Host Status of Selected Crops to Meloidogyne chitwoodi.

Various crops were tested in greenhouse and field trials for their potential utility in the rotation sequence in the potato cropping system in Meloidogyne chitwoodi-infested soils of the Klamath Basin in northeastern California and southern Oregon. Two Solarium accessions from the International Potato Center in Peru were potential sources of resistance to M. chitwoodi. Cultivars of barley, oat, rye, wheat, and white lupine were maintenance hosts, supporting the nematode population at its current level without substantial increase or decline. Poor to nonhosts to race 1 of the nematode included cultivars of alfalfa, amaranth, oilseed radish, oilseed rape, and safflower. These crops have potential for inclusion in the cropping system but are subject to various constraints, including frost sensitivity and availability of markets. Sugarbeet, a new crop in the area, is a maintenance or better host of M. chitwoodi. Potato, tomato, and sunflower are excellent hosts.