000			02677nam a2200217 4500
003			OSt
005			20250214113330.0
008			250214b |||||||| |||| 00| 0 eng d
040			_cUAS Dharwad
041			_aEnglish
082			_a581.56 _bSWA
100			_aSwamy Shivani M. K.
245			_aHeterosis and Combining Ability Studies in Sunflower (Helianthus Annuus L.)
250			_aM.Sc. (Agri)
260			_aDharwad _bUniversity of Agricultural Sciences _c2024
300			_a143 _c32 Cms
520			_aABSTRACT Sunflower (Helianthus annuus L.) a cross-pollinated crop, occupies a strategic position in food security as an important edible oilseed crop globally, due to its adaptability, short growth cycle (85–100 days), high yield potential, and photoperiodic insensitivity. The present study aims to introduce new inbreds resulting from mutation breeding, as well as the hybridization of B and R lines with TX-16R (Texas Red 16), to enhance the yield quality of hybrids by providing resistance to major biotic stresses. A line × tester mating design, with four CMS lines and twelve testers, was employed, resulting in 48 hybrids during Rabi 2023. The parents, hybrids, along with three checks, were assessed for general combining ability (GCA), specific combining ability (SCA) and heterosis using a Randomized Complete Block Design (RCBD) with two replications during Summer 2024. The analysis of variance revealed significant differences for most traits, indicating the diversity and potential of the parent lines used. The study found that SCA variance was higher than GCA variance for all traits, suggesting that non-additive gene action was predominant. CMS-17A and CMS-103A emerged as the best general combiners among the female parents, while DSR-35 was the top general combiner among the testers for seed yield and disease resistance, followed by DSR- 125, DSR-107, and PGS-3-1. SCA is a good predictor of per se performance. The hybrids CMS-17A × PGS-2-1, CMS-103A × DSR-37, and CMS-335A × PGS-3-1 were identified as good specific combiners for multiple important traits, including seed yield per plant and oil content. Heterosis analysis showed significant positive effects for seed yield, with CMS-234A × DSR-35 and CMS-17A × PGS-2-1 demonstrating high heterosis over the mid-parent and standard checks. Additionally, several hybrids exhibited resistance to Alternaria leaf blight, with CMS-17A × DSR-107, CMS-17A × PGS-2-1, and CMS-234A × DSR-35 identified as resistant and high-yielding.
650			_aGenetics and Plant Breeding
700			_aVijayakumar A. G.
942			_cTH _eM.Sc. (Agri) _h581.56 _kSWA _n0 _6581_560000000000000
999			_c70854 _d70854