Modern fungicides will remain an important tool in the management of plant diseases, in particular on high-value commodities. Fungal pathogens have never developed resistance to the older purely protective fungicides and these fungicides are, thus, still available. They are, however, non-specific, must be applied at high-use rates and are not considered valuable in IPM production systems. Repeated outbreaks of resistance to modern fungicides have prompted many growers to revert to these old materials. SMOR will alleviate this problem in the environmentally sound management of crops.
impact statement issue
The project was developed out of our long-term research on fungicide resistance and modes of action. Methods and approaches employed were population studies, risk assessments of new fungicide classes with state-of-the-art tools of molecular biology. The results of this work has contributed to basic research. It was also realized that previous resistance prediction tools were too coarse to protect the majority of growers from unexpected crop losses caused by resistance. The introduction of SMOR as a service and as a concept will allow growers to manage their diseases with minimal risk of control failures. Growers of high-value crops produced for the profitable fresh market for fruits and vegetables are interested in this service.
impact statement response
The development of SMOR necessitated the development of simple yet quantitative test procedures and the development of a database that would signal the status of fungal populations with regard to their level of resistance. The development work involved the participation of apple growers in NY, WV and the New England States. Result were continuously communicated to participating growers in technical grower-targeted extension material and at grower meetings.
impact statement summary
Many plant pathogenic fungi have developed resistance against modern and IPM-compatible fungicides, and some pathogens such as apple scab and multiple resistance to various unrelated classes. The fact that growers of fruits and vegetables are not aware of the status of resistance development at their own production sites, severe economic losses are frequently incurred. To prevent such crop losses pro-actively, we have developed the concept of site-specific management of resistance (SMOR). The status of resistance is tested for fungal populations at distinct tree fruit orchards for all four classes of modern fungicides currently available to growers. This information assists growers in their design of disease management without risking the unexpected outbreak of resistance. Work was funded by apple growers, the chemical industry and by USDA (NE-IPM). We have completed the research necessary for method development and data recruitment and will offer these tests as a service to growers.
