|Brown, Charles - Chuck|
Submitted to: Proceedings Washington State Potato Conference
Publication Type: Proceedings
Publication Acceptance Date: 5/1/2007
Publication Date: N/A
Technical Abstract: The Columbia root-knot nematode CRKN (Meloidogyne chitwoodi) is a serious pest of potato in the Pacific Northwest. In the warmer zones, with longer growing seasons, this nematode builds up to high populations and damages the potato tubers by invading and causing discoloration and galling. It is presently controlled by fumigation. About 20 million dollars is spent each year to prevent 40 million dollars of loss. Corky ringspot disease is caused by the transmission of tobacco rattle virus into potato tubers by the stubby root nematode (Paratrichodorus allius). Damage appears most often as dark brown arcs or blotches in the flesh . P. allius is controlled by fumigation by a second product. Together the two fumigations may cost as much as 350 dollars per acre, an expense that may jeopardize the profitability of the crop. Research at USDA/ARS, and at Oregon State University has identified clones with resistance to both nematodes. Clones with resistance to tuber penetration by CRKN have been evaluated and been found to resist a broad spectrum of races and pathotypes. Resistance to corky ringspot has been assessed at multiple locations and found to be stable and durable. Furthermore, we have found that resistance consists of resistance to infection by tobacco rattle virus (TRV). Resistant materials do not harbor the virus in a non-symptomatic state, but rather are free of the virus as tested with a very sensitive assay method. A commercially viable potato variety with resistance to both nematode caused problems could save a potato grower as much as 15 % of the cost of production.