1In 2-quart saucepan, heat water, wheat berries and 1/2 teaspoon salt to a rolling boil over high heat. Reduce heat to low; cover and simmer 1 hour 15 minutes to 1 hour 30 minutes or until tender. Drain; rinse with cold water to cool. Drain well.
2Meanwhile, heat oven to 450°F. In ungreased 15x10x1-inch pan, evenly spread corn. Drizzle with 1 tablespoon oil; sprinkle with 1/2 teaspoon salt. Bake 15 minutes to roast corn. Set aside.
3In large bowl, stir together wheat berries, corn, spinach, tomatoes and onion.
4In 1-cup measuring cup, mix dressing ingredients with wire whisk until well blended. Stir into salad. Let stand 15 minutes before serving to blend flavors.