A Maryland agency has approved a $3.03 million financing package to help Beretta USA Corp. establish a gun manufacturing plant on Maryland's Eastern Shore and expand its existing plant in the Prince George's County community of Accokeek.

The Maryland Industrial Development Financing Authority, an agency of the state's Department of Economic and Employment Development, recently agreed on a loan package that included a $1.34 million loan from Maryland National Bank.

State officials said Beretta will use the money to buy a 25,000-square-foot building in Pocomoke City and equipment to produce firearms. The Eastern Shore plant will employ 50 to 80 people.

Some of the money will be used to modernize and expand the Accokeek plant, where about 520 people work, economic development officials said. Beretta makes 9mm pistols and in 1985 won a $70 million Defense Department contract to supply handguns to the U.S. military.

Phillips Publishing Inc. of Potomac acquired Rotor & Wing International magazine from PJS Publications Inc. of Peoria, Ill. for an undisclosed price. The magazine for helicopter industry professionals has a subscriber base of 38,500 in 172 countries, and will move its operations to Potomac.

The acquisition of Rotor & Wings is the largest in the history of Phillips Publishing, which also publishes three other magazines and more than 30 business newsletters. The company had revenue of $44 million last year.

Institutional Communications Co. (ICC) of McLean announced plans to invest about $5 million in the expansion of its fiber-optic network. The company will install fiber throughout the area to protect against loss of service from fire of power failures.

Plantronics Data Communications Group, which consists of Frederick Electronics Corp. and Plantronics Futurecomms Inc., moved to offices on Interstate 270 in Frederick, Md. The company joins almost 100 other high-technology, scientific, computer and telecommunications firms along the 40-mile stretch of the interstate highway called the I-270 High-Tech Corridor.

General Sciences Corp. of Laurel was awarded a contract by the Mexican National Water Commission to provide its Metpro weather satellite ground station to Mexico's National Meteorological Service. The contract is valued at $565,725.

Universal Meetings and Incentives and Discovery Incentives and Meetings, both of Alexandria, merged to form UMI/Discovery Meetings and Incentives. The new company, based in Alexandria, has 20 employees in the D.C. area and six in Atlanta, and it expects to have about $10 million in revenue this year.

Linton, Shafer & Co., a Silver Spring-based public accounting firm, acquired Hoye, Graves, Bailey & Associates of Bethesda for an undisclosed price. Linton Shafer now has offices in Silver Spring, Frederick and Annapolis.

Biospherics Inc. of Beltsville entered an agreement with the U.S. Department of Agriculture to test a pesticide developed by the company that may be safe for human exposure. The Department of Agriculture will test the product for effectiveness in controlling house flies and lesser mealworms in the poultry industry, although the pesticide may also have home applications, the company said.

University Research Corp. of Bethesda, in cooperation with Berlitz International, began offering an intercultural orientation program and other services to people involved in Japanese-American business activities.Announcements of news and developments affecting Washington area companies should be sent to Regional Report, Business News Department, The Washington Post, 1150 15th St. NW, Washington, D.C. 20071.