How large is the potato harvest? 200 million mu of output is equivalent to one summer grain harvest

Why should potatoes be made into a staple food? Science and Technology Daily reporter talks with Dai Xiaofeng, head of the National Potato Staple Food Research Group and director of the Institute of Food Science and Technology at the Chinese Academy of Agricultural Sciences.

Reporter: How is a staple food defined?

Dai Xiaofeng: According to the internationally accepted definition, staple grains have "four major" characteristics: large area, large-scale cultivation, a sufficiently large output, and the ability to be stored for a long time over a relatively large region.

Measured by this standard, potatoes excel in every single aspect.

At present, the national potato planting area is about 86 million mu. Although it is not on the same order of magnitude as corn, rice and wheat, it certainly counts as large-scale cultivation. Calculated at the current domestic average yield of a little more than one ton per mu, the national potato output is about 96 million tons, equivalent to about 20 million tons of potato flour, which is 1/5 of the national total summer grain output.

A staple grain must at least be able to be stored year-round, and being resistant to storage is precisely one of the potato's strengths. After dehydration and drying, potatoes are ground into flour, called potato flour, which generally can be stored for seven or eight years, far exceeding rice, flour and corn. Buyers are willing to purchase it, it is easy to store, losses are small, and it is easy to make money from it - this is an extraordinary market advantage.

Reporter: Speaking of nutrition, by the usual understanding, isn't a potato just starch? What special value could it have?

Dai Xiaofeng: The humble little potato is actually "a treasure from head to toe": compared with the existing three major staple grains, it has a lower carbohydrate content, so it is low in calories, and its total sugar content is also low, making it especially suitable for people with the "three highs"; but it has a high dietary fiber content, making it especially suitable for Chinese people, among whom "nine out of ten men have hemorrhoids"; at the same time, it is high in various vitamins and minerals essential to the human body, especially calcium, selenium, iron, zinc and others that Chinese people are prone to lacking. It can be said that "whatever Chinese people lack, it has."

Reporter: Eating potatoes has so many benefits, so we can just gradually treat it as a staple food. Why then is it said that making potatoes a staple food is a strategic and overall measure?

Dai Xiaofeng: Under the heavy pressure of "twelve consecutive increases" in grain output, relevant decision-makers are thinking: Is our agriculture sustainable?

At present, national industrial and urban water use accounts for 30% of the total, while agricultural water use accounts for nearly 70%, and of that, effective water use accounts for only 1/3. This is especially true in the North China funnel area, the largest region suitable for growing potatoes, where water shortage is particularly severe. Yet the potato happens to be a crop that is drought-tolerant, low-temperature-tolerant, salt-alkali-tolerant, and at the same time has a short growing period and high yield. Another strong advantage of the potato is that it saves labor, which also has particularly important significance in today's China: large-scale industrialization and urbanization have brought about a widespread and prominent "labor shortage" problem in rural areas. "Grow whatever is least troublesome, and grow it in whatever way is least troublesome" - from south to north, this is unavoidable.

The second region suitable for potatoes is the area along the famous "Hu Huanyong Line", that is, the line from Heihe in Heilongjiang to Tengchong in Yunnan, known in meteorology as the arid and semi-arid zone, where the effective accumulated temperature is also insufficient for ordinary crops, and large tracts of potential farmland have not been put to use.

There is also the third region, the winter fallow fields in the south, about 270 million mu, of which at least 170 million mu can be used to grow potatoes.

With these three major blocks, plus the existing 86 million mu, it is entirely possible for the whole country to add 200 million mu of potato planting area. These 200 million mu will not compete with the other three major grain crops for land, water, labor, fertilizer or pesticides. Calculated at an average yield of 2 tons per mu, 400 million tons of dedicated potatoes can be harvested in a year, equivalent to 80 million tons of potato flour. What kind of concept is this? It is equivalent to adding one summer grain harvest. This is a remarkable contribution - it eases the pressure on food security, adjusts the planting structure, increases farmers' income, and improves the ecological environment.