Sun Yingying, Chen Jie, Wang Wei, Zhu Lizhong
College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, Zhejiang 310058, China.
College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, Zhejiang 310058, China; Ministry of Education Key Laboratory of Environment Remediation and Ecological Health, Zhejiang University, Hangzhou, Zhejiang 310058, China.
Environ Int. 2025 Jul;201:109553. doi: 10.1016/j.envint.2025.109553. Epub 2025 May 27.
Phthalate esters (PAEs) were ubiquitous in agricultural soils and could be metabolized after being absorbed by crops, posing significant implications for crop yield and quality. We hypothesize that monophthalates (mPAEs), the hydrolyzed products of PAEs, might mimic phytohormone jasmonic acid (JA) to activate the JA signaling pathway, therefore enhancing the defense towards pests and inhibiting the rice plant growth. Taking dibutyl phthalate (DBP) as a representative PAE, our study discovered that DBP exposure significantly induced JA-related outcomes including decreased larval weight (9.58-18.8%), and rice biomass (11.7-34.2%). Under the conditions where the JA content remained unchanged, monobutyl phthalate (MBP), the hydrolyzed product of DBP, triggered the JA signaling pathway, evidenced by significantly upregulated genes encoding coronatine insensitive 1 (COI1) (1.56-1.73 fold), jasmonate ZIM-domain (JAZ) (4.33-7.71 fold), MYC2 transcription factor (2.07-2.87 fold), and promoted phytoalexins production in downstream signaling. MBP conjugated with isoleucine, and the conjugate subsequently mimicked a JA bioactivator (JA-isoleucine conjugate) to occupy the binding site of COI1-JAZ co-receptor protein, thereby initiating the JA signaling pathway. These JA-related outcomes and mechanism were consistently evidenced in rice exposed to other four typical PAEs, and the aliphatic chain length of selected PAEs indicated a negative contribution to these observations. In this study, we discovered a unconventional mechanism through which the transformation metabolites of PAEs elicit pest defense while simultaneously inhibiting rice growth, providing insights into the risk assessment of PAEs on crop yields and quality.
邻苯二甲酸酯（PAEs）在农业土壤中广泛存在，被作物吸收后可被代谢，这对作物产量和品质具有重大影响。我们推测，PAEs的水解产物单邻苯二甲酸酯（mPAEs）可能模拟植物激素茉莉酸（JA）来激活JA信号通路，从而增强对害虫的防御并抑制水稻植株生长。以邻苯二甲酸二丁酯（DBP）作为代表性PAE，我们的研究发现，暴露于DBP会显著诱导与JA相关的结果，包括幼虫体重下降（9.58 - 18.8%）和水稻生物量下降（11.7 - 34.2%）。在JA含量保持不变的条件下，DBP的水解产物单丁基邻苯二甲酸酯（MBP）触发了JA信号通路，编码冠菌素不敏感1（COI1）的基因显著上调（1.56 - 1.73倍）、茉莉酸ZIM结构域（JAZ）基因显著上调（4.33 - 7.71倍）、MYC2转录因子基因显著上调（2.07 - 2.87倍）证明了这一点，并且MBP促进了下游信号通路中植保素的产生。MBP与异亮氨酸结合，该共轭物随后模拟JA生物激活剂（JA - 异亮氨酸共轭物）占据COI1 - JAZ共受体蛋白的结合位点，从而启动JA信号通路。在暴露于其他四种典型PAEs的水稻中，这些与JA相关的结果和机制得到了一致证明，所选PAEs的脂肪链长度对这些观察结果显示出负面影响。在本研究中，我们发现了一种非常规机制，通过该机制PAEs的转化代谢产物引发害虫防御，同时抑制水稻生长，这为评估PAEs对作物产量和品质的风险提供了见解。
