Plant stomata, the tiny openings on the underside of the leaf, take in CO2, but water evaporates from the plant at a higher rate when stomata are open. With higher CO2 concentrations in their air, plant stomata can absorb CO2 faster, and stay open for not as long, resulting in less water loss. Especially the C3 photosynthesis plants, including wheat, rice, rye, oats, peanuts, soybean, and most trees, including fruit trees.
Some plants evolved a different method of photosynthesis, known as C4, including corn (maize), sugarcane and sorghum. These plants benefit less from a higher level of CO2, but studies are showing they do benefit. The usual faster and bigger growth, like C3 plants, and requiring less water for that growth, like C3 plants.