AUBURN ® — Joseph A ‘Blackie’ Levesque, a paroled convict, went on trial in Superior Court today charged with murder in the knifing of Mrs. Marguerite Couture at Lewiston last Dec. 12. The 37-year-old Levesque hob bled into the courtroom on crutches. He still suffers from a leg, infection resulting from a fall shortly before the 36-year-old housewife was slain in her bed room. After a 14-hour pre-trial con ference on questions to be asked prospective jurors, counsel for the state and defense started trying to pick a jury from 16 reg ular and 50 extra talesmen. Levesque, who was paroled last September from a prison sen tence for manslaughter, alleged ly killed Mrs. Couture when she resisted his advances. He had gone to her home with her husband, whom he had met in a beer parlor. Levesque told police that Mrs. Couture and he had been childhood sweethearts.