Brassinosteroid modulates ethylene synthesis and antioxidant metabolism to protect rice (Oryza sativa) against heat stress-induced inhibition of source‒sink capacity and photosynthetic and growth attributes

Faroza Nazir; Badar Jahan; Sarika Kumari; Noushina Iqbal; Mohammed Albaqami; Adriano Sofo; M Iqbal R Khan

doi:10.1016/j.jplph.2023.154096

Brassinosteroid modulates ethylene synthesis and antioxidant metabolism to protect rice (Oryza sativa) against heat stress-induced inhibition of source‒sink capacity and photosynthetic and growth attributes

J Plant Physiol. 2023 Oct:289:154096. doi: 10.1016/j.jplph.2023.154096. Epub 2023 Sep 19.

Authors

Faroza Nazir¹, Badar Jahan², Sarika Kumari¹, Noushina Iqbal¹, Mohammed Albaqami³, Adriano Sofo⁴, M Iqbal R Khan⁵

Affiliations

¹ Department of Botany, Jamia Hamdard, New Delhi-110062, India.
² Department of Botany, Aligarh Muslim University, Aligarh-202002, India.
³ Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
⁴ Department of European and Mediterranean Cultures: Architecture, Environment, Cultural Heritage (DiCEM), University of Basilicata, Via Lanera 20, 75100, Matera, MT, Italy.
⁵ Department of Botany, Jamia Hamdard, New Delhi-110062, India. Electronic address: [email protected].

PMID: 37776751
DOI: 10.1016/j.jplph.2023.154096

Abstract

This study presents an exploration of the efficacy of brassinosteroids (BRs) and ethylene in mediating heat stress tolerance in rice (Oryza sativa). Heat is one of the major abiotic factors that prominently deteriorates rice production by influencing photosynthetic efficiency, source‒sink capacity, and growth traits. The application of BR (0.5 mM) and ethylene (200 μl l^-1) either individually and/or in combination was found to alleviate heat stress-induced toxicity by significantly improving photosynthesis, source‒sink capacity and defense systems; additionally, it reduced the levels of oxidative stress markers and ethylene formation. The study revealed the positive influence of BR in promoting plant growth responses under heat stress through its interplay with ethylene biosynthesis and enhanced plant defense systems. Interestingly, treatment with the ethylene biosynthesis inhibitor aminoethoxyvinylglycine (AVG) substantiated that BR application to heat-stressed rice plants enhanced ethylene-dependent pathways to counteract the underlying adversities. Thus, BR action was found to be mediated by ethylene to promote heat tolerance in rice. The present study sheds light on the potential tolerance mechanisms which can ensure rice sustainability under heat stress conditions.