Tear bread into chunks, and place in a food processor; pulse to make fresh bread crumbs. Transfer crumbs to bowl; set aside. Place salmon in processor, and pulse 5 seconds. Return crumbs to processor; add cilantro, curry, ginger, onion powder, and salt; pulse to blend. Shape mixture into 4 patties. Heat grill.
In bowl, combine ingredients for Cucumber-Yogurt Sauce. Spray patties with vegetable cooking spray. Grill 3 minutes per side, or until cooked through. Serve wrapped in flat bread and topped with Yogurt Sauce.