Biological efficiency of polyphenolic extracts from pecan nuts shell (Carya Illinoensis), pomegranate husk (Punica granatum) and creosote bush leaves (Larrea tridentata Cov.) against plant pathogenic fungi

Bioactive compounds extracted from plants or agro-industrial residues have great potential as novel fungicide sources for controlling pathogenic fungi. In this study antifungal activity of polyphenolic extracts from Larrea tridentata leaves, Carya illinoensis shells and Punica granatum husk were evaluated in vitro against eight different plant pathogenic fungi and ten isolates of Fusarium oxysporum. Phenolic solutions of gallic and ellagic acids were also tested at different concentrations. The polyphenolic extracts tested have a high efficiency to inhibit the mycelial growth of Pythium sp., Colletotrichum truncatum, Colletotrichum coccodes, Alternaria alternata, Fusarium verticillioides, Fusarium solani, Fusarium sambucinum, and Rhizoctonia solani. L. tridentata polyphenolic extracts also efficiently inhibited the mycelial growth of eight out of ten F. oxysporum isolates. These results showed that the polyphenolic extracts tested possess antifungal activities against a broad spectrum of plant pathogenic fungi and could be used as potential antifungal agents for the control of fungal plant diseases.