Methyl jasmonate enhances rice tolerance to alkaline stress via the auxin pathway
Chun-Lan Chen,
Di Wu,
Qian-Kun Li,
Xiao-hu Liu,
Xu-Guang Niu,
Guo-Xian Zhang,
Yong-Yong Zhang,
Hui Zhang,
Chang-Jie Jiang
Affiliations
Chun-Lan Chen
College of Land and Environment, Shenyang Agricultural University, Shenyang 110866, Liaoning, China
Di Wu
College of Land and Environment, Shenyang Agricultural University, Shenyang 110866, Liaoning, China; Pratacultural College, Inner Mongolia University for Nationalities, Tongliao 028000, Innei Mongolia, China
Qian-Kun Li
College of Land and Environment, Shenyang Agricultural University, Shenyang 110866, Liaoning, China
Xiao-hu Liu
College of Land and Environment, Shenyang Agricultural University, Shenyang 110866, Liaoning, China
Xu-Guang Niu
College of Land and Environment, Shenyang Agricultural University, Shenyang 110866, Liaoning, China
Guo-Xian Zhang
College of Land and Environment, Shenyang Agricultural University, Shenyang 110866, Liaoning, China
Yong-Yong Zhang
College of Land and Environment, Shenyang Agricultural University, Shenyang 110866, Liaoning, China
Hui Zhang
College of Land and Environment, Shenyang Agricultural University, Shenyang 110866, Liaoning, China; Corresponding authors.
Chang-Jie Jiang
Rice Research Institute, Shandong Academy of Agricultural Sciences, Jinan 250100, Shandong, China; Corresponding authors.
Soil alkalization is a major challenge for global crop production. This study reveals a novel defense mechanism in rice seedlings against alkaline stress, involving methyl jasmonate (MeJA) and auxin pathways. Under alkaline stress (15 mM Na2CO3), rice seedlings exhibited elevated levels of endogenous MeJA and upregulation of JA-responsive genes. Pre-treatment with MeJA (50 µM) significantly improved seedling survival, growth, and mitigated root damage under alkaline stress. This treatment also upregulated genes associated with cell death suppression (OsBI1) and stress tolerance (OsJRL, OsNAC). Notably, MeJA pre-treatment increased auxin (indole-3-acetic acid, IAA) levels in roots, and upregulated genes involved in IAA synthesis (OASA1, OASA2) and auxin signaling (Aux/IAA, ARFs). Blocking auxin transport with N-1-naphthylphthalamic acid intensified root damage under alkaline stress and diminished the protective effect of MeJA. These results highlight the crucial role of MeJA-induced activation of auxin pathway in enhancing rice tolerance to alkaline stress, and provide valuable insights for developing strategies to improve crop resilience in alkaline soils.
