6 Apr 2018
Phytophthora Communities in a Western Oregon (USA) River
Redekar, N., Eberhart, J., and J.L. Parke (Oregon State University)
One source of oomycete (Phytophthora and Pythium) contamination in nurseries and greenhouses is the use of untreated water from ponds and rivers. Next generation DNA sequencing was used to detect species of Phytophthora and Pythium in irrigation water originating from a river. Research highlights: 1) Pythium and Phytophthora are the most abundant oomycete genera found in river water, 2) the oomycete species in river water fluctuate seasonally, 3) leaf baiting is the best method to detect active plant pathogens, particularly Phytophthora species, and 4) next generation sequencing technology is a very effective, sensitive and semi-quantitative method for detecting Phytophthora and Pythium in water or soil.
Take home message for growers: 1) surface water (rivers and ponds) are almost always contaminated with Phytophthora and Pythium species, 2) water can be tested using leaf baiting to determine if Phytophthora is present https://youtu.be/SJx7gzXyXoM 3) water should be disinfested before use in irrigation.
Poster IUFRO Redekar et al (724 KB)
19 Mar 2018
Slow Sand Filters
Pitton, B.J.L., Oki, L.R. (University of California Davis), White, S.A (Clemson University)
Slow sand filters (SSF) can provide high-quality water from untreated sources like irrigation runoff. SSFs consist of a sand bed with about three feet of water above that flows through the sand via gravity. A microorganism community develops on the sand that has the ability to remove plant pathogens, including water molds, viruses, bacteria, and fungi. Flow rates are approximately six inches per hour so they can occupy a large area if sizable volumes of water need to be treated. However, SSFs are simple to install and are fairly cheap to operate compared to other treatment technologies.
23 Jan 2018
Majsztrik, J., White, S.A. (Clemson University), and J.S. Owen, Jr. (Virginia Tech University)
Is my water clean enough or will it harm my plants? The question is simple, the answer is not. One of the most common methods of water treatment is physical screening. Typical physical filters include sand, mesh screen, disc, glass, or other substrates that serve as barriers to particulates. During physical screening, the materials in the filter serve as a barrier to stop particles (sediment) from moving through the filter. Learn more about these filters, and how to keep your plants safe from disease and chemicals that may be spread through recycled irrigation water.