Vol. 9, Special Issue 10, Part X (2025)

A field experiment was conducted during rabi season of 2024 at farmer’s field of Nailady village, Brahmavar, Udupi, Karnataka, to evaluate the impact of different liming materials and magnesium sulphate on the growth, yield and quality parameters of Mangaluru melon (Cucumis melo var. acidulous) under acidic soil condition of coastal Karnataka. The study involved ten treatments with three replications viz., Package of practice (T₁), lime and dolomite applications at 50 and 100% equivalent to exchangeable acidity and their combinations with magnesium sulphate at levels of 10 and 20 kg ha^-1. Among all treatments, T₄ (POP + lime at 50% exchangeable acidity + 20 kg ha^-1 MgSO₄) recorded the highest performance across the growth, yield and quality parameters: Vine length (201.30 cm), Number of leaves (44.33), Number of branches (6), fruit length (21.73 cm), fruit diameter (14.27 cm), Individual fruit weight (1.25 kg), yield per hectare (21.53 ton ha^-1), shelf life (111.10 days) and ascorbic acid content (27.43 mg 100 g^-1). Treatment T₃ (POP + lime at 50% exchangeable acidity + 10 kg ha^-1 MgSO₄) also showed significantly improved results, indicating the synergistic role of magnesium sulphate with liming materials in acidic soils of coastal Karnataka. In contrast, T₁ (POP) and T₁₀ (farmer’s practice) exhibited the lowest values across parameters, reaffirming the negative impact of untreated soil acidity on crop performance. Treatments involving dolomite (T₈ and T₉) showed modest improvements over control, but were less effective than pure lime with magnesium sulphate application. Notably, applying lime equivalent to 50 and 100% exchangeable acidity without magnesium sulphate (T₅) underperformed compared to lime treatments with MgSO₄ application, suggesting over liming may suppress nutrient uptake. Overall, the study suggests that amending soil with lime at 50% exchangeable acidity combined with magnesium sulphate of 20 kg ha^-1 significantly enhances the growth, yield and nutritional quality of Mangaluru melon, making it a viable soil management practice for acidity prone coastal regions.