Muscodor brasiliensis sp. nov. produces volatile organic compounds with activity against Penicillium digitatum.

Endophytic fungi belonging to Muscodor genus are considered as promising alternatives to be used in biological control due to the production of volatile organic compounds (VOCs). The strains LGMF1255 and LGMF1256 were isolated from the medicinal plant Schinus terebinthifolius and, by morphological data and phylogenetic analysis, identified as belonging to Muscodor genus. Phylogenetic analysis suggests that strain LGMF1256 is a new species, which is herein introduced as Muscodor brasiliensis sp. nov. The analysis of VOCs production revealed that compounds phenylethyl alcohol, α-curcumene, and E (ß) farnesene until now has been reported only from M. brasiliensis, data that supports the classification of strain LGMF1256 as a new species. M. brasiliensis completely inhibited the phytopathogen P. digitatum in vitro. We also evaluated the ability of VOCs from LGMF1256 to inhibit the development of green mold symptoms by inoculation of P. digitatum in detached oranges. M. brasiliensis reduced the severity of diseases in 77%, and showed potential to be used for fruits storage and transportation to prevent the green mold symptoms development, eventually reducing the use of fungicides.

Diaporthe endophytica and D. terebinthifolii from medicinal plants for biological control of Phyllosticta citricarpa.

The citrus industry is severely affected by citrus black spot (CBS), a disease caused by the pathogen Phyllosticta citricarpa. This disease causes loss of production, decrease in the market price of the fruit, and reduction in its export to the European Union. Currently, CBS disease is being treated in orchards with various pesticides and fungicides every year. One alternative to CBS disease control without harming the environment is the use of microorganisms for biological control. Diaporthe endophytica and D. terebinthifolii, isolated from the medicinal plants Maytenus ilicifolia and Schinus terebinthifolius have an inhibitory effect against P. citricarpa in vitro and in detached fruits. Moreover, D. endophytica and D. terebinthifolii were transformed by Agrobacterium tumefaciens for in vivo studies. The transformants retained the ability to control of phytopathogenic fungus P. citricarpa after transformation process. Furthermore, D. endophytica and D. terebinthifolii were able to infect and colonize citrus plants, which is confirmed by reisolation of transformants from inoculated and uninoculated leaves. Light microscopic analysis showed fungus mycelium colonizing intercellular region and oil glands of citrus, suggesting that these two new species are capable of colonizing citrus plants, in addition to controlling the pathogen P. citricarpa.