Integrated nutrient management in red okra: Impact on yield, quality parameters, soil properties and profitability

Abstract:

A field experiment was conducted during the summer season of 2023 in the experimental farm, Dr. Balasaheb Sawant Konkan Krishi Vidyapeeth, College of Horticulture, Dapoli, Maharashtra to study the response of integrated nutrient management (INM) practices on the soil properties, fruit yield, quality parameters, and economics of red okra variety Laal Bhendi No. 533. The crop was sown in a randomized block design with 9 treatments consisting of 100% or 75% of recommended dose of fertilizer (RDF) 100:50:50 or 75:37.5:37.5 kg NPK/ha + 10 t vermicompost/ha + biofertilizers (Azospirillum, Azotobacter, VAM or PSB @ 5 kg/ha). Treatments were spaced at 45 cm × 30 cm apart, and treatment T₂ registered the highest fruit yield (17.72 t/ha), anthocyanin (3.68 mg/100g), chlorophyll (0.476 mg/100g), crude fibre (8.93%), ascorbic acid (15.86 mg/100g), net returns (₹1,64,413/ha), and B:C (1.59) over the control T₁ (12.33 t/ha; ₹81,417/ha; B:C 1.35). Treatments T₆-T₉ (75% RDF + vermicompost + biofertilizers) recorded 14.35-15.76 t/ha fruit yield and 3.55-3.65 mg/100g anthocyanin with lower costs (₹2,45,040-2,58,252/ha), B:C (1.46-1.52), and comparable shelf life (2.04-2.06 days). After-harvest soil analysis indicated that T₂ (100% RDF + vermicompost (10 t/ha) + Azospirillum (5 kg/ha)] recorded the highest organic carbon (1.80%) and available N (219.66 kg/ha), P (17.03 kg/ha), and K (230.63 kg/ha) over the initial status of the soil (pH 5.02, EC 0.212 dS/m, OC 1.24%, N 250.53 kg/ha, P 18.83 kg/ha, and K 260.86 kg/ha), while the pH (5.04-5.07) and EC (0.199-0.209 dS/m) remained non-significant.