Green Watermelon
From the Super Mario Wiki
Green Watermelons are watermelons found in Super Mario World 2: Yoshi's Island. If a Yoshi eats it, the dinosaur will be able to shoot seeds. Grinders have many Green Watermelons, some half-eaten, which only let a Yoshi spit out half as many seeds as a full melon. Grinders use the watermelons to spit seeds. The seeds have the same effect on enemies as an egg. Yoshi and a Bandit duel with them in the Mini Battle Watermelon Seed Spitting Contest.
