of evaluated quantitative traits. Phenotypic variance was higher than genotypic demonstrating strong environment effect in expression of traits. The broad sense heritability was found very high for plant height (83.25%), high for 1000 seed weight (69.33%), moderate for seed yield/plant (46.53%) and head diameter (56.89%), while low for oil content (29.35%). Genetic advance expressed as a percentage of the mean ranged between 2.23% and 19.96%. Placement of array points displayed that the highest frequency of dominant genes for seed yield/plant, 1000 seed weight and head diameter was found in parental genotype Rodnik. Position of expected line of regression pointed over dominance in inheritance for seed yield/plant, oil content and head diameter, while for 1000 seed weight and plant height additive gene action played role in inheritance suggesting that selection in early generations for these traits will be effective. By testing the coefficients of regression interallelic interaction was not determined.