Open Access

ARTICLE

Melatonin Promotes Rice Seed Germination under Drought Stress by Regulating Antioxidant Capacity

by Luqian Zhang^1,#, Xilin Fang^1,#, Nan Yu¹, Jun Chen¹, Haodong Wang¹, Quansheng Shen¹, Guanghui Chen^2,*, Yue Wang^1,*

1 College of Agronomy, Hunan Agricultural University, Changsha, 410128, China
2 The Key Laboratory of Crop Germplasm Innovation and Resource Utilization of Hunan Province, Hunan Agricultural University, Changsha, 410128, China

* Corresponding Authors: Guanghui Chen. Email: ; Yue Wang. Email:
# These authors contributed equally to the work

(This article belongs to the Special Issue: Abiotic and Biotic Stress Tolerance in Crop)

Phyton-International Journal of Experimental Botany 2023, 92(5), 1571-1587. https://doi.org/10.32604/phyton.2023.025481

Received 15 July 2022; Accepted 06 December 2022; Issue published 09 March 2023

Abstract

Drought stress is a serious threat to the germination of plant seeds and the growth of seedlings. Melatonin has been proven to play an important role in alleviating plant stress. However, its effect on seed germination under drought conditions is still poorly understood. Therefore, we studied the effects of melatonin on rice seed germination and physiological characteristics under drought stress. Rice seeds were treated with different concentrations of melatonin (i.e., 0, 20, 100, and 500 μM) and drought stress was simulated with 5% polyethylene glycol 6000 (PEG6000). The results showed that 100 μM melatonin can effectively improve the germination potential, rate and index; the vigor index of rice seeds; and the length of the shoot and root. In addition, that treatment also increased the activity of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), and reduced the content of malondialdehyde (MDA). The grey relational grade between the shoot MDA content and the melatonin seed-soaking treatment was the highest, which could be useful for evaluating the effect of melatonin on drought tolerance. Two-way analysis of variance showed that the effect of single melatonin treatment on rice seeds was more significant than that of single drought stress and interaction treatment of drought and melatonin (p < 0.05). The subordinate function results showed that 100 μM melatonin significantly improved the germination and physiological indexes of rice seeds and effectively alleviated the adverse effects of drought stress on rice seedlings. The results helped to improve the understanding of the morphological and physiological involvement of melatonin in promoting seed germination and seedling development under drought stress.

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Keywords

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Supplementary Material

Supplementary Material File

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