Estimation of standard heterosis and heterobeltiosis for yield and fiber quality traits in Karunganni cotton (Gossypium arboreum L)

The primary objective of any plant breeding program is to develop high-yielding cultivars with desirable traits. In the context of cotton production, overcoming the yield plateau can be accomplished by identifying and utilizing hybrids that exhibit significant economic heterosis. Therefore, this study was undertaken to evaluate the heterotic potential of 30 hybrids generated from six parental plants. The experimental setup consisted of a full set of 36 entries, including the six parents, the 30 resulting F1 hybrids, and two standard checks (K12 and RG-8). All entries were sown during the Kharif season of 2022 at the Department of Cotton, TNAU. The analysis of variance revealed highly significant mean squares attributed to genotypes for each trait examined. Notably, the hybrids RG763 × K12, K12 × PDB29, and K12 × RG763 exhibited statistically significant and desirable heterosis for multiple yield-related traits, including the number of sympodia, boll weight, seed cotton yield per plant, seed index, and lint index. Moreover, the cross PDB29 × PA838 demonstrated positive heterosis for fiber quality parameters such as upper half mean length, fiber strength, and elongation percentage. Hence, these particular crosses hold the potential for exploitation in heterosis breeding programs aimed at enhancing cotton productivity.