Combine first 6 ingredients in a large bowl; toss well.
Spoon mixture into a 13- x 9- x 2-inch baking dish coated with cooking spray.
Combine 1/2 cup flour, 1/4 cup sugar, and 1/4 cup brown sugar.
Cut in margarine with a pastry blender until mixture resembles coarse meal.
Sprinkle over blueberry mixture.
Bake at 350° for 50 minutes or until golden