Potato protein has high nutritional value. Protein content in potato tuber is about 2%, and protein content in dried potato is 8% ~ 9%. According to the research, the protein nutritional value of potato is very high, its quality is equivalent to the protein of eggs, and it is easy to digest and absorb, which is superior to protein of other crops. Moreover, the protein of potato contains 18 kinds of amino acids, including various essential amino acids that cannot be synthesized by human body.

The growth process of potatoes:

1. Sleep period

After harvesting, potatoes can not germinate for a long time in an environment suitable for germination, which belongs to physiological natural dormancy and is an adaptability to adverse environment. When the top of stolon stops polar growth and tuber begins to swell, tuber dormancy begins. The length of dormancy period is related to the storage of tubers and whether they can emerge in time after sowing, so it is also related to the yield. The dormancy period of potato is greatly influenced by storage temperature. Under the condition of about 26 degrees Celsius, the dormancy period varies from 1 month to more than 3 months due to different varieties. Potatoes can stay dormant for a long time at the temperature of 0-4 degrees Celsius. The dormancy process of potato is determined by the direction of enzyme activity and closely related to environmental conditions.

2. Germination stage

The growth of potato begins with the germination of buds on tubers. Buds and seedlings can grow obviously only when tubers are released from dormancy. The germination period is from germination to emergence, and the first section of the main stem grows. The growth center of germination stage is bud elongation, rooting and stolon formation. Nutrition and water mainly depend on seed potato, which is supplied in the order of stem, leaf and root. The speed and quality of growth depend on potato seeds and the environmental conditions required for germination. The growth time varies from 1 month to several months due to different dormancy characteristics, cultivation seasons and technical measures.

3. Seedling stage

From emergence to the flattening of the sixth or eighth leaf, the growth of 1 leaf sequence is completed, which is called "clump tree", which is the second growth stage of the main stem and also the seedling stage of potato. The seedling stage is short, whether it is spring or autumn, it is only half a month.

4. Tree emergence stage

From the cluster to the twelfth or sixteenth leaf, the early-maturing varieties bloom in the first inflorescence; Late-maturing varieties bloom in the second inflorescence, which is the flowering period of potatoes and lasts about 1 month, which is the growth of the third segment of the main stem. The main stem began to rise sharply in the growth period, accounting for about 50% of the total height; The main stems and leaves have all been built, and branches and branches are expanding. The root system continues to swell, and the tuber expands to the size of pigeon eggs. There is a turning stage of growth center at the seedling stage of trees, and the end point of the turning stage is that the ratio of stem and leaf dry matter to tuber dry matter reaches balance.

5. Potato growth period

That is, the tuber formation period. After the completion of the tree growth period, it will enter the tuber-bearing period with tuber growth as the main factor. During this period, the growth of stems and leaves decreased day by day, the basal leaves began to turn yellow and wither, the organic nutrients in various parts of the plant were continuously transported to the tuber, and the tuber expanded rapidly, especially on 10 day after flowering. The duration of potato seed setting is controlled by climatic conditions, diseases and variety maturity, generally 30-50 days.

Growth conditions:

Potato likes to be cold and cool, and it is a crop that likes low temperature. The formation and growth of underground potato requires a loose, breathable, cool and moist soil environment.

Temperature requirements for potatoes: the optimum temperature for tuber growth is 16℃~ 18℃, and when the local temperature is higher than 25℃, tuber growth stops; The optimum temperature for stem and leaf growth is 15℃~25℃, and it will stop growing when it exceeds 39℃.