Effect of nitrogen management on growth and physiological parameters of sweet corn (Zea mays saccharata) under organic farming conditions

Abstract

The increasing demand for sustainably grown produce has amplified the relevance of organic farming, particularly for high-value crops like sweet corn (Zea mays saccharata). This study evaluated the impact of different organic nitrogen management strategies on growth and physiological parameters of sweet corn under organic farming conditions in the sub-humid southern plains of Rajasthan. A field experiment was conducted during the Kharif season of 2022 at MPUAT, Udaipur, using a randomized block design with eight treatments combining solid (FYM, vermicompost, neem cake) and liquid (jeevamrit, ghanjeevamrit, vermiwash) organic inputs. Key parameters observed included plant height, dry matter accumulation, leaf area index (LAI), chlorophyll content, crop growth rate (CGR), relative growth rate (RGR), and phenological events (tasseling and silking). Results revealed that the treatment combining 50% recommended dose of nitrogen (RDN) through FYM with 25% RDN applied through vermicompost at 30 and 45 days after sowing (T6) consistently recorded superior growth attributes. T6 exhibited the highest plant height (195.60 cm), dry matter (191.89 g plant⁻¹), CGR (12.79 g m⁻² day⁻¹), LAI (2.08), and chlorophyll content (2.25 mg g⁻¹), outperforming other treatments. No significant differences were observed in tasseling and silking dates, indicating that phenological traits remained stable across nitrogen treatments. The study concludes that phased application of integrated organic nitrogen sources, especially combining FYM and vermicompost, can effectively enhance sweet corn productivity and support sustainable organic agriculture in the region.