You can use boneless, skinless chicken breast halves instead of turkey.
Heat a large nonstick skillet over medium-high heat. Coat pan with cooking spray. Sprinkle turkey with 1/4 teaspoon salt and 1/8 teaspoon pepper. Add turkey to pan; sauté 6 minutes.
Place broth in a medium saucepan; bring to a boil. Add corn to pan; cook 3 minutes. Add couscous to pan. Remove from heat; cover and let stand 5 minutes. Fluff with a fork.
Combine remaining 1/4 teaspoon salt, remaining 1/8 teaspoon pepper, tomato, and remaining ingredients in a large bowl. Add turkey and couscous mixture to bowl, and toss well.