Rice (Oryza sativa L.) grain yield is reduced by drought stress during reproductive stages. In this work, the effects of foliar selenium (Se) spray on the reduction of drought stress are measured and the most critical stage of rice is identified. Three field experiments were carried out. In experiments I and II, the sensitive stage was determined by imposing drought stress at the panicle initiation and flowering stages by withholding irrigation for 10, 15, 20, and 25 days. In experiment III, drought stress was induced by depriving plants of moisture for 20 or 25 days. Se spray was then applied at rates of 0, 10, and 20 mg L⁻¹ to alleviate the drought, and its effects were evaluated. Overall, it was reported that the panicle initiation stage was more vulnerable to drought stress than the flowering stage, as evidenced by a larger reduction in grain yield. Employing Se as a foliar spray at a rate of 20 mg L⁻¹ under drought stress enhanced the number of filled grains m⁻², the total number of grains m⁻², and grain yield ha⁻¹ by 22.0, 4.3, and 11.0%, respectively, over water spray. This shows a positive interaction or synergistic interaction between drought tolerance and selenium application. These results demonstrate that foliage supplementation of Se at a dosage of 20 mg L⁻¹ alleviate the adverse effects of drought stress at the panicle initiation stage in rice cultivation. Se mitigated the negative effects of drought by improving the membrane stability index, relative water content, and proline content.

Background: Nitrogen plays a crucial role in growth cycling and development, thereby influencing the plant growth and productivity. Understanding the interactions between nitrogen uptake with different irrigation and nitrogen fertilizers could provide a valuable insight for optimizing tomato production. Hence, this study aimed to investigate the effect of nitrogen uptake on tomato production under different nitrogen fertilizer and irrigation regimes. Methods: The field experiment was carried out during 2022-2023 in split plot design with two irrigation main plots treatments and five different nitrogen fertilizer subplot treatments. Irrigation treatments consisted of 0.6 and 0.8 IW/CPE ratio and the nitrogen fertilizer treatments comprised of conventional urea, neem coated urea, ammonium sulfate, nano-urea and vermicompost. Result: A higher nitrogen uptake was observed in the treatment combination of 0.6 and 0.8 IW/CPE ratio with vermicompost and nano-urea fertilizer applied treatments. Additionally, optimal irrigation conditions positively influenced nitrogen uptake and subsequent tomato fruit yield. This finding emphasizes the importance of considering nitrogen uptake when determining nitrogen fertilizer rates and irrigation management strategies for tomato production.