Skip to page content
USDA Forest Service
  
Treesearch

Research & Development Treesearch

 
Treesearch Home
About Treesearch
Contact Us
Research & Development
Forest Products Lab
International Institute of Tropical Forestry
Northern
Pacific Northwest
Pacific Southwest
Rocky Mountain
Southern Research Station
Help
 

Science.gov - We Participate


USA.gov  Government Made Easy


Global Forest Information Service

US Forest Service
P.O. Box 96090
Washington, D.C.
20090-6090

(202) 205-8333

You are here: Home / Search / Publication Information
Bookmark and Share

Publication Information

View PDF (146.0 KB bytes)

Title: Determining the amount of soilborne inoculum of Phytophthora ramorum within an Oregon tanoak forest

Author: Benemann, Christina; Parke, Jennifer;

Date: 2017

Source: Proceedings of the sudden oak death sixth science symposium. Gen. Tech. Rep. GTR-PSW-255. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station: 62.

Publication Series: General Technical Report (GTR)

   Note: This article is part of a larger document. View the larger document

Description:

Phytophthora ramorum continues to cause extensive mortality of tanoaks in southwestern Oregon. Effective management strategies have been developed based on our current understanding of the pathogen’s epidemiology. Local dispersal can occur either by canopy throughfall (“top-down”) or a ground splash (“bottom-up”) pathway. Although the “top-down” aspect of the disease cycle is well understood, the importance of infested soil and leaf litter as contributing factors to the spread of disease remains unclear. To elucidate the epidemiological importance of these “bottom-up” sources of inoculum, our study aims to (i) compare the amount of inoculum washed down through the canopy to that splashed up from the soil and litter, and (ii) to detect and quantify inoculum in relation to soil depth. Over the course of the rainy season, both rainwater and soil samples were periodically collected from within the Generally Infested Area in Brookings, Oregon.

To determine if the amount of soilborne inoculum is at least as much as that derived from throughfall, a tiered bucket design was set up under infested canopies at five different locations. One bucket was set on the ground to collect throughfall and another was placed into the ground to collect throughfall and any splash-up from the surrounding soil and litter. A third bucket was baited and used to detect the presence of P. ramorum in real time. To determine the distribution of inoculum in the soil profile, samples were taken at 5, 10, and 15 cm depths and subjected to baiting. DNA was extracted from rainwater in the unbaited buckets and soil from the 5 cm depth. Quantification of P. ramorum in these samples will be attempted with qPCR, which should detect differences that will indicate how inoculum from infested canopies and soil contribute to the inoculum pool in these forests.

This information will add to the existing knowledge of disease transmission biology in natural settings, which can inform management strategies aimed at minimizing the local spread of the disease.

Publication Notes:

  • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
  • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.

XML: View XML

Citation:


Benemann, Christina; Parke, Jennifer 2017. Determining the amount of soilborne inoculum of Phytophthora ramorum within an Oregon tanoak forest. In: Frankel, Susan J.; Harrell, Katharine M., tech. coords. Proceedings of the sudden oak death sixth science symposium. Gen. Tech. Rep. GTR-PSW-255. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station: 62.

 


 [ Get Acrobat ]  Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility

USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.