Heat oven to 350°F. Spray 13x9-inch (3-quart) glass baking dish with cooking spray.
Cook pasta shells as directed on box. Rinse with cool water; drain well.
In 10-inch nonstick skillet, cook turkey, onion and garlic salt over medium heat about 5 minutes, stirring frequently, until turkey is no longer pink. Remove from heat. Stir in yogurt, broccoli, 1/2 cup of the cheese and the Italian seasoning.
Spread 1/2 cup pasta sauce in baking dish. Spoon turkey mixture into shells; arrange in baking dish. Spoon remaining pasta sauce over shells. Cover with foil. Bake about 25 minutes or until hot and bubbly. Sprinkle with remaining 1 cup cheese. Bake about 5 minutes longer or until cheese is melted.