MISSISSIPPI STATE -- While some scientific breakthroughs never seem to touch everyday lives, genetic engineering affects many Mississippians on a daily basis.

Two Mississippi State University extension agronomists said bioengineered crops are riding a wave of popularity. In five years, nearly all the corn planted in Mississippi will have bioengineered traits. Because of limited seed supplies, about 5 to 10 percent of the state's soybeans are genetically modified now, but that number is growing quickly.

"Bioengineering speeds up the breeding process by making more rapid improvements," said Dr. Erick Larson, MSU extension corn specialist. "While it might take numerous years to selectively breed for the qualities you want, with bioengineering, you're able to incorporate specific technology into first-rate varieties."

Genetic engineering of these crops concentrates on either killing the crops' pests or making them resistant to herbicides.

Roundup Ready soybeans are gaining popularity in the state for their ability to withstand Roundup herbicide. Bt (Bacillus thuringiensis) corn, being introduced commercially this year, has the ability to kill specific insects that eat the plants.

"With soybeans, the predominant focus is developing herbicide-resistant plants," said Dr. Alan Blaine, MSU extension soybean specialist. "The main objective is to use more effective compounds, lower herbicide use and hopefully reduce cost."

Bioengineering appears to be doing that, he said.

With traditional soybean production, several necessary herbicide applications account for much of the production cost. So far, even with the technology fee added to the cost of transgenic soybeans, effective weed control costs less than it does with conventional varieties, Blaine said.

"If it costs too much money, most farmers are not going to accept this technology since they look for the most cost-effective way to produce crops with the maximum return," he said. "Farmers will grow transgenic crops if they offer a financial edge."

In 1998, a transgenic soybean variety resistant to the Liberty herbicide will be available in addition to Roundup Ready.

Bioengineered corn is new as a commercial crop this year in Mississippi, Larson said. Northrup King is offering Bt corn hybrids resistant to the European and Southwestern corn borer.

Larson said the Environmental Protection Agency recently approved Northrup King to sell corn for 100,000 acres in the South on the condition that the Bt corn acreage must not exceed 5 percent of the corn acreage in a county.

Larson said this restriction was made to avoid possible compatibility problems with Bt cotton. Insecticide resistance of the corn earworm, called the bollworm in cotton, may develop more quickly without acreage limitations.

Mycogen is also offering a Bt corn in Mississippi, but has an even smaller market share than does Northrup King, Larson said. Major seed companies such as Pioneer, DeKalb and AgriPro have Bt varieties, but none that are available in the South.

With only limited hybrids of the Bt corn available to date in the state, it's hard to tell how well the crops will yield in Mississippi. Larson, however, expects Bt hybrids to resist insect damage "extremely well."

Corn borers are difficult to control with insecticides since they cannot be reached once they have bored into the plant. Farmers have only a narrow window in which to act, and must extensively scout the fields to know when to start spraying.

"Bt corn lessens the need for scouting fields for that particular insect while exhibiting more effective control," Larson said.

Because insecticide resistance builds in pests and herbicide resistance in weeds, companies are constantly working to develop new strains of Bt resistance to combat this.

Further research is working to stack Bt resistance for more than one pest or herbicide.