Americans consume about 130 pounds of fresh and processed potatoes per capita annually, and in 2008 U.S. farmers harvested some 41.3 billion pounds of spuds on more than one million acres. So making even small changes in how potatoes are grown could yield big benefits for the environment.
Scientists at the Agricultural Research Service (ARS), the principal intramural scientific research agency of the U.S. Department of Agriculture, are making potato production as sustainable and environmentally friendly as possible. So far, plants in the mustard (Brassica) family, which have natural pest suppression properties, have been key partners in this effort.
At the ARS New England Plant, Soil and Water Laboratory in Orono, Maine, scientists have conducted long-term research with canola and other Brassica crops in rotation with potatoes since 1997. Theyve found that with the right crop rotation, potato farmers can naturally suppress diseases, enhance soil nutrient content, boost crop productivity, and lower the use of fertilizers, all of which lower the risks of economic losses.
Using rotation crops has reduced some soil-borne diseases from 20 to 50 percent. Canola crops are particularly promising because they produce potent sulfur compounds that can knock down powdery scab and Rhizoctonia fungus.
On the other side of the country, scientists at the ARS Vegetable and Forage Crops Production Research Unit in Prosser, Wash., have found that one to two tons of crushed mustard seed meal applied per acre without herbicides significantly reduced early weeds in potato fields. Mustard seed meal is left over after vegetable oil has been extracted.
Potato producers in the Pacific Northwest already use white and brown mustards as cover crops in rotation with potatoes to reduce wind erosion and help control plant pathogens. The Prosser researchers also determined that mustard cover crops can contribute more than 30 pounds of nitrogen to each acre of crop soil, which could save farmers $14 to $30 per acre, depending on the cost of nitrogen fertilizers.
ARS research to reduce the need for pesticides used in potato production is part of a larger mission to support and enhance more sustainable agricultural production of food, feed, fiber and fuel throughout the United States.