PhD Candidate in Plant Biology with a focus on secondary metabolites, particularly in plant wild relatives, as a means to enhance crop resistance to disease.
I am also intrigued by the evolutionary aspects of resistance in plants during crop domestication.
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Exploring the Antifungal Arsenal: Steroidal Glycoalkaloids in Wild Tomatoes for Enhanced Plant Defense
Steroidal glycoalkaloids (SGAs), prominent secondary metabolites in Solanaceae plants, exhibit antifungal properties exemplified by α-tomatine in cultivated tomatoes. While the main SGAs in cultivated tomatoes and their biosynthesis pathway are known, little is understood about SGAs in wild tomato species, particularly their diversity and antifungal potential. Our study aims to identify SGAs in 13 wild relatives of cultivated tomato and investigate their role in inhibiting various fungal strains, including tomato specialist pathogens (Fusarium oxysporum f.sp. lycopersici (MN25) and Cladosporium fulvum), endophytes (Fusarium oxysporum Fo47 v2.0), and generalist pathogens (Colletotrichum coccodes). We also ask whether in vitro antifungal activity correlates with in vivo defense against airborne (C. fulvum) and soilborne (MN25) pathogens.
Our findings reveal robust antifungal properties in leaf extracts of five wild tomato species against all tested strains, suggesting a conserved inhibitory effect within the tomato clade. We detected seven known SGAs in varying proportions in wild tomato leaf extracts, with α-tomatine, dehydrotomatine, and acetoxytomatine exhibiting significant negative correlations with fungal fitness traits. However, inoculation experiments with a soilborne pathogen indicate that higher SGA levels in wild tomato species may not completely prevent infection, possibly due to lower SGA concentrations in roots and stems compared to leaves. Ongoing research focuses on identifying further novel SGAs and elucidating the role of SGAs in defense against airborne pathogens.