Maria Agresta has withdrawn from the San Francisco Opera’s upcoming production of Puccini’s “Turandot” due to illness. The company announced that American soprano Toni Marie Palmertree will sing Liù, replacing Agresta and will now perform in all six September performances. Palmertree scored a triumph last season when she substituted for an ailing colleague on two hours’ notice as Cio-Cio-San in Puccini’s “Madama Butterfly.” {…}