Heterosis and combining ability analysis using landrace-based hybrids for yield and yield components in rabi sorghum

Abstract

Sorghum, called the “King of Millets,” is a staple cereal in the semi-arid tropics of Africa and Asia, and in India it is grown in both kharif and rabi seasons. Hybrid breeding mainly relies on heterosis and commonly uses the A1 (milo) cytoplasm source, but rabi hybrids remain less popular due to poor adaptation. Landraces, with their genetic diversity and natural stress tolerance, offer strong potential for developing climate-resilient hybrids. Such landrace-based hybrids help maintain productivity under limited water conditions and support food security in climate-vulnerable regions, making them important for sustainable sorghum cultivation. With this idea, a trial was undertaken at the Regional Agricultural Research Station, Vijayapura, to evaluate 18 hybrids (2 lines and 9 testers including landraces) and five checks using Line × Tester design during rabi 2022 for ten yield related traits. Notable variations were identified among hybrids, with varying Line × Tester interactions. The two testers showed strong additive genetic effects for test weight, while the cross 104A×RLT-9 exhibited noteworthy non-additive genetic effects for panicle weight, grain yield, and other traits, indicating its potential in heterosis breeding programs. Likewise, the principal component analysis uncovered distinct trait variability, with grain yield and related traits (viz: grain yield, panicle weight, and harvest index) driving major variation. GCA and SCA biplots identified key parents and hybrids contributing to yield improvement. This information would be valuable for selecting parent plants to improve specific morphological traits towards development of increased potential genotypes in sorghum.