Integrative effect of nitrogen fertilization and biotreatments on rice growth and yield potential under open-field agriculture

Overexploitation of chemical fertilizers is a main threat to the environment, seriously polluting soil and water resources. In this regard, an optimization of N (nitrogen) fertilization in rice in association with biofertilizers is a potential solution. An open-field experiment was conducted during the two consecutive seasons (2019-2020) at the Rice research institute's experimental station in Tashkent, Uzbekistan to reveal the optimized N fertilization of rice in combination with the biotreatments. Rice growth, i.e. plant length, shoot fresh dry weight consistently increased with increasing N fertilization, especially in combination with the biotreatments. However, the most effective dose of N fertilization on yield parameters was observed at 100 kg/ha, when Zamin biofertilizer was used as a seed treatment. The oversupply of N fertilization (150 kg N ha(-1)) remarkably inhibited rice yield and grain quality, resulting in decreased 1000-grain weight, seed output, amylase and protein contents, despite the biotreatments. In conclusion, the optimal N fertilization is more effective in improving growth and yield parameters of rice, while Zamin biotreatment plays an essential role in enhancing plant nutrition balance, N-use efficiency, and yield potential.