Rice originated in China and is the main food crop in southern China. Wheat was introduced into China before the Yin Dynasty, and it was the main grain crop in northern China. Millet originated in the Yellow River Basin of China, and was mainly planted in the northern part of China. Sorghum originated in Africa, and there is also a saying that it originated in China; Soybean is native to Yunnan-Guizhou Plateau in China. At present, the main producing areas are northeast and north China.
There is another explanation for the "five grains":
That is, in the previous "five grains", hemp was included, but there was no rice. This is because ancient China developed earlier in the north, and rice was planted less in the north. With the social and economic development in the south of China, the position of rice in China's grain production is becoming more and more important. Moreover, hemp is a fiber crop, and grains refer to grain crops, so grains refer to grain crops with shells in the future.
In modern times, the whole grain refers to the main grain crops, including rice, wheat, corn, beans (mainly soybeans) and potatoes (sweet potatoes and potatoes).
So now there is a kind of "small miscellaneous grains" in society, and what does it mean?
At present, small miscellaneous grains refer to a kind of small grain and bean crops, which generally have a variety of grains and beans with short growth period, small planting area, special planting area and method and multiple uses. Its characteristics are small, few, special and miscellaneous. Such as sorghum, millet, buckwheat, oats, barley and coix seed, and beans include kidney beans, mung beans, red beans, broad beans, peas and cowpeas.
In fact, in daily life, in addition to the refined flour of rice and wheat we eat, such as corn, beans and potatoes also belong to coarse grains or coarse grains.