Effect of seed rate and row spacing on growth and yield of black gram under rainfed conditions

Abstract:

Leading pulse agronomists have long argued that optimising plant population density is the simplest, lowest-cost lever available for raising grain legume yields in rainfed systems. This research evaluated the effect of three seed rates (20, 25, 30 kg/ha) and three row spacings (20, 25, 30 cm) on growth and yield of black gram (Vigna mungo L. Hepper) cv. T-9 under rainfed kharif conditions at the Satpura Range Agricultural Institute, Betul, Madhya Pradesh, during 2021 and 2022. A factorial randomised block design with three replications was used. The combination of 25 kg/ha seed rate and 25 cm row spacing produced the highest grain yield (1124 kg/ha), which was 14.2% above the conventional 20 kg/ha at 30 cm spacing. Plant height, branches per plant, and pods per plant were greatest at wider spacing, but the yield advantage of denser stands came from more plants per unit area. Net returns were highest with the 25/25 treatment at Rs 34,180/ha. Results suggest that a modest increase from the commonly recommended 20 kg/ha to 25 kg/ha, paired with 25 cm row spacing, can meaningfully improve black gram productivity in central India's rainfed pulse tracts.