Combining ability analysis in intraspecific (Gossypium hirsutum) cotton hybrids

Neli Valkova, Valentina Dimitrova, Minka Koleva, Spasimira Nedyalkova

Abstract: The aim of this research was to study heterosis, combining ability and gene action for four economic most important traits in 24 F1 hybrids derived from 8 × 3 line × tester crosses. It was found that additive and non-additive gene effects were involved in the inheritance of studied traits. Non-additive variance was predominant over additive one indicating greater importance of non-additive gene action, which means that selection will be more effective in later hybrid generations. From the female parents, as good general combiners were found: Viki and Denitsa for productivity per plant and boll weight; Avangard-264, Natalia, Colorit and Boyana for fiber length; Rumi, Viki and Denitsa for lint percentage, showed positive and high GCA for the relivent traits. The Turkish cultivar Nazili 954 was found as a good male parent for productivity, while the Greek Millennium and the Spanish FR-H-1001 cultivars were determined as the best male parents for lint percentage, and Millennium for boll weight. Some parents were identified as good general combiners for two or three traits.
The Bulgarian Viki and Denitsa varieties were found as good combiners for three traits - productivity, boll weight and lint percentage, the Greek cultivar Millennium for two traits - productivity and boll weight. Some of parents having high GCA had low SCA variances, while others had high SCA variances. All parents having low or high SCA variances could be used in recombinant selection to create new breeding material. The crosses Viki × Nazili 954, Denitsa × Nazili 954 and Boyana × Nazili 954 were the best to improve productivity exhibited high mean performance with positive SCA effects and heterosis of 10.8 - 34.3%. The crosses Nelina × Millennium, Denitsa × Millennium and Avangard-264 × Millennium were the best for lint percentage, while Avangard-264 × Nazili 954, Avangard-264 × FR-H-1001, Natalia × Millennium and Boyana × Millennium were the best for inproving fiber length, showed high mean values with positive SCA effects for the relevant traits. All these crosses are very valuable for breeding programs to create new more productive and better quality cotton varieties.

Keywords: cotton; fiber length; heterosis; line tester analysis; productivity; variance components

Citation: Valkova, N., Dimitrova, V., Koleva, M. & Nedyalkova, S. (2025). Combining ability analysis in intraspecific (Gossypium hirsutum) cotton hybrids. Bulg. J. Agric. Sci., 31(1), 150–159.

Date published: 2025-02-25