Management of plant nutrition using fertilizers is an approach to deal with drought and to increase water productivity in paddies. The aim of this study, therefore, was to investigate the effects of nitrogen and potassium fertilizers and drought stress on water use efficiency (WUE) and physiological traits of Gilaneh rice in split-plot experiments based on a randomized complete block design with three replications. Experimental treatments were irrigation intervals (flood irrigation and irrigation at 10 days) as the main factor and different levels of nitrogen (0, 60, and 120 kg ha⁻¹) and potassium (0, 80 and 160 kg ha⁻¹) fertilizers as a subfactor. Results showed that WUE and proline content increased by changing the moisture regime from flood irrigation to 10 days in all levels of fertilizers. The highest WUE (0.764 kg m⁻³) was observed in the treatment of N fertilizer of 60 kg ha⁻¹ with 160 kg ha⁻¹ of K fertilizer in the 10-day irrigation. The highest plant proline content (16.3 mg g⁻¹ FW) was observed in 160 kg ha⁻¹ of K fertilizer during 10-day irrigation. On the other hand, relative water content, chlorophyll a and b contents, carotenoids, maximum leaf area, and leaf area duration decreased with drought stress at all fertilizer levels. At the stress level, however, the application of fertilizers, in particular N fertilizer treatment, led to improvements in these traits. Given the scarcity of water resources in the country, therefore, WUE and other inputs can be improved in such strategic crops as rice with proper management of plant nutrition.

使用肥料管理植物营养是应对干旱和提高稻田水分生产率的一种方法。因此，本研究的目的是在基于三个重复的完全随机区组设计的地块试验中，研究氮，钾肥和干旱胁迫对吉兰水稻的水分利用效率（WUE）和生理特性的影响。实验处理方法是以灌溉间隔（洪水灌溉和10天灌溉）为主要因素，以及不同水平的氮（0、60和120 kg ha ^-1）和钾（0、80和160 kg ha ^-1））作为次要因素。结果表明，在所有水平的肥料中，将水分状态从洪水灌溉改变为10天，WUE和脯氨酸含量都会增加。在为期10天的灌溉中，在60 kg ha ^-1的氮肥和160 kg ha ^-1的钾肥的处理中观察到最高的WUE（0.764 kg m ^-3）。在160 kg ha ^-1中观察到最高的植物脯氨酸含量（16.3 mg g ^-1 FW）10天灌溉期间施用钾肥。另一方面，在所有肥料水平下，相对水分，叶绿素a和b含量，类胡萝卜素，最大叶面积和叶面积持续时间均随干旱胁迫而降低。然而，在压力水平上，肥料的施用，特别是氮肥的施用，导致这些性状的改善。因此，鉴于该国水资源的匮乏，可以通过适当管理植物营养来改善水稻等战略作物的WUE和其他投入。