| Abstract: | Objective] The aim of this study is to investigate the cotton differential metabolites in the interaction between Verticillium dahliae and cotton plant, and to explore new clues for the further study on the defense mechanism of cotton against V. dahliae. Method] To obtain the cotton root, stem and leaf samples of the pathogen treated and healthy controls, the upland cotton cultivar CCRI 24 was selected as tested cotton material in this paper, and inoculated with V. dahliae conidia or sterile water by injuring root at the 2-true-leaf stage. The 70% (volume fraction) methanol extracts of these samples were separated and detected by ultra-performance liquid chromatography-electrospray ionization-mass spectrometry (UPLC-ESI-MS), and the metabolite data were obtained by the online XCMS software. Through multivariate statistics and student’s t-test, the differential metabolites were investigated. The types of metabolites were putatively identified based on the comparison of the experimental molecular mass and the monoisotopic accurate molecular mass of cotton metabolites. Result] The efficiency of negative ion mode was higher than that of positive ion detection mode in the cotton metabolites in UPLC-ESI-MS analysis. 576 ions mainly distributed in cotton root were found in the cotton seedling tissues including root, stem and leaf, which were the distinguished differential metabolites between V. dahliae treatment and healthy control. Among them, 77 ions were identified as sesquiterpenoids, diterpenoids, flavonoids, carbohydrates, aliphatics and phenols. In addition to sesquiterpenes, 17 compounds, including caffeic acid, astragalin, isoastragalin, dillenetin, ent-catechin, gossypetin 8-rhamnoside, gossypicyanin, herbacetin 7-glucoside, leucocyanidin, quercetin 3'-glucoside, quercetin 3-glucoside, quercetin 7-glycosides, α,2',3,3',4,4',6-heptahydroxychalcone 2'-glucoside, melibiose, sucrose, sucrose 6-phosphate and 1-tetratriacontanol, had not been reported in the literatures on the interaction between V. dahliae and cotton, which may be the novel pathogenesis-related metabolites on cotton Verticillium wilt. Conclusion] The putative pathogenesis-related metabolites of cotton Verticillium wilt may play an important role in the interaction of cotton defense against V. dahliae, which provides an important clue for exploring the new resistant mechanism of cotton to Verticillium wilt. |
