The Threat of Aphids to Agriculture

Agriculture plays a pivotal role in human civilization by enabling us to fulfill demands for nutrition, fiber, and raw materials in our daily lives. However, major disruptions to food production on a global scale occur on a regular basis due to small, yet highly destructive creatures: ravenous pests. Pests, ranging from insects to microorganisms, are invasive species that plague trees and crops. They damage, poison, or simply ruin the food humans eventually consume. They can cause long-lasting forms of harm to the environment and economy and often threaten the health of people who consume the tainted crops. Within the current global marketplace, the volume of international trade inadvertently allows many of these pests to enter different countries, further intensifying the fear of the exponentially increasing number of pests. Many of these pests and blights have severely harmed urban and rural landscapes. Revenue losses are in the billions of dollars, along with millions in cleanup costs. Some scientists estimate that $1 billion dollars are lost annually in the United States due to the economic impacts from the pests. Given the gravity of these agricultural catastrophes, the US Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS) prioritizes keeping these pests and diseases out of the country.

One species of pests, in particular, classified as aphids, presents an acute threat to agriculture. Aphids—small, soft-bodied insects with long, slender mouthparts used to pierce stems, leaves, and other tender plant parts and suck out their fluids—damage many food crops, but, perhaps worse, the viruses they transmit can result in severe damage and sizable crop loss. Large numbers of aphids can damage young plants by hindering their growth, marring the fruit’s appearance, or even causing the death of the plant. Some aphids feed on fruits, which can disfigure the product and reduce its selling price. Unfortunately, aphid-transmitted viruses are hard to control: it takes only a short time for a host plant to become infected. Aphids damage many food crops, but their harmful impact on wheat crops is a special worry, as wheat is a staple ingredient in many everyday foods.

Attempts to achieve effective control of the aphids are ongoing, but a new, highly invasive cereal grass aphid, M. festucae cerealium, is producing considerable fear due to its potential for causing crop losses. In response, researchers at the University of Idaho are developing a decision support tool that facilitates identifying and managing the aphid pest complex in the Pacific Northwest. Wheat is a major commodity in the nation, and in Idaho, Washington, Oregon, and Montana, where cereal grass aphids are rampant, wheat is planted annually on almost a million acres of land, according to the USDA’s National Agricultural Statistical Service. The growing number of aphids and their appetite for wheat presents an immediate and critical threat to food abundance both in this nation and in the world at large.