There has been some questions on checking irrigation ponds for phytophthora where growers are planning to plant watermelon and other vegetables that could be susceptible to phytophthora.
Phytopthora is a fungal disease but not a true fungi. It is a water mold (Ooomycete). It survives for a long time in the soil and water and is tolerable of extreme environmental conditions such as cold weather. It also has a wide host range.
Here is a link to an APS (American Phytopathological Society) article on this disease in relation to cucurbits. https://www.apsnet.org/edcenter/disandpath/oomycete/pdlessons/Pages/Phytophthora.aspx
We have a plastic container with holes drilled in it, and floating aids attached that allow flotation while water infiltrates the container. Any susceptible host to phytophthora can be used in the container as bait. We typically like to use eggplant, and the fruit holds up pretty well in the pond for a few days.
Water temperatures are warming now, so now is a good time to call us on checking some if you plan to irrigate this way and are planting a susceptible host like cucurbit vegetables. We typically allow it to sit for at least three days. We take the bait to the lab in Tifton to see if phytophtora can be found after further testing.
Phytopthora does not survive deep down, so this is mainly for surface water irrigation. Please give us a call if you have further questions, or would like a pond checked.