Full root-zone nitrogen fertilizer application during rice transplanting promoted root development to increase rice yield and improve nitrogen use efficiency in South China

The experiment results demonstrated that at the tillering stage, the RF method significantly enhanced rice root characteristics over the BF method, with increases of 24.41% in average root length, 34.93% in diameter, and 25.22% in total root surface area. The tiller number and the antioxidant enzymes activity under the RF method were significantly higher than the DF and BF methods during the rice growth period. The rice yield under RF method increased 13.87% to 33.41% compared with BF and DF methods. This increase was associated with superior performance in effective panicle number and seed setting rate at maturity. The RF method also significantly enhanced nitrogen use efficiency (NUE) compared to other methods, by reducing nitrogen loss and improving plant nitrogen uptake. Additionally, the RF method increased net income by 31.77% to 45.33% over the DF and BF methods by raising the total rice value.