Location: Horticultural Crops Research
Project Number: 5358-22000-039-15
Start Date: Sep 19, 2013
End Date: Sep 30, 2016
All research will be conducted in two important host-pathogen systems representative of typical PNW production using both container and field grown systems. The following two hosts with two pathogens in each group will be used as the central experimental system: (1) Rhododendron host & Phytophthora/Pythium pathogens; and (2) Japanese maple host & Verticillium/Phytophthora pathogens. Objective 1: Development of novel and rapid assays for pathogen detection. We will develop assays for rapid detection of Phytophthora, Pythium, Verticillium and select beneficial fungi at the genus and/or species level. We will use loop mediated isothermal amplification (LAMP) to detect pathogen DNA. LAMP is a technique of DNA amplification that does not rely on traditional PCR or thermal cycling where instead amplification is conducted at a set temperature typically between 60-65C. We will initially focus on the ITS and cox spacer regions for development of assays as these are well-characterized diagnostic regions. Objective 2: Characterization of the major plant pathogens in commercial nursery production systems including Pythium, Phytophthora, and Verticillium We will survey species in the plant pathogen genera Pythium, Phytophthora, and Verticillium, which are the most important pathogens of the soil disease complex on maple and rhododendron in the PNW. Briefly, we will systematically sample the rhizosphere and roots to identify dominant pathogen species. This is particularly challenging for the genus Pythium, where little work has been done to identify important species in nursery production. Objective 3. Characterization of the roles soil fungal communities play in nutrient cycling and soil health The most prevalent plant pathogen species will be studied further to determine how soil health, and particularly nutrient cycling, microbial community structure and pathogen species affect soil health and disease development. Replicated, factorial experiments will be conducted to assess effect of nutrient management on soil health.