Houston Astros -- Announced signing of OF Cameron Drew, their No. 1 selection in the regular phase of the major league draft, to a one-year contract. Los Angeles Dodgers -- Signed OF Chris Gwynn, selected in first round in free agent draft, terms not disclosed; will make pro debut Tuesday with team's Vero Beach farm club of Florida State League. OF Al Oliver (pulled hamstring) was reactivated and will be dressed tonight when the club plays Atlanta. Atlanta Braves -- Announced they will recall C Larry Owen from AAA Richmond to fill in for Bruce Benedict (bruised upper torso) and Rick Cerone (strained tendon in right shoulder), who will remain on the roster but unable to play. Oakland A's -- Signed SS Walter Weiss, their first-round choice in draft; the 11th player chosen overall, he had a regular season batting average of .316 for the University of North Carolina this year. FOOTBALL

New Jersey Generals -- RB Herschel Walker was named the U.S. Football League player of the month for May; he rushed for 595 yards in four games. COLLEGES

Navy -- LHP Drew Tanner of Douglas, Ga., and second baseman Bob Dishman of Linthicum were named to the Eastern Intercollegiate Baseball League all-star team. C Ted Wallace of Southington, Conn., was a second-team selection. University of South Florida -- John Wadas, athletic director since 1982, resigned because of lack of funding for athletic programs.