Impact of different rates of N2 fertilizer amendment and foliar spraying with compost tea on the Biological activity and the productivity of rice plants

Currently, compost tea combined with N chemical fertilizer raises the soil's soluble salts and microbial biomass, which in turn increases rice plant yield. A field experiment was conducted in two consecutive seasons in 2023 and 2024 at the Rice Research and Training Center experimental farm in Sakha, Kafrelsheikh, Egypt, to evaluate the effects of different chemical N dosages (55, 110, and 165 kg N ha-1) in combination with foliar spray and compost tea (140 L ha-1) on soil microbial activity, nutrient content, and rice plant yield (Giza 183). Three replicates of a randomized Complete Block Design were employed. According to the findings, the total number of aerobic, N2-fixing, nitrogen-fixing cyanobacteria, and nitrifier bacteria was significantly (P ≤ 0.05) increased when chemical N fertilizer was mixed with compost tea. Higher fertilizer nitrogen rates, however, resulted in a substantial drop in the number of sulphate-reducing bacteria, suggesting that transplanting may have an effect on the soil quality in rice plants at 60 DAS. Additionally, the treatment of 165 kg N ha-1 + with compost tea resulted in a considerable increase in the highest values of dry matter, grain weight, filled grain per panicle, filled grain percentage, and yield. The microbial communities in compost tea may be the cause of this rise since they promote plant development and nutrient uptake, which increases output. Additionally, as compared to the control treatment, the maximum values of N and protein percentage were obtained with an application of 165 kg N ha-1 with spray compost tea.