Food grain and Wild rice

Food grain noun - Foodstuff prepared from the starchy grains of cereal grasses.

Wild rice and food grain are semantically related. In some cases you can replace phrase "Wild rice" with "Food grain", this phrases are similar.

Wild rice noun - Grains of aquatic grass of North America.

Food grain and wild rice are semantically related. You can use "Food grain" instead a noun phrase "Wild rice".