Dr. University of Maryland eastern shore Princess Anne, Maryland
Body of Abstract: Plant diseases are considered as a major biological threat to agriculture and food production worldwide, leading to food shortages and significant economic losses. Synthetic fungicides still effectively protect crop plants against fungal pathogens. However, the emergence of resistant strains of fungal phytopathogens to these fungicides in addition to their potential risks to human health and environment has necessitated a search for new antifungal metabolites. The use of naturally sourced secondary metabolites from beneficial microorganisms have attracted great attention. In this sense, soil-dwelling actinomycetes are a treasure source for searching novel secondary metabolites with antibacterial, antifungal and antiviral activities. In current study, antibacterial activities of some soil Streptomyces spp. were tested against a panel of plant pathogenic fungi and fungus-like organisms. In total, six culture extracts from the actinomycetes strains demonstrated broad-spectrum antifungal activities against Botrytis cinerea, Colletotrichum viniferum, Didymella americana, Fusarium oxysporum, Fusarium solani, Geotrichum candidum, Mucor piriformis, Penicillium digitatumScleretinia sclerotionum, Rhizopus stolonifer, Phytophthora sojae, and Pythium aphanidermatum. Analysis of the culture extracts of the actinomycetes isolates using High-Resolution Mass Spectrometry (HR-MS) identified a novel class of antifungal metabolites with biocontrol potential against a broad-spectrum of fungal phytopathogens.