When were onions introduced into China?

Onions, also known as ball onions, onions, jade onions, etc., are biennial herbs of the lily family. Prostaglandin A can reduce peripheral vascular resistance and blood viscosity, and can be used to lower blood pressure, refresh the brain, relieve stress and prevent colds. It can also clear oxygen free radicals in the body, enhance metabolic ability, anti-aging, prevent osteoporosis and so on. Let's take a look at when onions were introduced into China.

When will onions be introduced into China?

Onions are native to Central or Western Asia. There are pictures of harvesting onions in ancient Egyptian stone carvings in 1000 BC, and then spread to the central sea. In the Western Han Dynasty, Zhang Qian passed through the Western regions and brought back many species from the Western regions. At that time, there were already records of growing onions in the Western regions. After the great geographical discovery, it spread from Europe to the world. It was introduced into North America in the 16th century and spread to Japan in the 17th century. In the 18th century, "Lingnan Miscellaneous Records" recorded that onions were introduced into Macao by white Europeans and planted in Guangdong.

Where is the origin of onions?

Onions are widely cultivated all over the world, and there are many different varieties that have been used in food all over the world. The producing areas of onions in China are mainly distributed in Jinxiang, Yutai, Shanxian and Pingdu in Shandong, Fengxian in Jiangsu, Jiuquan and Wuwei in Gansu, Yuanmou, Dongchuan in Yunnan, Xichang in Sichuan, Hengchun, Fenggang and Checheng in Taiwan.

What are the growth conditions for onions?

1. Temperature: onion has strong adaptability to temperature. Seeds and bulbs can germinate slowly under 3-5 ℃. The optimum temperature for seedling growth is 12-20 ℃, 18-20 ℃ and 20-26 ℃, respectively. Healthy seedlings can tolerate the low temperature of-6-7 ℃.

2. Illumination: onion is a long-day crop, which needs more than 14 hours of long sunshine during bulb expansion and bolting and flowering. Under the condition of high temperature and short sunshine, only long leaves can not form onions. The suitable light intensity of onion is 20,000 ~ 40,000 lux.

3. Moisture: onions should be provided with sufficient water during germination, seedling growth and bulb expansion, but water should be controlled at seedling stage and before overwintering to prevent seedlings from growing and suffering frost injury. The leaf body is resistant to drought and is suitable for 60% to 70% humidity.

4. Soil: onion has strong adaptability to soil, and it is suitable to use neutral loam with loose fertility and good aeration. Sandy loam is easy to get high yield, but clay loam has full bulb, good color and storage resistance. The ability of root system to absorb fertilizer is weak, and sufficient nutritional conditions are needed for high yield.