07/21/05 Lesion nematode & annual cereals

Farm and Ranch July 21, 2005 After learning that something called the lesion nematode was limiting production in Australia in annual cereal crops, research began in the Pacific Northwest to see if the same phenomenon was occurring here. Richard Smiley of the Columbia Basin Agricultural Research Center in Pendleton, has the answer. Smiley: "We did surveys in 11 counties in Oregon and Washington and found that yes, there were very high populations of lesion nematodes in our annual cropping systems and tillage didn't seem to have any influence at all. The lesion nematode populations were a function of the cropping frequency rather than the tillage intensity." And Smiley says they now have conclusive proof that lesion nematodes cause economic damage in most locations where annual spring cereals are being produced. Smiley: "In our demonstration plots near Pendleton, as well as out at Morrow and in Union County, we have had losses as much as 74%. Now obviously we have also had losses as low as zero percent so we have the full range. But 3/4 of a yield potential is very damaging indeed in some of our cropping systems." Ironically, the nematode was not a problem at the Ralston Project in eastern Washington. Smiley believes developing wheat varieties with resistance to the lesion nematode will be the best control strategy and that will be the focus of further research. I'm Bob Hoff and that's the Northwest Farm and Ranch Report on the Northwest Ag Information Network.