Boston University trustees voted yesterday to give undergraduates control of a board which will elect B.U. News editors for the first semester next fall.

While the plan adds three students to the four already on the nine-member News publishing board -- giving them 7-6 voting control on the new board -- it also means that the eight editors serve for a semester instead of the present one year term.

"I think the one-semester election procedure represents a danger," Steven D'Arazien, Managing editor of the News, said last night. "It puts political pressure on editors who know they will come up for examination in the middle of the year."

D'Arazien said the one-semester proposal was not a recommendation of B.U. president Harold C. Case's 11-man committee which has been studying the News. "The trustees did it in reaction to Case's dissatisfaction with this year's staff," D'Arazien said.

News editor Ray Mungo, who Thursday threatened a university-wide sit-in if Case did not allow the paper to elect new editors by next Tuesday, is out of town writing an honors English paper and was unavailable for comment.