ABSTRACT
Sulphur coated urea increases drought tolerance in rice by improving photosynthetic efficiency, antioxidant performance, osmolyte synthesis, and nitrogen use efficiency

Muhammad Umer Chattha1 , Bisma Bisma1, Imran Khan1* , Muhammad Bilal Chattha2, Muhammad Talha Aslam1, Jameel M. Al-Khayri3*, Othman Al-Dossary3, Bader Alsubaie3, Mohammed I. Aldaej3, and Mustafa I. Almaghasla4
 
Drought stress (DS) significantly threatens crop productivity and global food security. The intensity of DS is continuously soaring due to climate change, which is causing a substantial reduction in plant productivity. Coated fertilizers emerged as an excellent strategy to improve crop productivity and reduce the toxic effects of abiotic stresses. Thus, this study determined the role of coated urea fertilizers in mitigating DS in rice (Oryza sativa L.) plants. The experiment comprised different DS levels: Control (100% field capacity: FC), 70% FC, and 50% FC; and different types of coated urea: Control, normal urea (NU), Zn-coated urea (ZCU), S-coated urea (SCU). Drought stress decreased grain yield by 43.7%, enhanced electrolyte leakage, hydrogen peroxide and malondialdehyde (+151%, +105% and +217%, respectively), and reduced chlorophyll-a, total soluble proteins and free amino acids by -84%, -85% and -69%, respectively. However, SCU application in DS augmented grain yield by ~46%, boosted ascorbic acid activity (+119%) and agronomic N use efficiency (67.12%). Therefore, applying SCU could be an effective strategy for mitigating the adverse impacts of drought and enhancing rice productivity.
Key words: Antioxidant, coated urea, field capacity, nitrogen use efficiency, Oryza sativa, yield.
1University of Agriculture Faisalabad, Department of Agronomy, Faisalabad 38040, Pakistan.
2University of the Punjab, Faculty of Agricultural Sciences, Lahore 54590, Pakistan.
3King Faisal University, College of Agriculture and Food Sciences, Department of Agricultural Biotechnology, Al-Ahsa 31982, Saudi Arabia.
4King Faisal University, College of Agriculture and Food Sciences, Plant Pests and Diseases Unit, Al-Ahsa 31982, Saudi Arabia.
*Corresponding authors (drimran@uaf.edu.pk; jkhayri@kfu.edu.sa)