Heterosis Analysis for Grain Yield and Its Attributing Traits in Pearl Millet [Pennisetum glaucum (L.) R. Br.)] Using Cytoplasmic Male Sterile Based Hybrids

Abstract

A line × tester mating design involving five CMS lines and nine restorer lines of pearl millet [Pennisetum glaucum (L.) R. Br.] was used to generate 45 F₁ hybrids, which were evaluated along with their parents and a standard check hybrid (GHB 1129) for nine agronomic and yield-related traits. The hybrids showed substantial variation for most traits, and the analysis of variance indicated ample genetic variability and significant differences among both female and male parents. Marked heterotic responses were observed particularly for grain yield per plant, number of effective tillers per plant, earhead length, and harvest index, whereas days to 50% flowering, earhead girth, and test weight expressed comparatively lower to moderate levels of heterosis. Among the crosses, ICMA 15666 × HBL-11 R consistently recorded the highest relative heterosis and maximum heterobeltiosis for grain yield per plant, followed by ICMA 15666 × ICMR 11666, indicating the strong yield-enhancing potential of ICMA 15666-based hybrids. Based on per se performance and standard heterosis, four hybrids—ICMA 15666 × HBL-11 R, 7A × ICMR 0911, ICMA 14222 × ICMR 17333, and ICMA 21999 × ICMR 08222—were identified as superior to GHB 1129 for grain yield per plant, with several of them also expressing desirable heterosis for earhead length, earhead girth, and test weight. The predominance of highly heterotic combinations, particularly those involving complementary CMS and restorer parents, highlights the effectiveness of the line × tester approach for identifying elite hybrid combinations and provides promising genetic material for developing high-yielding, heterosis-based pearl millet hybrids suited to dryland production environments.