Answer: Ming dynasty ~

In the middle of16th century, corn was introduced into China in three ways, namely, from Persia and Central Asia to China and Gansu, and then into the Yellow River basin. Southwest land from India, Myanmar to Yunnan, and then to Sichuan and Guizhou; The Southeast Sea routes Southeast Asia to Fujian, Guangxi and other coastal provinces, and then extends to the mainland. From the mid-Ming Dynasty to the Qing Dynasty, corn was only planted in a small area in some provinces of China in these two hundred years, and it was still in the stage of being recognized by the public. From the middle period of Qianlong to Jiaqing and Daoguang years, corn was popularized on a large scale. At this time, people began to realize the wide adaptability and high-yield significance of corn, and planted it in succession. After Jiaqing, corn was widely planted in China, among which refugees played an important role in the spread of corn. From the late Qing Dynasty to the Republic of China, except for the in-depth development of corn planting in mountainous areas of southern provinces, corn planting in North China Plain entered a stage of great development, and corn replaced some old traditional low-yield crops and became one of the main food crops for people in the middle and lower reaches of the Yellow River. In Qing Dynasty, corn was planted in mountainous and hilly areas, and then gradually spread to plain areas. First in underdeveloped areas, then in developed areas; The south is more than the north, and the mountains are more than the plains. In Qing Dynasty, corn concentrated areas were in the mountainous areas of Shaanxi, Hubei, Sichuan, Hunan and Guangxi in the middle, Guizhou and Yunnan in the southwest, and some mountainous areas of Anhui, Zhejiang and Jiangxi in the southeast. Corn concentration areas in North China and Northeast China were mainly formed from the late Qing Dynasty to the Republic of China. Sweet potato was introduced from Southeast Asia to Fujian, Guangxi and other provinces along the southeast coast of China in the late16th century. The first route is that Chen Yi and Lin Huailan are introduced from Vietnam to Dongguan and Dianbai respectively. Another ship was introduced into Quanzhou, Fujian by Wenling Ocean Ship via Nan 'ao Island. Then Chen Zhenlong brought the seeds from the Philippines to Fuzhou. After sweet potato was introduced to China in Wanli period of Ming Dynasty, it was confined to Fujian and Guangdong for nearly a hundred years. /kloc-began to spread to Jiangxi, Hunan and other provinces and coastal areas of Zhejiang and Jiangsu in the late 0/7th century. /kloc-in the middle of the 0/8th century, it spread all over southern provinces and extended to the Yellow River basin and its north. In Qing Dynasty, sweet potatoes were mainly distributed in Fujian and Guangxi provinces, hilly areas of Fujian, Zhejiang, Jiangxi and Anhui, southern Hunan, Sichuan Basin and south-central Shandong. Due to the lack of historical data, there has been no unified conclusion on the time and route of potato introduction into China. To be sure, potatoes, like sweet potatoes and corn, have been brought to China many times in many ways. This paper agrees with the following viewpoints: firstly, the Dutch brought potatoes to Taiwan Province Province in the middle of17th century, and then spread them to the southeast coastal areas of China; First, in the18th century, missionaries and businessmen brought common potato varieties from Europe to China; And after entering the 20th century, with the invasion of imperialism, many new potato varieties were introduced. Until the beginning of19th century, the spread of potato was still very limited. During the late Qing Dynasty and the Republic of China, with the extension of introduction time, the expansion of popularization scope and the deepening of people's understanding, it developed initially, but the real expansion of planting area played an important role in agricultural production after the founding of the People's Republic of China. The concentrated potato producing areas in Qing Dynasty were the southwest potato producing areas centered on the mountainous areas at the junction of Sichuan, Shaanxi, Hubei and Gansu and the north potato producing areas centered on the north of Shanxi. The main potato producing areas in Northeast China were formed after the Republic of China. When talking about tobacco or smoking, people in Qing Dynasty often quoted relevant records in Lv Yao's Lu Shu, which is the most influential text about tobacco introduction in China. This book was written about 16 1 1 year, and the tenth volume "Wrong Articles" said:

The same grass is called "light grass" in Shandong, one end is drunk early, the other end is burned with fire, and the other end is facing the mouth. Smoke enters the throat from the pipeline, which can make people drunk and prevent miasma. Someone brought Zhangzhou to plant it, and now it is more than Luzon, and it is sold in its country.

At that time, Zhangzhou tobacco was exported to Luzon, which shows that the production has reached a considerable scale. According to this, it can be inferred that tobacco was planted in Zhangzhou, Fujian at the end of16th century or the beginning of17th century, and smoking became popular. ~