The Antimicrobial Peptide Thanatin Reduces Fungal Infections in Arabidopsis

We explored the antifungal activity of thanatin, a 21 amino acid synthetic peptide from the hemipteran spined soldier bug Podisus maculiventris, against the mycotoxin-producing plant pathogenic ascomycete Fusarium graminearum. In vitro germination assays showed complete inhibition of macroconidia germination and mycelia growth by >10 μm thanatin. Moreover, detached leaves of thanatin-expressing Arabidopsis thaliana plants displayed enhanced resistance towards colonization with F. graminearum. Consistent with this, the plants showed also enhanced resistance of detached leaves to colonization with Botrytis cinerea. The results demonstrate a potential of thanatin for use in plant protection.