Preheat oven to 350°.
Combine 1 cup sugar, oil, and egg in a medium bowl, and stir with a whisk until smooth. Stir in milk and yogurt. Lightly spoon flour into dry measuring cups, and level with a knife. Combine flour, 1/4 cup coconut, orange rind, baking soda, and 1/2 teaspoon salt in a large bowl, stirring with a whisk. Make a well in the center of flour mixture, and add milk mixture to flour mixture, stirring just until moist.
Spoon batter into a 9 x 5-inch loaf pan coated with cooking spray. Sprinkle with remaining 1 tablespoon coconut. Bake at 350° for 50 minutes or until a wooden pick inserted in center comes out clean. Cool in pan 10 minutes.