Role of biodegradable substrates in improving productivity and quality of Sweet Pepper (Capsicum annuum L.)

Sweet pepper ( Capsicum annuum L.) is a nutritionally and economically important crop; however, identifying sustainable and efficient substrate options for its cultivation remains a major challenge in horticultural production. This study evaluated biodegradable substrates silt, perlite, cocopeat, farmyard manure (FYM), compost, and vermicompost, applied individually or in mixtures under controlled pot culture, with farm soil as the control. Nine treatments (T₀–T₈) were arranged in a completely randomized design. Morphological traits (leaf area, stem length, root biomass), yield attributes (fruit number, fruit weight, total yield), and physiological indicators (chlorophyll content, relative water content, electrolyte leakage, proline accumulation, and antioxidant enzyme activities) were assessed. The silt + FYM (1:1) treatment significantly increased leaf area (189.5 cm²), root fresh weight (29.99 g), average fruit weight (109 g), and total yield (1300.75 g), representing increases of 29%, 47%, 28%, and 156% over the control, respectively. Silt + compost (1:1) achieved the highest relative water content (53%), while mixed substrates enhanced chlorophyll and proline accumulation, indicating improved physiological performance and stress tolerance. Overall, integrating organic substrates such as FYM or compost with silt enhanced substrate functionality, plant resilience, and sweet pepper productivity, offering practical insights for sustainable horticultural systems.