In vitro sensitivity of Clarireedia, Fusarium and Microdochium isolated from grasses to commonly used fungicides

Authors: GAGKAEVA, T - The All Russian Research Institute For Animal Health (ARRIAH); ORINA, A - The All Russian Research Institute For Animal Health (ARRIAH); GAVRILOVA, O - The All Russian Research Institute For Animal Health (ARRIAH); USOLTSEVA, MARINA - Botaniska Analysgruppen; Crouch, Jo Anne; NORMANN, KAIN - Asbjørn Nyholt; ENTWISTLE, KATE - National Turfgrass Federation; TORP, TORFINN - Norwegian Institute Of Bioeconomy Research(NIBIO); ESPEVIG, TATSIANA - Norwegian Institute Of Bioeconomy Research(NIBIO)

Submitted to: International Turfgrass Society Research Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/30/2022
Publication Date: 5/10/2022
Citation: Gagkaeva, T.Y., Orina, A.S., Gavrilova, O.P., Usoltseva, M., Crouch, J.A., Normann, K., Entwistle, K., Torp, T., Espevig, T. 2022. In vitro sensitivity of Clarireedia, Fusarium and Microdochium isolated from grasses to commonly used fungicides. International Turfgrass Society Research Journal. 14:972-980. https://doi.org/10.1002/its2.139.
DOI: https://doi.org/10.1002/its2.139

Interpretive Summary: Dollar spot diseases affecting turfgrass on golf courses and lawns cause millions of dollars of damage globally each year. Until recently, dollar spot was not known in Nordic countries, possibly due to the region's unique climate. Since the turfgrass industry in Nordic countries rarely uses chemical pesticides, dollar spot is proving very difficult to control in the region, and information is needed to help manage the disease. In this research we tested whether different samples of the dollar spot fungi and two additional turfgrass pathogens were sensitive to fungicides labelled for use in Nordic countries. Overall, all of the dollar spot samples were sensitive to the tested fungicides, except for a product containing the active ingredient azoxystrobin. This research will be used by turfgrass pathologists, agronomists, extension agents, and golf course managers working to mitigate the effects of dollar spot disease in Nordic countries.

Technical Abstract: Reduction of fungicide use, maximizing of fungicide efficacy and minimizing the risk for fungicide resistance are the goals of chemical control of fungal diseases on golf greens. Microdochium nivale, Fusarium culmorum and Clarireedia spp. are common pathogenic fungi causing disease on golf greens in Nordic countries, sometimes simultaneously. Sensitivity to eight commonly used fungicides was tested for these three fungal pathogens using in vitro fungicide toxicity assays. Sensitivity to the tested fungicides varied significantly among the fungal species. Sensitivity of M. nivale to all tested fungicides was high, with the exception of tebuconazole. Clarireedia spp. isolates tested in this study showed high sensitivity to the tested fungicides, except for azoxystrobin.