Antagonistic Activity of Macrolepiota sp. CS185 against Post-Harvest Fungi of Fig Fruits (Ficus carica L.)

Abstract

Macrolepiota sp. CS185 is a basidiomycete with high potential as a biocontrol agent against various phytopathogenic fungi. Regardless of its pronounced potential as a post-harvest fungi biocontrol agent, its activity in tomato seedlings infected with Alternaria alternata has not been well studied. Thus, the present work aimed to evaluate the cultures and supernatants’ antagonistic activity against fig fruits’ post-harvest fungi and antifungal activity production kinetics. The culture antagonistic characteristics were assessed through multiple confrontations, the supernatant concentration effect, and the kinetics of antagonistic action. The multiple confrontations showed differences (p ≤ 0.05) among phytopathogens and over time, with Colletotrichum sp. 2 being the most susceptible. Based on the 9-day incubation profile, the treatment fractions supplemented with a 50% concentration of Macrolepiota sp. CS185 supernatants showed a higher inhibition percentage (%In). Except for Alternaria alternata 1 and 2, the rest of the isolates showed a similar decrease in antagonistic activity up to a certain extent over time. Among all tested strains, Colletotrichum sp. 2 was found with a higher susceptibility. Regarding the production kinetics of antagonistic activity, a triple interaction was observed between the phytopathogen, the age of the Macrolepiota sp. CS 185 culture, and incubation time. In addition, changes in the mycelium growth rate (p ≤ 0.05) along with the higher activity in the supernatants of 20 and 30 days were observed and suggested the production of multiple bioactive metabolites. These results indicate that Macrolepiota sp. CS185 produces antifungal metabolites at different times and could be a suitable candidate to control fig fruits’ post-harvest fungi issues.