Antifungal potential of Capsicum annuum var. glabriusculum on Moniliophthora roreri in response to fruit maturity and shading during fruit growth.

Moniliophthora roreri has significantly impacted cacao production in Latin America, including Mexico. Extracts of Capsicum annuum can inhibit its growth, although their effectiveness depends on fruit maturity and environmental conditions. In this study, the in vitro efficacy of methanolic extracts of immature and mature fruits of C. annuum var. glabriusculum from plants grown under 0, 35, and 70% shade was evaluated for its ability to inhibit mycelial growth (MG) and sporulation of M. roreri. The most effective treatment was selected and used in a field trial involving young fruits of three cacao genotypes in Tabasco, Mexico. Extracts of immature fruits of this chili pepper contain phenolic compounds that inhibit MG and sporulation of M. roreri both in vitro and in vivo, independently of shading during fruit growth. All treatments at a concentration of 2.5g/l delayed the onset of fungal growth and were highly effective in inhibiting MG and sporulation. In cacao fruit slices, the concentrated extract reduced fungal sporulation by more than 50%, with a second application on the third day. In the field, the antifungal efficacy of the extracts was greater than 50% when applied three days before fruit inoculation. The in vitro and in vivo efficacy of extracts from immature C. annuum var. glabriusculum fruits against M. roreri, regardless of shading, highlights its potential as a sustainable alternative for managing moniliasis in cacao plantations.