Solar traps and pitfall traps help capture pest insects before they can damage crops, or the traps can be used to monitor populations of insects pests as part of an Integrated Pest Management program.
Dr. Gadi V.P. Reddy and Dr. Anamika Sharma, entomologists/ecologists at Montana State University's Western Triangle Agricultural Research Center, have been studying traps and the use of pheromones to attract insects into those traps.
Solar traps were sent to Anamika from a Canadian scientist, Dr. Christine Noronha from Agriculture and Agri-Food Canada.
Anamika added pheromones to the solar traps to attract the right kind of mating partner of click beetles.
Farmers may be more familiar with the name wirewoms than click beetles, but wireworms are actually the larvae of click beetles.
“Wireworms are very damaging to wheat and barley crops,” Anamika said.
Solar traps are used to attract click beetles at night.
“The traps use a light to attract the beetles, which fly at night to a shorter distance,” she said.
During the day, traps are recharged, which is why they are called solar traps.
“We recheck the traps every seven days, to monitor and find out how many click beetles are in the area,” Anamika said.
While click beetles do not cause any damage to crops like wireworms do, trapping the beetles keeps reproduction from occurring.
In that way, there are no wireworms.
Since there are so many species of click beetles, Anamika and Gadi aren’t sure if the pheromone is attracting the particular species of click beetle they have in Montana.
“Pheromone compounds are species specific,” Gadi said. “No one has identified the pheromone yet for Montana's species of click beetles.”
Gadi contacted Europe and Hungary and obtained lures for different species of click beetles but so far, they have not captured many adults.
If Gadi and Anamika discover it, it would be ground-breaking research - and very helpful to farmers.
Pitfall traps work well for Army worms and cutworms, especially for larvae, on the ground.
“A hole is dug and a small glass with pheromone is placed to the level of the ground for cutworm larvae that do not fly,” Anamika said. “The larvae crawl to the attractant and fall into it.”
Throughout the growing season, the number of cutworms in the field can be counted.
The two also found that a lower amount of pheromone worked better than a large amount for wheat head armyworm.
Anamika concluded that pheromone traps could be used in many ways to attract and monitor several kinds of insects that can damage crops.
Some of the insects are very attracted to pheromones and others are attracted to color
“We can trap insects with pheromone traps for both flying and crawling insects,” she said. “Sometimes we can use the pheromone traps separately or combine them for more efficiency with other methods such as color traps, sticky traps, and plant based semiochemicals, which can function within different species.”
Gadi said in future, pheromones can be used with insecticides to attract and kill the major insect pests in the Northern Plains region.