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Topsin-M: the new benomyl for mycorrhizal-suppression experiments
1Department of Natural Resource Ecology and Management, 008C Agricultural Hall, Oklahoma State University, Stillwater, Oklahoma 74078-6013, USA. gail.wilson@okstate.edu
Mycologia
|October 7, 2008
Summary
Topsin fungicide effectively suppresses arbuscular mycorrhizal fungi (AMF) colonization in grasses, offering a viable alternative to the unavailable benomyl for experimental research. It reduced biomass in some grasses, but fertilization mitigated this effect.
Area of Science:
- Agricultural Science
- Plant Pathology
- Mycology
Background:
- Benomyl, a common fungicide for arbuscular mycorrhizal fungal (AMF) suppression, is no longer manufactured.
- There is a need for effective alternatives to benomyl in experimental settings to control mycorrhizal fungi.
Purpose of the Study:
- To evaluate Topsin M (topsin) as a potential fungicide to suppress mycorrhizal symbiosis.
- To assess topsin's efficacy in both field and greenhouse experiments.
Main Methods:
- Topsin fungicide was applied to grasses Andropogon gerardii and Pascopyron smithii in controlled experiments.
- AMF colonization and plant biomass production were measured.
- The impact of nitrogen and phosphorus fertilization on biomass was also investigated.
Main Results:
- Topsin significantly reduced AMF colonization and plant biomass in Andropogon gerardii.
- Topsin reduced AMF colonization in Pascopyron smithii but did not significantly impact biomass.
- Fertilization with nitrogen and phosphorus compensated for biomass reduction caused by topsin.
Conclusions:
- Topsin M is a useful and successful alternative fungicide for suppressing mycorrhizal fungi in experimental systems where benomyl was previously used.
- Fertilization can counteract potential negative impacts of topsin on plant biomass.
