Between 20% to 40% of global crop production is lost to pests annually. Each year, plant diseases cost the global economy around $220 billion, and invasive insects around $70 billion, according to the Food and Agriculture Organization of the United Nations. Weeds are another significant biotic constraint on global food production.
With support from USDA’s National Institute of Food and Agriculture, Land-grant University researchers are addressing high-priority issues related to pests including insects, nematodes, pathogens and weeds, and their management using Integrated Pest Management (IPM) approaches at the state, regional and national levels.
NIFA’s Crop Protection and Pest Management (CPPM) program supports projects that will increase food security and respond effectively to other major societal challenges with comprehensive IPM approaches that are economically viable, ecologically prudent and safe for human health. The program also addresses pest management challenges with new and emerging technologies.
One of the three program areas of CPPM is the Applied Research and Development Program Area (ARDP). This program area funds projects for the development of new IPM tactics, technologies, practices and strategies through research projects. ARDP also funds IPM adoption through research-led projects and IPM implementation through Extension-led projects. Learn more about some of the advances that have been made with funding from this grant program, which is soliciting its next round of grant applications. The application deadline is February 13.
Managing an Emerging Invasive Aphid Pest of Small Grains in North America
Aphids and the viruses they transmit damage many food crops, including wheat. Growers, crop advisors and IPM specialists need vigilance as well as knowledge of aphid species and their injury potential to manage them properly. However, there is limited information regarding the newly invasive cereal grass aphid, M. festucae cerealium, and its potential for causing crop losses.
Furthermore, the knowledge on genetic diversity of the cereal grass aphid is lacking but essential for effective pest management, such as developing economic thresholds, assessing insecticide resistance and determining the capacity to transmit pathogens.
In response, researchers at University of Idaho are developing a decision support tool that will simplify decisions about identifying and managing the aphid pest complex in the Pacific Northwest cereals.
“The threat of invasive insect pests affecting major commodities represents a challenge that requires comprehensive approaches to understanding the biology of these pests, the vulnerability of cropping systems and science-based practices for managing them,” said University of Idaho project director Dr. Sanford Eigenbrode. “NIFA funding has supported valuable research on a newly invasive aphid’s biology, ecology, damage potential, virus transmissibility and potential distribution in the United States.”
Wheat, the prime host of the cereal grass aphid in the Pacific Northwest, is a major commodity in the nation. In Idaho, Washington, Oregon and Montana where the cereal grass aphid is invasive, wheat is planted annually on almost a million acres of land with an annual farm gate value of $2.4 billion in 2021, according to USDA’s National Agricultural Statistical Service.
“Pest management inputs are relatively small compared to other inputs for these systems, but margins are also small such that reductions in yield can have severe consequences. For example, in moderate to high infested years, even if this pest damages only about 5% of wheat in these four states, the estimated economic loss will be about $120 million for growers. Hence, the information collected by this project on this invasive pest will help to aid growers in their timely management, saving a huge amount of money,” Eigenbrode said.
Developing Non-Chemical Harvest Weed Seed Control Strategies in Dryland Crops
Weeds can greatly reduce crop yields, and in the case of feral rye and jointed goatgrass in wheat, they can contaminate the product and result in reduced payments to the farmer at grain delivery because they reduce the quality of the wheat.
While using herbicides to manage weeds is highly useful, some resistance has evolved to some of the herbicides. Fortunately, Colorado State University researchers have found that integrating a cultural management practice like chaff lining with herbicides helps reduce the number of weeds exposed to herbicide selection pressure, keeps weed populations low to protect yield, and makes management of weeds during the fallow period more effective.
“This is a management practice that can help improve sustainability, improve soil health by keeping no-till practices sustainable and help reduce input costs for farmers,” said project director Dr. Todd Gaines.
Gaines explained that chaff lining is inexpensive to implement. A metal structure is added to the back of the combine to split out the fine chaff from the straw. This chaff can be placed in two lines directly behind the combine tires, or a single line in the middle of the combine. This thick layer of wheat chaff creates an unfavorable environment for weed seeds to germinate.
“We found in a previous project that the grass weed feral rye has high seed retention at harvest, and the grass weeds downy brome and jointed goatgrass retain some seeds on the plant at harvest,” Gaines said. “Nearly all of the weed seeds still attached to the weed plants at harvest time are processed through the combine and enter this chaff fraction. This allows you to place the weed seeds into a poor environment for their germination next season, instead of nicely spreading them all across the field to give them excellent germination next season.”
The research also showed that the weed seeds don’t die any faster in this chaff layer, but they are less likely to germinate. They also are concentrated in one strip to allow easier precision herbicide spraying during the fallow period. If farmers can concentrate most of their weeds into the chaff lines, they can use precision spraying to reduce fallow herbicide applications by 90% or more, Gaines said.
“Delaying resistance evolution for the few selective herbicide options is extremely valuable, at the individual farm level and at the bigger regional and national levels,” he said. “Feral rye alone, even in low to moderate infestations, can reduce profits by 50% or more. Chaff lining should quickly pay back the small investment needed to modify the chaff distribution on the combine.”