University of California, Davis scientists are redirecting their research after a professor's son discovered that a major agricultural pest prefers pistachios over other nuts.

The sixth-grader's experiment showed that female navel orangeworms preferred to lay their eggs in pistachios rather than in almonds or walnuts, and researchers now are trying to use the information to better control the pests, states a California Farm Bureau e-mail news bulletin.

Gabriel Leal, 11 and a student at Willet Elementary School in Davis, thinks pistachios taste better and theorized that navel orangeworms share a similar preference.

So in September he text messaged his father, Walter Leal, a chemical ecologist and professor of entomology at UC Davis, who was in his native Brazil at an entomology conference.

Gabriel told his dad he wanted to do a science project centering on the hypothesis that the navel orangeworm would lay more eggs in pistachios than in almonds or walnuts, a UC Davis news release states.

The hypothesis runs counter to past research, including a report recently published in the California Agriculture journal, which indicates the pest prefers almonds.

Gabriel conducted the research in his father's UC Davis lab under the voluntary supervision of Zain Syed, a chemical ecologist.

Gabriel placed mated and gravid, or egg-filled, females in a cage. He used four commercially available navel orangeworm traps and filled one with 50 grams of shelled pistachios, one with 50 grams of almonds, one with 50 grams of walnuts and left the fourth empty to serve as the control, Syed stated in the release.

The eggs laid in the traps were counted for two consecutive nights.

Enough eggs were laid in the pistachios to demonstrate that female navel orangeworms prefer pistachios over the other nuts.

"The results shocked us," Syed stated in the release.

Walter Leal reported the findings at the state almond industry conference last month in Modesto.

"We are very excited with our little scientist's discovery," Walter Leal stated in the news release.

Researchers and growers typically use traps baited with a mix of almond meal and almond oil to attract the pests in the field. But during the hull split, the chemical from the real crop competes with the synthetic material in the traps, Leal said.

If pistachio-derived sources are used in the almond fields, it could eliminate the problem throughout the flight season, he said.

The navel orangeworm, a gray-colored moth with black markings, is considered the key insect pest of almonds and pistachios in the state because the larvae feed directly on nut meats, making them unsuitable for sale, the release states.

The pest attacks tree crops planted on more than 1 million acres throughout the state.

"The economic impact of (navel orangeworms) damage varies from year to year, but it can easily reach $10 to $15 million for our company and much higher statewide," Brad Higbee, research entomologist for Paramount Farming Co. in Bakersfield, stated in the release.

Walter Leal, who led groundbreaking research that determined mosquitoes can smell DEET and avoid it because it smells bad, said science should never underestimate an idea.

"That's why the academic environment is so enriching," he stated in the release. "Students come with new ideas, but I never imagined we would benefit so much from a science project for elementary school."

Call The Bee's Niesha Lofing, (916) 321-1270.