HERITABILITY AND CORRELATION STUDIES FOR PHENOLOGICAL, SEED YIELD AND OIL TRAITS IN SUNFLOWER (HELIANTHUS ANNUUS L.)

Abstract

The present studies were carried out during 2009 at Agriculture Research Institute, Tandojam, Pakistan. Six sunflower lines T-4-0319, PAC-0505, HO-I, Hysun-33, Peshawar-93 and CMS-03 and three testers PAC-0306, PAC-64-A and SF-187 were crossed in a line x tester mating design, thus 18 F₁ hybrids were developed for evaluation through genetic analysis. Significant differences were observed among the lines, testers and lines x testers interactions for phenological, seed yield and oil traits in F₁ hybrids. The significance of mean squares of lines and testers determined additive variances while lines x testers interactions estimated the importance of dominant variances, thus the data were worth for estimating heritability for earliness, morphological and yield traits. The major role of dominant genes was very obvious because the degree of dominance (?²D/ ?²A) being greater than unity. The heritability estimates were generally low to moderate which may be due to greater portion of dominant variances and genes against the additive variances and genes.  Results suggested that selection for such traits may be exercised in later generations while giving the opportunity of recombination to occur between desirable genes. Generally, correlations suggested that leaves plant^-1, head diameter and 1000-achene weight have shown strong associations with seed and oil yields, and these traits may be used as reliable selection criteria to improve seed yield and oil content of sunflower.