期刊
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
卷 197, 期 -, 页码 -出版社
ACADEMIC PRESS INC ELSEVIER SCIENCE
DOI: 10.1016/j.ecoenv.2020.110593
关键词
Melatonin; Nickel toxicity; Secondary metabolites; Tomato; Antioxidant defense; Redox homeostasis; Phytoremediation
资金
- National Natural Science Foundation of China [31801902]
- China Earmarked Fund for Modern Agro-industry Technology Research System [CARS-23-B12]
- Jiangsu Province Scientific and Technological Achievements into Special Fund [BE2017701]
Arable land contamination with nickel (Ni) has become a major threat to worldwide crop production. Recently, melatonin has appeared as a promising stress-relief substance that can alleviate heavy metal-induced phytotoxicity in plants. However, the plausible underlying mechanism of melatonin function under Ni stress has not been fully substantiated in plants. Herein, we conducted an experiment that unveiled critical mechanisms in favor of melatonin-mediated Ni-stress tolerance in tomato. Ni stress markedly inhibited growth and biomass by impairing the photosynthesis, photosystem function, mineral homeostasis, root activity, and osmotic balance. In contrast, melatonin application notably reinforced the plant growth traits, increased photosynthesis efficiency in terms of chlorophyll content, upregulation of chlorophyll synthesis genes, i.e. POR, CAO, CHL G, gas exchange parameters, and PSII maximum efficiency (Fv/Fm), decreased Ni accumulation and increased mineral nutrient homeostasis. Moreover, melatonin efficiently restricted the hydrogen peroxide (H2O2) and superoxide radical production and increased RBOH expression and restored cellular integrity (less malondialdehyde and electrolyte leakage) through triggering the antioxidant enzyme activities and modulating AsA-GSH pools. Notably, oxidative stress was effectively mitigated by upregulation of several defense genes (SOD, CAT, APX, GR, GST, MDHAR, DHAR) and melatonin biosynthesis-related genes (TDC, T5S, SNAT, ASMT). Besides, melatonin treatment enhanced secondary metabolites (phenols, flavonoids, and anthocyanin) contents along with their encoding genes (PAL, CHS) expression, and these metabolites potentially restricted excess H2O2 accumulation. In conclusion, our findings deciphered the potential functions of melatonin in alleviating Ni-induced phytotoxicity in tomato through boosting the biomass production, photosynthesis, nutrient uptake, redox balance, and secondary metabolism.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据