Deciphering Genetic Variability and Trait Pathways Governing Yield in Pearl Millet

Abstract

Pearl millet (Pennisetum glaucum L.) is a climate-resilient nutri-cereal that plays a critical role in food and nutritional security in arid and semi-arid regions; however, genetic improvement for grain yield remains challenging. The present investigation was undertaken to quantify genetic variability and to elucidate causal trait pathways influencing yield among diverse germplasm, with the scientific objective of identifying reliable indirect selection criteria for breeding high-performing cultivars. The experiment evaluated 35 pearl millet germplasm lines in a randomized block design with three replications under field conditions. Highly significant variation was observed for all quantitative characters, confirming substantial exploitable genetic diversity. Moderate to high heritability coupled with appreciable genetic advance was detected for tiller number and stem diameter, while correlation analysis revealed strong positive associations of yield with plant height, leaf dimensions, and biomass parameters. Path analysis indicated that stem fresh weight, stem diameter, and leaf number exerted the strongest direct positive effects on grain yield, whereas certain vegetative traits influenced yield predominantly through indirect pathways. These findings demonstrate that effective yield enhancement in pearl millet can be achieved through indirect selection emphasizing biomass-related and structurally stable traits rather than yield alone.