On the outside, a row of fresh apples may look perfectly normal.

Inside, though, something could be lurking.

People might not know until they bite into the fruit and hit a rotten texture. They peer into the core and a little vermiform creature looks back. They are face to face with one of the biggest problems in orchard farming: apple maggots.

Researchers, including adjunct associate professor Stephanie Bloem and adjunct professors in entomology Allen Cohen, are working to alleviate the effects.

Apple maggots, sometimes called apple worms, are the larvae of the Codling moth (Cydia pomonella), and they feed on pome fruits like apples or pears. These larvae are not at all related to worms or maggots — they are actually caterpillars.

Many orchard farmers insist on spraying with insecticides, but Codling moths have developed resistance to chemical treatments, according to the entomology Web site.

The most successful tactic used in controlling these pests is a sterile release technique, in which the moths are raised in mass numbers and exposed to radiation, according to the researchers.

The gamma rays of the radiation treatment effectively neuter them. After the moths are sterilized, they are released as adults to compete as mates with wild moths. The more times a wild moth mates with a sterile moth, the fewer times wild moths actually reproduce.

According to Bloem, who is also an insect rearing specialist with the United States Department of Agriculture, a successful rearing facility can produce upward of 2.2 million sterile moths a day.

This is no trivial feat, as the larvae of these moths are cannibalistic. In the wild, there is only one larvae per apple. If two larvae happen to infest an apple, one will eat the other. This freedom of space is not allowed in a mass rearing facility.

The rearing facility employs a secret ingredient: sawdust. Sawdust has no nutritional value for the moth larvae, but it is large enough to compartmentalize the diet and prevents the caterpillars from interacting in the trays and eating each other.

The sterile release program is a $900 million a year industry. Cohen said practices like this are underutilized.

“[Bloem’s] facility is only operational 22 weeks a year,” he said.

It could be operational year-round because the codling moth produces two generations a year, thereby quadrupling output, as well as income.