ARS | Publication request: VOLUNTEER SPUDS: NEW CHEMICALS MAY EASE POTATO ROTATION

Submitted to: Spudman
Publication Type: Trade Journal
Publication Acceptance Date: January 1, 2003
Publication Date: February 1, 2003
Citation: Spudman, Feb. 2003, pp. 40.

Interpretive Summary: Results of volunteer potato control research weed control research in potatoes was presented at the recent potato field days in Othello and in Paterson, WA. Several mild winters have resulted in the worst volunteer potato problem in recent history. Many potatoes that are left in the ground are more than 10 cm deep and are rarely subjected to freezing temperatures. Volunteer potatoes compete with the rotational crops lowering yields and they can harbor nematodes and diseaes of potato, defeating the purpose of crop rotation. Integrated programs that include mechanical control,herbicides, and cultural practices are the most effective in reducing volunteer potato tuber numbers. Several new herbicides offer promiss in controlling volunteer potatoes in corn. New herbicides are also being tested for weed control in potatoes including dimethenamid-P, sulfentrazone, and flumioxazin, all of which should be registered for use in potatoes in the next couple of years. These herbicides will help manage herbicide resistant weed populations and give growers new tools for nightshade and other broadleaf weed control in potatoes.

Technical Abstract: After three mild winters, volunteer potatoes are an increasing problem in Pacific Northwest potato rotations. In dry soil, tubers can supercool to 25 F before freezing. Many tubers that are left in the field are more than 10 cm deep and seldom exposed to freezing temperatures. Carfentrazone and mesotrione herbicides were recently tested for volunteer potato control in corn. Three applications of carfentrazone or a single postemergence application of mesotrione controlled volunteer potatoes well and greatly reduced new tuber production. Three new herbicides, dimethenamid-P, sulfentrazone, and flumioxazin were tested in potatoes and provided excellent hairy nightshade control.