Activity of Larrea tridentata (D.C.) Coville L. Extracts and chitosan against fungi that affect horticultural crops
The antifungal activity of gobernadora [Larrea tridentata (D.C.) Coville (L.)] hydrosoluble resin extract and chitosan solutions (Ch), alone and in combination, were investigated in vitro for their bioactivity against the fungi Botrytis cinerea, Colletotrichum coccodes and Fusarium oxysporum f. sp. lycopersici that were isolated from greenhouse roses, potatoes and tomatoes from commercial plots, respectively, and later purified. Both bioproducts demonstrated their fungicidal effect at 1000 and 2000 ì l·liter-1; however, when they were combined they exhibited synergistic fungicidal activity. These preliminary results indicate that L. tridentata hydrosoluble resin extract or the combination L-Ch could be considered as potential agrochemicals of low environmental impact for use as organic fungicides; however, further work is needed before this application could be used commercially. To the best of our knowledge, this is the first time that a mixture of L. tridentata and chitosan has been reported acting as antifungal compound.