Estimation of Combining Ability for the Development of Hybrid Genotypes in Helianthus annuus L

Abstract

Plant materials were developed by L×T crossing fashion of nine lines and four testers and their thirty six hybrids were sown in field during 2011 in RCBD design with three replications. Genetic variability, general and specific combining abilities among genotypes was assessed under the research area of department of plant breeding and genetics, university of agriculture, faisalabad, Pakistan. The Line G-93, and G-79 expressed highly significant GCA effects for days to flowering, days to maturity, internodal length, head diameter, %age of filled achenes, 100 achene weight, achene yield per plant and oil contents but they showed best general combiner. Among testers A-85 expressed highly significant GCA effects for days to flowering, days to maturity, 100 achene weight, achene yield per plant and oil contents whereas A-5 exibited best general combiner for days to flowering, days to maturity, internodal length, achene yield per plant and oil contents. The cross G-65×A-85 revealed highest SCA effect for days to 50% flowering and days to maturity, head diameter, 100 achene weight, achene yield per plant and oil contents. The results of analysis of variance were determine among entries for all the traits at significant level (p ? 0.01-0.05).

Key words: GCA, SCA, line × tester, oil contents and yield.