ECONOMY T-bill yields rose. The Treasury sold $9.0 billion in 13-week bills at an average discount of 7.81 percent, up from 7.73 percent last week, and $9.0 billion in 26-week bills at an average discount of 7.75 percent, up from 7.60 percent last week. The investment rate was 8.08 percent for the three-month bills and 8.18 percent for the six-month bills.

MARKETS The Philadelphia Stock Exchange said it will extend its trading day in foreign currency options by 6 1/2 hours to coincide with afternoon trading in the Far East and Pacific Rim countries beginning Sept. 16. The new hours will run from 7 p.m. overnight through 3:30 p.m.

COMPANIES Johnson Wax, maker of OFF! insect repellent, filed a trademark infringement lawsuit against EcoSafe, which makes SKEETER OFF, an herbal lotion mixed with citronella. EcoSafe President Wayne Ellison said his product is available only in health food stores and has sold only 3,000 bottles since the product was introduced last fall. Philip Morris, the maker of Marlboro cigarettes as well as other brands, said it plans a five-year, $500,000 advertising campaign to warn candy, toy and apparel manufacturers against using its trademarks on products aimed at children. Texas Instruments filed a patent infringement lawsuit and an International Trade Commission complaint against five semiconductor manufacturers over the use of a TI patent process. Delta Air Lines said it has requested federal permission to add three new international routes: Atlanta to Manchester, England; Atlanta to Madrid and Barcelona; and Orlando, Fla., to Mexico City. Coach Leatherware charged in a lawsuit that specialty retailer Ann Taylor Inc. deliberately copied some of Coach's most popular handbags.

REGULATION The Federal Trade Commission asked for more information about ConAgra's planned acquisition of Beatrice Co. from Kohlberg Kravis Roberts for $1.34 billion. ConAgra and Beatrice officials said there appears to be nothing unusual about the request.

ACQUISITIONS Baltimore Spice was purchased by German spicemaker Fuchs Gewuerze GmbH from Hanson Industries for $23.9 million. Hanson will retain the retail Old Bay Seasonings business, which was not included in the sale. Baltimore Spice is headquartered in Garrison, Md., and has plants in Maryland, North Dakota and Nevada.

INTERNATIONAL The Soviet Union, facing a lack of fuel for domestic use, will cut its oil exports by 140,000 barrels a day, Premier Nikolai I. Ryzhkov said. The European Community unemployment rate has remained steady at 8.6 percent for the first five months of the year. Unemployment ranged from 1.7 percent in Luxembourg to 16.6 percent in Ireland, the EC reported. East European and Soviet economies continued to weaken in the 1990 first quarter, the U.N. Economic Commission for Europe reported. The commission said collective industrial production in the East Europe was down 13.4 percent compared with the 1989 period. Exports were 14.2 percent lower. In the Soviet Union, there were declines of 2 percent in net material product, 1.2 percent in industrial output, 5.4 percent in gross investment and 7 percent in exports.

CONTRACTS Harsco received a $260 million, four-year contract to supply howitzers to the Republic of Korea. GTE Spacenet of McLean has signed a $4 million, five-year contract with Group W Satellite Communications to distribute television programming by Home Team Sports, a regional sports network based in Washington. Advanced Technology of Reston received a $2.5 million Department of Transportation contract to develop a prototype computer system that will allow officials to track defense and commercial transportation networks worldwide.

EARNINGS Nike reported an 84 percent rise in its fourth-quarter profit over the same period last year.

PEOPLE Donald Trump said Galeries Lafayette, the giant French retailer, will open a branch store in Trump Tower, helping to solidify the value of his 68-story skyscraper on Fifth Avenue.

ODD LOTS A majority of consumers, 96 percent, said environmental factors play a ''very important'' role in their purchase decisions, according to a nationwide survey commissioned by Warwick Baker & Fiore, a New York advertising agency, and Adweek's Marketing Week publication. But the survey also reported that only 5 percent of consumers were able to name a company or brand as environmentally ''friendly.''