Major World Crop Belts and Staple Foods

Three cereal grains — wheat, rice, and maize — together supply roughly half of the calories consumed by humanity, and each dominates a distinct climatic and geographic belt. According to the Food and Agriculture Organization's FAOSTAT database, global maize production exceeded 1.1 billion tonnes in the early 2020s, narrowly ahead of wheat, at roughly 780 million tonnes, and rough paddy rice at close to 790 million tonnes. Maize thrives in warm, well-watered temperate summers; wheat tolerates cooler, drier continental climates and can be sown as either a winter or spring crop; rice, by contrast, is overwhelmingly a crop of the monsoon tropics and subtropics, grown in flooded paddies that suppress weeds and stabilize soil nutrients. This threefold division of the world's staple grains into distinct climatic niches is the single most basic fact of global agricultural geography, and it explains why famine, price shocks, or export bans affecting one grain rarely translate directly into shortages of another.