The Past, Present, and Future of Plant Activators Targeting the Salicylic Acid Signaling Pathway

作者：Misbah Naz, Dongqin Zhang, Kangcen Liao, Xulong Chen, Nazeer Ahmed, Delu Wang, Jing‐Jiang Zhou, Zhuo Chen · 发表于：Genes · 年份：2024 · DOI：10.3390/genes15091237 · 被引用次数：23 · 研究领域：Plant-Microbe Interactions and Immunity、Plant tissue culture and regeneration、Plant Stress Responses and Tolerance

Plant activators have emerged as promising alternatives to conventional crop protection chemicals for managing crop diseases due to their unique mode of action. By priming the plant's innate immune system, these compounds can induce disease resistance against a broad spectrum of pathogens without directly inhibiting their proliferation. Key advantages of plant activators include prolonged defense activity, lower effective dosages, and negligible risk of pathogen resistance development. Among the various defensive pathways targeted, the salicylic acid (SA) signaling cascade has been extensively explored, leading to the successful development of commercial activators of systemic acquired resistance, such as benzothiadiazole, for widespread application in crop protection. While the action sites of many SA-targeting activators have been preliminarily mapped to different steps along the pathway, a comprehensive understanding of their precise mechanisms remains elusive. This review provides a historical perspective on plant activator development and outlines diverse screening strategies employed, from whole-plant bioassays to molecular and transgenic approaches. We elaborate on the various components, biological significance, and regulatory circuits governing the SA pathway while critically examining the structural features, bioactivities, and proposed modes of action of classical activators such as benzothiadiazole derivatives, salicylic acid analogs, and other small molecules. In...