Assessment of the effects of conventional urea and Nano urea on nutrient status of the soil and yield of tomato (Lycopersicum esculentum) crop

Fertilizers play a vital role in enhancing crop productivity, but their indiscriminate use can lead to soil nutrient imbalances, environmental pollution, and decreased sustainability. In recent years, Nano fertilizers have emerged as a promising solution for efficient farming and reduced environmental impact. In this context, the present study titled “Assessment of the effects of conventional urea and nano urea on nutrient status of the soil and yield of tomato (Lycopersicum esculentum) crop” was conducted at the University of Horticultural Sciences, Bagalkot (2022-2023) using a randomized complete block design with 12 treatments and three replications, for testing different nitrogen levels (100%, 75% and 50% recommended dose of nitrogen (RDN)) via urea and nano urea (2 ml L-1). The findings indicated a reduction in soil pH across all treatments compared to the initial pH (7.62). Notably, the soil pH varied between 7.51 to 7.24 among the treatments. The conjoint application of urea and nano urea significantly impacted primary and secondary nutrient levels in the soil. Application of 100% RDN (50% as basal dose and another 50% in two equal splits of urea at 30 and 45 Days after transplanting recorded the highest levels of N (287.43 kg/ha), K (326.77 kg/ha), Ca (14.30 c mol (p+) kg-1 soil), and Mg (3.73 c mol (p+) kg-1 soil). Whereas, the application of 100% RDN: 50% as basal dose + foliar application of nano urea (2 ml L-1) at 30 and 45 days after transplanting yielded the highest (59.41 kg/ha) P content, and application of 50% RDN: 50% as basal dose + foliar application of nano urea (2 ml L-1) at 30 and 45 days after transplanting had the highest (20.81 ppm) S content, but there is no significant differences were observed in micronutrient content among the treatments. However, the yield of tomato recorded maximum (56.97 tons ha-1) with the application of 100% RDN: 50% as basal dose + foliar application of nano urea (2 ml L-1) at 30 and 45 days after transplanting. These findings can guide optimized fertilizer strategies for tomato cultivation.