"We discovered indoxacarb as a new crop-protection insecticide that's environmentally friendly and is safe for farmers to use," said McCann, a chemist who specializes in organic synthesis at DuPont's Stine-Haskell Research Center in Newark, Del.
"It has a mode of action that's different from any others being used now," he continued. "That means it can be used at lower application rates than current products because insects aren't resistant to it -- and it breaks down rapidly in the environment."
Indoxacarb blocks a nerve membrane channel that conducts sodium atoms, a critical step in communication between nerves. With sodium channels clogged, the nerves can't signal -- and thus at even low levels of insecticide, the jaws of insects can't chew on crops.
The insecticide, marketed as Steward® and Avaunt®, is effective for a variety of crops, including tomatoes, soybeans, vines and tree fruit. It has made particular impact in the countries of West Africa, where farmers are heavily dependent on growing cotton. The Helicoverpa armigera caterpillar, or cotton bollworm, is a regular plague that eats the young leaves and buds of cotton plants.
McCann's role as team leader in indoxacarb's development was to discover its molecular architecture, the oxadiazines, which were derived from other sodium-channel blockers but break down more quickly in the environment.
Among what McCann called "a host of contributors," Lahm, also an organic chemist, was the team leader who instigated the search for a sodium-channel blocker and discovered several early leads; Wing, a biochemist and co-discoverer of indoxacarb, uncovered and defined how these types of compounds target destructive insects; Harrision, formerly an organic chemist at Dupont Crop Protection, invented earlier subclasses of indoxacarb's molecular structure; and Shapiro, another organic chemist, discovered and developed some of the critical methods for commercial synthesis.
McCann's received his undergraduate and Ph.D. degrees from the University of California, Irvine, in 1979 and 1987. He is a member of the ACS division of organic chemistry.
Lahm received his undergraduate degree from the State University of New York, Oswego, in 1976 and his Ph.D. from Indiana University in 1980.
Wing received his undergraduate degree from the University of California, Los Angeles, in 1976 and his Ph.D. from the University of California, Riverside, in 1981. He is a member of the ACS division of agrochemicals.
Harrison, a member of the ACS organic chemistry division, received two undergraduate degrees from the University of Central Florida in 1979 and 1980 and his Ph.D. from the Georgia Institute of Technology in 1984.
Shapiro received his undergraduate degree from Rice University in 1972 and his Ph.D. from the Massachusetts Institute of Technology in 1978.