|Grunwald, Niklaus - Nik|
Submitted to: The Digger
Publication Type: Popular Publication
Publication Acceptance Date: 9/16/2008
Publication Date: 12/1/2009
Citation: Parke, J., Grunwald, N.J., Lewis, C. 2009. Tracing the path of pathogens: an ongoing study evaluates the systems approach for managing Phytophthora diseases in nurseries. Digger. 12:43-51. Interpretive Summary:
Technical Abstract: Almost every nursery grower is familiar with the plant pathogen Phytophthora (from the Greek, meaning “plant destroyer”). Phytophthora species cause some of the most damaging nursery crop diseases nationwide, including root rot, dieback, leaf blight and shoot blight. These pathogens do more than cause crop losses in nurseries. They reduce plant quality and undermine customer confidence in nursery products. In a study, we are using a systems approach to determine sources of contamination in nurseries. This approach is modeled after the HACCP (Hazard Analysis of Critical Control Points) strategy in use by the food industry to ensure that foods do not become contaminated during processing. In our systems approach research, we examine a nursery’s entire production system to determine where Phytophthora is in order to determine how it is getting there and how we can get rid of it. Our goal has been to identify Critical Control Points (CCPs) in the production system, that is, points at which a significant hazard of contamination can be controlled. Although the approach could be applied to any pest or disease, Phytophthora makes a good model for this study because the genus includes waterborne, soilborne, and airborne pathogens. If these sources of Phytophthora are eliminated, it is likely that many other pathogens will also be reduced. Here we report on the findings obtained by applying the HACCP approach to four commercial nurseries. Although the study is still underway, the systems approach has already been effective in identifying sources of Phytophthora contamination in nurseries and advising growers on management practices that will reduce disease.