How do we know if plants in our nursery have Phytophthora? Detection methods and an integrated approach to monitoring

Abstract

A Phytophthora cactorum-infected nursery crop of Ceanothus thyrsiflorus was used to evaluate three Phytophthora monitoring methods. The Phytophthora detection level of three non-destructive sampling methods was quantified and compared to the detection level of destructive sampling. Non-destructive methods were (a) composite soil/root samples, pear-baited, (b) effluent samples, pear-baited, and (c) Agdia ImmunoStrip tests run on root samples. Time and expense of each method were also tracked. The baited soil/root sample method was the least labor intensive and most cost-effective method to test a large number of plants at our nursery. It also allows for species-level identification of Phytophthora, and has no risk of false positives. But detection level was 60%, so we have decided to combine it with destructive sampling, for an integrated monitoring approach.

Parent Publication

• Proceedings of the sudden oak death sixth science symposium

Citation

Conforti, Christa. 2017. How do we know if plants in our nursery have Phytophthora? Detection methods and an integrated approach to monitoring. 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: 65.