Colorado State Researcher Uses Natural Chemicals To Battle Major Corn Pest

July 25, 1997

FORT COLLINS--Louis Bjostad has whipped up a recipe of death for the Colorado corn industry's No. 1 pest using an inexpensive food processor and ingredients available at most grocery stores.

Bjostad, entomology professor at Colorado State, is testing several non-toxic materials that target Western corn rootworm, a pest that causes $1 billion in crop losses in the United States each year.

After tests in the laboratory and field over the past six months, Bjostad is confident his materials can tackle rootworm just as effectively as insecticides, which are more toxic and expensive.

Bjostad, who has studied the pesky bugs for more than a decade, recently made a breakthrough that showed why rootworm larvae only eat corn plant roots. The professor, with colleagues Elisa Bernklau and Erich Fromm, discovered that carbon dioxide given off by corn roots is responsible for luring larvae to their meal.

To steer rootworms off course, Bjostad and his team of researchers made non-toxic granules and pellets that also release carbon dioxide. The experimental treatments, placed near the corn seed at planting time, mix the signal that larvae rely on to find their only source of food.

"These larvae must find the corn roots within 24 hours after hatching or they die," Bjostad said. "We are essentially sending them away from the plant so by the time they realize their mistake we've dealt a lethal blow."

Main ingredients in Bjostad's treatments include baker's yeast and a nutrient mixture, or sodium bicarbonate (the main ingredient in baking soda), citric and other acids, combinations of which produce carbon dioxide naturally.

In addition, the professor is on the verge of identifying key chemicals responsible for stimulating rootworm larvae to feed on corn roots. Once identified, Bjostad hopes to add these chemicals to his formulas so larvae are not only attracted to the pellets but also are tricked into feeding on the pellet itself. The idea is to keep larvae away from corn roots as long as possible so the plant has time to mature. Corn plants with established root systems are less vulnerable to larvae.

Bjostad has taken his research--already being eyed by major chemical manufacturers for future development into biological products--several steps further. The professor's studies also unexpectedly found that corn roots produce small amounts of natural chemicals that, when produced in large amounts, repel larvae. Because these repellants aren't in high enough doses in commercial varieties of corn to thwart rootworm, Bjostad is studying ways to isolate the natural repellants and manufacture them in large amounts. These concentrated, natural repellents also would be formulated into granules or pellets and applied near the corn seed at planting time.

While biological insecticides are more ideal than toxic chemicals available, Bjostad says the best alternative would be to genetically engineer corn plants that produced higher concentrations of these natural repellents so no man-made chemicals would have to be used.

The next step, Bjostad says, is to refine these natural insecticides so they do the best job possible for the least cost to the farmer. Bjostad plans to conduct two more years of field tests before deciding which compounds should be developed further.

"The health and public safety issue is really driving this research," Bjostad said. "The whole idea is to develop a biological control that isn't toxic, costs less and is safer for workers to handle."

Colorado State University

Related Insecticides Articles from Brightsurf:

Two pesticides approved for use in US harmful to bees
A previously banned insecticide, which was approved for agricultural use last year in the United States, is harmful for bees and other beneficial insects that are crucial for agriculture, and a second pesticide in widespread use also harms these insects.

Insect Armageddon: low doses of the insecticide, Imidacloprid, cause blindness in insects
Joint research provides important evidence on the role of insecticides on the longevity of insect population.

Researchers warn of food-web threats from common insecticides
In an opinion in the journal Proceedings of the National Academy of Sciences, researchers from North Carolina State University and Pennsylvania State University argued for curbing the use of neonicotinoid insecticides.

Alarming long-term effects of insecticides weaken ant colonies
This week, scientists of the Institute of Bee Health of the University of Bern have published an article in the peer-reviewed journal Communications Biology, which shows how even low doses of neonicotinoid insecticides, as they may realistically occur in contaminated soils, adversely affect the development of black garden ants (Lasius niger).

Treatments tested for invasive pest on allium crops
A Cornell University-led team of researchers field-tested 14 active ingredients in insecticides, applied in a variety of methods, to understand the best treatment options against the Allium leafminer, a growing threat to onions, garlic and leeks.

Insecticides are becoming more toxic to honey bees
Researchers discover that neonicotinoid seed treatments are driving a dramatic increase in insecticide toxicity in U.S. agricultural landscapes, despite evidence that these treatments have little to no benefit in many crops.

Time for a closer look at Pyrethroid insecticides
Columbia professors offer their perspective on a recent study on Pyrethroid, among the most widely used insecticides for public health control of vector-borne illnesses, including West Nile virus.

Scientist identify new marker for insecticide resistance in malaria mosquitoes
Researchers at LSTM have genetically modified malaria carrying mosquitoes in order to demonstrate the role of particular genes in conferring insecticide resistance.

The use of certain neonicotinoids could benefit bumblebees, new study finds
Not all neonicotinoid insecticides have negative effects on bees, according to researchers at Lund University and the Swedish University of Agricultural Sciences.

Efficient synthesis of ginkgo compound could lead to new drugs, 'green' insecticides
Chemists at Scripps Research have invented an efficient method for making a synthetic version of the plant compound bilobalide, which is naturally produced by gingko trees.

Read More: Insecticides News and Insecticides Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to