AUTHOR=Spinelli Veronica , Brasili Elisa , Sciubba Fabio , Ceci Andrea , Giampaoli Ottavia , Miccheli Alfredo , Pasqua Gabriella , Persiani Anna Maria 

TITLE=Biostimulant Effects of Chaetomium globosum and Minimedusa polyspora Culture Filtrates on Cichorium intybus Plant: Growth Performance and Metabolomic Traits

JOURNAL=Frontiers in Plant Science

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.879076

DOI=10.3389/fpls.2022.879076

ISSN=1664-462X

ABSTRACT=<p>In this study, we investigated the biostimulant effect of fungal culture filtrates obtained from <italic>Chaetomium globosum</italic> and <italic>Minimedusa polyspora</italic> on growth performance and metabolomic traits of chicory (<italic>Cichorium intybus</italic>) plants. For the first time, we showed that <italic>M. polyspora</italic> culture filtrate exerts a direct plant growth-promoting effect through an increase of biomass, both in shoots and roots, and of the leaf area. Conversely, no significant effect on morphological traits and biomass yield was observed in <italic>C. intybus</italic> plants treated with <italic>C. globosum</italic> culture filtrate. Based on <sup>1</sup>H-NMR metabolomics data, differential metabolites and their related metabolic pathways were highlighted. The treatment with <italic>C. globosum</italic> and <italic>M. polyspora</italic> culture filtrates stimulated a common response in <italic>C. intybus</italic> roots involving the synthesis of 3-OH-butyrate through the decrease in the synthesis of fatty acids and sterols, as a mechanism balancing the NADPH/NADP<sup>+</sup> ratio. The fungal culture filtrates differently triggered the phenylpropanoid pathway in <italic>C. intybus</italic> plants: <italic>C. globosum</italic> culture filtrate increased phenylalanine and chicoric acid in the roots, whereas <italic>M. polyspora</italic> culture filtrate stimulated an increase of 4-OH-benzoate. Chicoric acid, whose biosynthetic pathway in the chicory plant is putative and still not well known, is a very promising natural compound playing an important role in plant defense. On the contrary, benzoic acids serve as precursors for a wide variety of essential compounds playing crucial roles in plant fitness and defense response activation. To the best of our knowledge, this is the first study that shows the biostimulant effect of <italic>C. globosum</italic> and <italic>M. polyspora</italic> culture filtrates on <italic>C. intybus</italic> growth and metabolome, increasing the knowledge on fungal bioresources for the development of biostimulants.</p>