Preheat oven to 350°. Grease and flour a 9 by 5 loaf pan; set aside. In large bowl, blend flour, baking powder, and salt; set aside. In medium bowl, beat 2 eggs well, then add canola oil and sugar, and blend well. Then add the buttermilk, lemon juice, and lemon zest and blend everything well. Fold in zucchini and stir until evenly distributed in mixture. Add this mixture to the dry ingredients in the large bowl and blend everything together, but don’t overmix. Pour batter into prepared loaf pan and bake at 350° for 45 minutes, or until toothpick inserted in center comes out clean. Cool in pan 10 minutes, then remove to a wire rack and cool completely. While loaf is cooling, you can make the glaze.In small bowl, mix powdered sugar and lemon juice until well blended. Spoon glaze over cooled loaf. Let glaze set, then serve.