Wheat was a type of food-grain with varieties found throughout the Milky Way Galaxy.
In 2374, instability in the Bajoran wormhole caused by the Reckoning led to widespread flooding in Rakantha, destroying two-thirds of the wheat harvest. (DS9: "The Reckoning")
The famous orbital skydiving deleted scene from Star Trek Generations had James T. Kirk land in a wheat field.
Types of wheat
Furthermore, Quadrotriticale was initially described as wheat by James T. Kirk, only for him to be corrected that it was not wheat but a high-yield grain that was a hybrid of wheat and rye.