USDA research finds climate change may improve production of potatoes
By Wes Nelson
Farm Service Agency
WILLMAR — Despite all of the attention being given to the negative impacts that climate change may have on agriculture and agricultural production, recent research conducted by the U.S. Department of Agriculture indicates that when it comes to potatoes, climate change may actually enhance production potential.
David Fleisher, an agricultural engineer with USDA’s Agricultural Research Service, conducted studies to measure how potato plants would respond to elevated atmospheric carbon dioxide levels, and the increasingly erratic rainfall patterns expected to result from climate change.
Working with a team of colleagues, Fleisher conducted two outdoor chamber studies to evaluate the effects of short-term drought cycles at current and elevated carbon dioxide levels. The chambers provided precise control over carbon dioxide levels, air temperature, irrigation and humidity. They also contained sensors that monitored air, soil and canopy temperatures, relative humidity, and solar radiation above and below the canopy.
In the first study, the quantity of solar radiation was about twice as much as in the second. Having two different study periods allowed the scientists to evaluate how variations in solar radiation during the drought periods affected plant response.
The researchers observed significant differences in the potato plant’s response to increased solar radiation, which in turn affected plant water-use efficiency and dry matter production. With all other growth factors being equal, plants receiving increased levels of solar radiation had a 30 percent to 200 percent increase in total dry matter, depending on carbon dioxide levels and water availability.
The team also noted that drought stress before tuber formation probably enhanced the future delivery of water and plant nutrients to tubers instead of to stems or leaves — and that this response increased under elevated carbon dioxide levels.
Averaged across all drought simulations, tuber yield from plants growing under elevated carbon dioxide levels was as much as 60 percent greater than tuber yield from plants growing under current carbon dioxide levels.
To view the entire findings of this research, visit www.ars.usda.gov.
U of M develops second diagnostic test for PED virus
The University of Minnesota’s College of Veterinary Medicine has developed a second diagnostic test to help stem the spread of a deadly virus currently threatening North American swine populations called porcupine epidemic diarrhea, commonly referred to as PED.
The test is the first announced PED virus swine herd surveillance test in the United States, and brings the diagnostic testing up to swine industry disease monitoring standards.
This past summer, the College of Veterinary Medicine developed a diagnostic test that detected the presence of the virus. The recently announced second test not only detects evidence of the virus, but is also a very precise tool in detecting a history of exposure to the virus.
If one pig has been exposed to the virus, all other pigs around it are at risk. The new test will allow the swine industry to identify which pigs have been exposed to PED and act accordingly, even if animals have not shown symptoms of the disease.
Characterized by acute diarrhea and vomiting in pigs, outbreaks can wipe out an average of 50 percent of young swine at newly infected farms. The virus has now been confirmed by USDA in 23 states and Canada, and continues to spread quickly.
Latest figures put pig mortality from PED at an estimated 3 million pigs nationwide. Unfortunately, there is no known effective vaccine or treatment for the virus at this time.
Minnesota to increase efforts to support pollinator populations
Honey bee pollination of U.S. crops is valued at $15 billion to $18 billion, while pollination by native bees is valued at $3 billion. Those numbers alone speak loudly of the important role that insect pollinators play in agriculture and food production.
Following recent developments and concerns regarding the decline in populations of honey bees and other insect pollinators, during its 2013 session, the Minnesota Legislature directed the Minnesota Department of Agriculture to propose ways to create and enhance habitat for bees, flies, wasps, butterflies and other insects.
The legislature also asked the Minnesota Department of Agriculture to collaborate with other state agencies in preparing a report on pollinators, which was recently released.
The report notes that many interacting factors affect pollinator populations. Those factors include pathogens and parasites, pesticides, poor nutrition due to a loss of foraging and nesting habitat, fewer beekeepers, changes in land use, and changes in local weather or climate.
The report also identifies ways to enhance pollinator habitat through a mix of state, federal and nonprofit programs, and how to close research and data gaps regarding pollinator species.
One concern raised was how to provide the habitat needed by honey bees, which can often differ from that required by native bees and other pollinators. But to do so effectively, an inventory of all pollinators is also needed to determine abundance, diversity and the populations at risk.
The Legislature also asked the Minnesota Department of Agriculture to assist in developing a process for reviewing neonicotinoid pesticides registered in the state.
These pesticides, which have home, institutional and agricultural uses, including the control of the emerald ash borer, are implicated as a risk factor in the health of pollinator populations. A review of these pesticides has begun, and in the next few months a draft scoping document will be released for public comment.
The report on pollinators was done in collaboration with the Minnesota Department of Natural Resources, Minnesota Department of Transportation and the Minnesota Pollution Control Agency. Other collaborators included the University of Minnesota, the Board of Soil and Water Resources, and local representatives of USDA’s conservation programs.
Wes Nelson is executive director of the USDA Farm Service Agency in Kandiyohi County.