Potatoes

The potato (Solanum tuberosum) is the most important vegetable in the world. Annual production hovers around 700 billion pounds. This is almost twice as much as the total for the number two vegetable, the cassava, and roughly triple production totals for the next three, which are, in descending order, the sweet potato, the tomato, and the watermelon. Four of these five are native American plants unknown in Europe, Asia, or Africa before 1492. The watermelon came to the Americas with the slave trade from Africa.