Page Banner

United States Department of Agriculture

Agricultural Research Service

Related Topics

Research Project: Molecular diagnostics of Phytophthora Spp. from natural ecosystems

Location: Crop Improvement and Protection Research

2012 Annual Report


1a.Objectives (from AD-416):
To validate molecular diagnostic tools for identification of Phytophthora ramorum, the pathogen responsible for sudden oak death.


1b.Approach (from AD-416):
Two different molecular diagnostic techniques will be evaluated for their effectiveness in identifying Phytophthora species in infected plat tissue using samples collected from different regions of the USA. One procedure is a TaqMan real time PCR diagnostic marker that exhibits specificity at a genus level (it can identify if a Phytophthora spp. is present) in addition to a species level (different probes can differentiate P. ramorum or P. kernoviae from other species). The second procedure is for determination of mitochondrial haplotype of P. ramorum, which so far has been correlated with the nuclear genotype. The technique uses melt curve analysis to make the determination, which takes much less time than conventional techniques for genotype determinations.


3.Progress Report:

The agreement was established in support of objective 2 of the in house project, the goal being to develop molecular diagnostic tools for the identification of emerging diseases of vegetables and strawberries, and use these tools in the development of management strategies as alternatives to methyl bromide.

The objective of the project is to optimize and fully validate a new molecular diagnostic technique for Phytophthora spp. that was developed as part of project 5305-22000-12-06R, "Development of a systematic approach for marker selection in Phytophthora using mitochondrial genomic sequences." DNA from P. ramorum isolates obtained from California Department of Agriculture, Sacramento, Oregon State University and Pennsylvania State University have been sequenced to confirm their identification. A single tube, PCR-melt curve analysis technique for haplotype analyses of P. ramorum isolates is being developed. Communication on the project status is done with the granting agency by e-mail and submission of written yearly progress reports.


Last Modified: 9/10/2014
Footer Content Back to Top of Page