Biomass Production, Nutrient Uptake and Soil Availability across Varying Manure Levels, Phosphorus Sources, and Nitrogen Application Timing in Brinjal Crop (Solanum melongena L.) Grown in Loamy Sand Alluvial Soil

An experiment was carried out at Punjab Agricultural University, Regional Research Station, Bathinda during kharif 2020-2021 in a loamy sand alluvial soil with brinjal hybrid PBHR-42 to find out the effect of manure levels, P sources, nitrogen application timing on biomass yield, nutrients uptake and soil availability after crop harvest. Highest plant and fruit fresh biomass (6.7 t ha^-1 and 65.4 t ha^-1) and dry biomass (8.71 q ha^-1 and 51.03 q ha^-1) was recorded with treatment T₇:FYM (12.5 t ha^-1) + N (156 kg ha^-1) + P₂O₅ (62.5 kg ha^-1) (DAP) and application of N at 30 & 60 DAT. The treatment T₇ showed the highest plants and fruits N (1.5% and 2.61%) and K (1.06% and 1.23%) content, total N and K uptake (147.1 kg ha^-1 and 72.11 kg ha1). However, maximum P content (0.37% and 0.51%) in plant and fruit, total P uptake (25.1 kg ha^-1) was recorded with treatment T₃: FYM (25 t ha^-1) + N (125 kg ha^-1) + P₂O₅ (62.5 kg ha^-1) (DAP) and application of N at 30 & 60 DAT. Similarly, highest plant and fruit Fe (23.2 and 35.4 mg kg^-1), Cu (13.8 and 19.0 mg kg^-1), Zn (36.9 and 55.4 mg kg^-1), Mn (65.9 and 89.9 mg kg^-1) content and total uptake of Fe (170.6 g ha^-1), Cu (93.4 g ha^-1), Zn (267.4 g ha^-1) and Mn (439.6 g ha^-1) was observed with T₃. Highest soil N (228.8 kg ha^-1) and soil K (352.6 kg ha^-1) was recorded with T₇, while soil P (65.9 kg ha^-1) and micronutrients viz. Fe (6.3 mg kg^-1), Cu (0.62 mg kg^-1), Zn (1.1 mg kg^-1) and Mn (4.9 mg kg^-1) were recoded with T₄: FYM (25 t ha^-1) + N (125 kg ha^-1) + P₂O₅ (62.5 kg ha^-1) (DAP) and application of N at 30 & 75 DAT after crop harvest.