Potential of Myrothecium species as bioherbicides for giant salvinia (Salvinia molesta)

Authors: Weaver, Mark; SHEARER, JUDAY - Us Army Engineer Research And Dvelopment Center; Grodowitz, Michael; Boyette, Clyde

Submitted to: Journal of Aquatic Plant Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/5/2018
Publication Date: 6/14/2018
Citation: Weaver, M.A., Shearer, J.F., Grodowitz, M.J., Boyette, C.D. 2018. Potential of Myrothecium species as bioherbicides for giant salvinia (Salvinia molesta). Journal of Aquatic Plant Management. 56:120-122.

Interpretive Summary: Giant salvinia is an exotic, invasive floating weed that can be difficult to manage. We tested four fungal isolates (Myrothecium spp.) to determine if they were pathogens of giant salvinia. All four were virulent on giant salvinia and up to 70 percent reduction in biomass of giant salvinia was achieved in some treatments, supporting the possible role for plant pathogen-based biological control of giant salvinia.

Technical Abstract: Giant salvinia is an exotic, invasive floating weed that can be difficult to manage. We examined a previously described isolate of the Myrothecium verrucaria and three new isolates of Myrotheicum roridum for virulence against giant salvinia. These plant pathogens were grown on a standard medium, potato dextrose agar, or a defined Vogels-glucose agar and before applying to giant salivina in outdoor mesocosms with various adjuvants. Addition of spray adjuvants improved bioherbicidal efficacy, but the selection of adjuvant was not statistically significant. Up to 70 percent reduction in biomass of giant salvinia was achieved in some treatments, supporting the possible role for Myrothecium-based biological control of giant salvinia.