Moth Mayhem

Insects and humans have a lot in common, especially when it comes to contracting viruses. The Basic and Applied Virology Creative Inquiry project mentored by Dr. Matthew Turnbull from the Department of Biological Sciences is investigating nudiviruses, viruses that infect crustaceans and insects. Specifically, they are looking into one kind of nudivirus that can be sexually transmitted in moths.

The purpose of this Creative Inquiry project is not just a thirst for knowledge, but also a preparation for real-world application. This team focuses on the virus in Helicoverpa zea, corn earworm moths, because of the mass destruction this insect causes in agriculture. “In terms of South Carolina, it hits corn, cotton [and] soybean particularly badly. Those three crops are, I think, valued at about a half a billion dollars annually to the state economy,” Turnbull said.

The team plans for their research to be used by agricultural companies to help develop future pest control methods involving sterilizing large quantities of this insect in the field. Sterilization of this insect would involve an infected male or female moth mating with another found in nature. This could transmit the virus to a healthy moth, and since the virus is highly contagious it would spread rapidly. Additionally, infected females could potentially pass the virus on to their eggs. Once a moth is infected and showing symptoms of the virus, they should no longer be able to produce sperm or eggs. Without these key elements for reproduction, corn earworm moths will not be able to reproduce. This Creative Inquiry team is responsible for the background research on the virus, while commercial companies will be in charge of applying the virus outside of the lab. Hopefully, with many of the moths sterilized, the population will decrease and prevent some of the agricultural destruction that the insect causes.

The team has work to do before their research can be applied in pest control. There are still unknowns about the virus’ infection process and replication cycle. To solve the mysteries of the virus, the team is trying to identify its prevalence in nature. To do that, the team collects samples from agricultural fields, brings them back to the lab and extracts DNA from the moths to detect the presence or absence of the virus. Team members, Jolee Olsakovsky, a junior biological sciences major, and Rachel Choe, a junior genetics major, played an integral role in creating the protocols virus detection during the Summer Creative Inquiry and Undergraduate Research program. Overtime, this will show the team different patterns of where the virus is in the field, and whether or not that pattern matches dense populations of moths. This information could be vital to exploiting the virus to control the moth population.

Releasing sterilized moths into the wild could become a common mechanism for pest management. Alternative methods of pest control are essential as pesticides, a common control method, are subject to resistance as moths evolve in response to pesticide exposure. It takes a long time for scientists to develop new pesticides after the moths have built a resistance, so in order to keep up with the process of evolution, sterilizing moths might be a better solution. This alternative control method can also benefit the ecosystem as it would reduce the detrimental impact of pesticides on beneficial insects such as honey bees.

Teams such as this one are helping to pave a way for new pest control methods and reduce the damage done to agricultural fields. Although the corn earworm may look small, its hefty appetite can have devasting effects.