The remains of carbonized rice unearthed from Hemudu Neolithic Site in Yuyao, Zhejiang Province and Luojiajiao Neolithic Site in Tongxiang are about 7000 years ago. The ancestors of these sites have been engaged in relatively settled farming life, so it dates back to the emergence of rice farming based on migration earlier
According to more than 30 years of archaeological excavations, more than 40 Neolithic sites have been discovered in China, especially in southern Jiangsu and northern Zhejiang in Taihu Lake area, followed by Hubei Province in the middle reaches of the Yangtze River, and the rest are scattered in Jiangxi, Fujian, Anhui, Guangdong, Yunnan, Taiwan Province and other provinces. Remains of the late Neolithic age have also been found in Henan and Shandong provinces in the Yellow River basin. The unearthed carbonized rice (or rice) can be divided into indica rice and japonica rice, which shows that the differentiation of indica rice and japonica rice has already appeared as early as the primitive agricultural period. Most of the rice seeds mentioned above are older than those unearthed in other parts of Asia, which proves the independent origin of rice seeds in China.
Since rice originated in the south of China, it has been the staple food of people in the Yangtze River valley and its south since the Stone Age. After the Tang and Song Dynasties, some rice-growing areas in the south further developed into national rice supply bases. In the Tang Dynasty, Han Yu said that "there are nineteen places in the south of the Yangtze River", and there were also folk sayings that "Suzhou Lake is ripe and the world is full" and "Huguang Lake is ripe and the world is full", which fully reflected the importance of rice production in the south of the Yangtze River to supply the national food demand and ensure the government's fiscal revenue. According to Tiangong Wu Kai's estimation, rice accounts for about 7/ 10, wheat and millet account for 3/ 10, and rice mainly comes from the south. Although rice was planted in the Yellow River basin as early as the late Neolithic period, the rice planting area increased and decreased, and its proportion was always lower than that of wheat, millet and millet.