2019 ASHS Annual Conference

Anthracnose fruit rot (Colletotrichum gloeosporioides) is a particularly devastating fungal disease of many fruit crops that causes millions of dollars in damage every year. Current methods of anthracnose control are heavily reliant on the thorough application of several fungicides. There is great concern over the continued use of current anti-anthracnose compounds due to the appearance of numerous fungicide-resistant strains. Examples abound of instances where overapplication of conventional fungicides led to the rapid emergence of highly resistant anthracnose variants against which growers had no defense- as the case of the blueberry variety 'Flicker' in Florida demonstrates. The development of novel anti-anthracnose fungicidal compounds is one way to combat the rise of new anthracnose strains displaying resistance to currently used fungicides. To aid in the search for such compounds, we examined the potential of actinomycete strains from Florida's unique sand pine scrub ecoregion to produce anti-anthracnose natural compounds. Preliminary screening of over 300 isolates revealed several with activity against an aggressive strain of anthracnose fruit rot. This activity manifested itself as inhibiting the germination of C. gloeosporioides conidia, halting the spread of C. gloeosporioides mycelia, or doing both. Further research going forward includes isolating the fungicidal compounds of interest from the producing strains and testing them for toxicity against humans and the environment.