Diferenciação de espécies crípticas de fungos do gênero Fusarium causadores de podridão do pedúnculo do melão (Cucumis melo L.): uma abordagem em fingerprinting lipídico via ESI-QTOF-MS

Abstract

Melon is one of the cucurbits with great nutritional value appreciated worldwide, but its production is subject to several problems at the post-harvest level. Contamination of the fruit by fungi of the genus Fusarium can cause rot capable of compromising its consumption and consequently its commercialization. Cryptic species of fungi of this genus have become a challenge in the process of identification and control of diseases in melons due to the great similarity that exists at the morphological level. In order to promote a rapid identification and differentiation of cryptic species of phytopathogens in melon, this work used high resolution mass spectrometry together with univariate and multivariate analysis methods, for the pilot study of the possibility of differentiating lipid profiles of isolates of fungi of the Fusarium equiseti-incarnatum species complex, in front or not of healthy melon samples. The obtained data were able to distinguish the isolates belonging to the same species complex from a lipid fingerprinting pattern, indicating lipids candidate for biomarkers responsible for differentiating the isolates and which remained distinguishable after joint analysis with the lipid profile of Cucumis melo L. The statistically relevant lipids obtained from analyzes by PLS-DA, VIP and ANOVA one-way were categorized as glycerophospholipids (GP) and sphingolipids (SP), using LIPID MAPS® as a database. This study reports the first application of lipid fingerprinting by flow injection analysis in mass spectrometry for the differentiation of cryptic species of melon phytopathogenic fungi from a robust and reproducible analytical methodology combined with chemometric methods.