Genotypic variation in nitrogen use efficiency and yield stability of 28 indica hybrid rice cultivars under tropical nitrogen gradients

Introduction: Excessive nitrogen (N) application is a prevalent issue in tropical rice production, often leading to environmental degradation without guaranteeing yield gains. Exploiting genotypic potential for low-N tolerance is essential for sustainable intensification. Methods: ¹) in the tropical climate of Hainan, China. Results: ¹) without yield compromise. Discusssion: These "N-efficient and stable-yielding" varieties demonstrated superior N agronomic efficiency, suggesting that optimizing variety selection can reduce rice productivity's dependence on high N inputs. These results provide scientific support for N reduction and efficiency-enhancement strategies in tropical agroecosystems.