The novel fungicide SYP-14288 acts as an uncoupler against Phytophthora capsici

• Published in: Pesticide biochemistry and physiology Vol. 147; pp. 83 - 89
• Main Authors: Wang, Zhiwen, Ni, Xiaoxia, Peng, Qin, Hou, Yanhua, Fang, Yuan, Mu, Wenjun, Liu, Changling, Liu, Pengfei, Liu, Xili
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.05.2018
• Subjects: Adenosine Triphosphate - biosynthesis; Adenosine Triphosphate - pharmacology; ATP synthesis; Capsicum - microbiology; Fluazinam; Fungicides, Industrial - pharmacology; Mitochondria - drug effects; Mitochondria - metabolism; Oxidative Phosphorylation - drug effects; P. capsici; Phytophthora - drug effects; Phytophthora - growth & development; Phytophthora - metabolism; Reproduction, Asexual - drug effects; Respiration; SYP-14288; Uncoupler; Uncoupling Agents - pharmacology; P. capsici; ATP synthesis; Uncoupler; Fluazinam; SYP-14288; Respiration
• ISSN: 0048-3575; 1095-9939
• DOI: 10.1016/j.pestbp.2018.01.014

SYP-14288 is a novel fungicide developed by the Shenyang Research Institute of Chemical Industry in China. Although preliminary studies indicate that SYP-14288 is highly effective against 32 important plant pathogens belonging to a range of taxonomic groups, its mode of action remains unknown. In this study, we documented that SYP-14288 has excellent activity against all of the asexual life stages of the plant-pathogenic oomycete Phytophthora capsici, and is especially effective in blocking cyst germination and other life stages that require high energy consumption. In assays designed to determine the fungicide's mode of action, addition of ATP reduced SYP-14288 inhibition of P. capsici, which suggested that SYP-14288 inhibits ATP synthesis of the pathogen. This inference was confirmed in that treatment with SYP-14288 sharply reduced the ATP content in P. capsici. The respiration rate of P. capsici was positively correlated with the concentration of SYP-14288 or of the fungicide fluazinam (an uncoupler of oxidative phosphorylation), but increases in respiration were greater with SYP-14288 than with fluazinam. These results indicate that SYP-14288 is a promising fungicide that functions as an uncoupler of oxidative phosphorylation. [Display omitted] •Biochemical activity of SYP-14288 on Phytophthora capsici was elucidated.•Activity of SYP-14288 on different asexual life stages of P.capsici was determined.•The protocol to extract mitochondria from P.capsici and its activity analysis method were established.