preheat oven to 350. grease 2 9x5 inch loaf pans and coat sides with 1/4 cup sugar, set aside.
in large bowl, combine the flour, baking powder, baking soda and salt. add in the blueberries, toss to coat and set aside.
in a medium bowl, beat eggs with sugar, until light and fluffy. add in the canola oil and blend well. add the milk, lemon juice and lemon zest and blend until well combined. stir in zucchini, until evenly distributed in mixture.
add this mixture to the dry ingredients and blend everything together, until just combined.
pour batter into prepared loaf pans and bake at 350 for 45-60 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 a small bowl, mix the powdered sugar, lemon juice and zest until well blended. spoon glaze over cooled loaf. let glaze set, then serve.