Cultivation techniques of Potato in greenhouse in early Spring

???? Selection and Fertilization of Land

1. Selection of plots:

In order to obtain high quality and high yield of potato, it is very important to choose suitable soil for potato growth. The plot for planting potato should meet the following two basic conditions:

One is to select fertile soil, flat terrain, easy irrigation, deep soil layer, loose soil slightly acidic sandy loam or loam for cultivation.

The second is to select plots where potatoes, tomatoes, peppers, eggplant and other solanaceous crops have not been cultivated within three years to reduce the occurrence of diseases and insect pests. The former crop is preferably leguminous, cruciferous, cereal and other crops, such as soybean, rape, onion, garlic as the former crop, but also can effectively prevent bacterial wilt harm.

Thirdly, potato cannot be planted in 1-3 years on the plots sprayed with soybean sulfuron, fomesafen, metsulfuron, chlorsulfuron, ametsulfuron and atrazine.

2. Soil preparation and fertilization:

The fertilizer application amount has a great relationship with soil type and fertility. Generally, the total amount of fertilizer applied per mu is 35-50 parts of decomposed soil miscellaneous fertilizer, 100 - 150 kg of (15 - 15) 45% potassium sulfate compound fertilizer and 100 kg of biological organic fertilizer. Greenhouse potato cultivation, generally the required fertilizer will be divided into two times, once in the field before the base fertilizer, the other time in the seeding fertilizer, generally no topdressing during the growth period.

After the fertilizer is prepared, deep ploughing shall be carried out before the beginning of winter. Before ploughing, the soil miscellaneous fertilizer shall be applied at one time, and the ternary compound fertilizer and biological organic fertilizer shall be applied at half of the mu dosage respectively. Then deep ploughing about 30 cm, so that the soil frozen, weathered, reduce winter pests.

Shed construction and shed buckling

In early spring, potato planting in protected land mostly adopts three-mode cultivation mode, generally ridging (6 ridges, 8 ridges, 10 ridges) according to the width of greenhouse is an arch shed. Greenhouses are made up of steel frame greenhouses, bamboo pole greenhouses and multi-span greenhouses. It is best to arrange the greenhouses from north to south and from east to west.

The greenhouse should be built 15-20 days before potato sowing and covered with film to facilitate soil thawing and improve ground temperature.

Buckle film: the greenhouse film should be selected with a thickness of 0.06-0.12 mm without dripping film. Usually, three kinds of film should be used. The junction between the top film and the skirt film should be overlapped by 20-30 cm. The top film should be pressed outside the skirt film. The landing part of the skirt film should be sealed with soil. The pressure film line between the two arches should be tightened and fixed. When the greenhouse film is covered, it should be carried out in windless weather to avoid wind blowing, which is not conducive to covering the film or tearing the film.

The second film is preferably a polyethylene film with a thickness of about 0.03~0.04 mm, which is about 40 cm away from the top film of the greenhouse. This will form a "warm shell bladder" type of "shed in the shed". When the second film is not in use, it can be fixed on one side of the arch frame by plastic rope.

? Selection and treatment of seed potatoes

1. Variety selection:

Early spring potato varieties with early tuber setting, rapid tuber expansion, short dormancy period, high yield, high quality and disease resistance are generally selected. For example, Holland 7, Holland 15 and Holland 803 are planted with early white, Zhongshu 3, Zhongshu 5 and Eugene 885. Virus-free seed potatoes must be selected after certification, resolutely put an end to commercial potato cultivation as seed potatoes.

General early spring potato seed tuber after a long time cellaring, low body temperature, physiological function is inhibited, so that seed tuber in dormancy. If out of the cellar immediately germination sowing, often slow and not neat germination, affecting yield. Therefore, seed potato treatment should be carried out before sowing to break dormancy and facilitate early emergence.

2. Sunning seeds

There are many ways to treat seed potatoes, and drying seed potatoes is a commonly used method. Generally, 150kg seed potatoes are needed per mu. On sunny days, the selected seed potatoes are placed in sunlight at a temperature of 12-15℃ for pre-awakening to promote the potato to release dormancy. During the seed drying period, the seed potatoes are turned once a day to make the seed potatoes evenly exposed to light. In the process of turning, mixed seed potatoes with abnormal potato shapes, such as rotten potatoes, soft and black rotten diseased potatoes, abnormal potatoes, aged potatoes, bud eye necrosis, frostbite potatoes, etc., are removed. After 2 to 3 days of drying, the potato pieces can be cut into pieces according to the size of the potato pieces.

3. Seed potato germination

Germination before sowing is an important measure for potato to be listed early in spring. It can not only promote potato early emergence, but also advance potato growth period by 7~10 days, which is beneficial to avoid high temperature and aphid damage. It is a key technology for potato seed production in spring. Germination time is generally about 25 days before the local potato suitable sowing date. The method of germination has cut germination and whole potato germination. Because the top advantage of seed tubers was broken, the bud eyes on each cut piece got similar nutrient conditions after cutting, and the germination speed was fast and the size was consistent. At the same time, cutting is also a process of eliminating diseased potatoes, which not only can make the buds root quickly, but also sprout early and uniform, which is conducive to high yield, so it is widely used in production.

(1) Cutting: The time of cutting is 1~2 days before germination. If it is too early, the cutting will lose more water or cause rotten seeds.

(2) Tool disinfection: The tools used for cutting need to be prepared by one person, used in turn, and disinfected with 75% alcohol or 0.5% potassium permanganate solution before cutting.

(3) Cutting method: Because the yield of potato tail bud is very low, it is only one third of terminal bud or lateral bud. Therefore, when potato is cut into pieces for high-yield cultivation, the tail bud should be cut off. Generally, the seed potato below 50g can be sown as a whole potato, and only the tail bud can be cut off; for the seed potato of 50~ 100g, the tail bud should be cut off and then the two petals should be cut longitudinally; for the seed potato of 100~ 150g, the tail should be cut off one third first, and then split from the terminal bud, so as to cut it into 3 pieces; For seed potatoes of more than 150 grams, the seed potatoes are obliquely cut into a plurality of three-dimensional triangular small pieces along the longitudinal oblique direction according to the number of bud eyes from the tail. The incision should be close to the bud eye, which can stimulate early germination and facilitate early emergence.

When cutting with one knife, soak the other knife in disinfectant and change the knife after each seed potato is cut. When cutting to disease, rotten potato, need to stop immediately, the knife immersed in the prepared disinfectant for the second disinfection, and then change to another knife to cut again, in order to prevent the spread of disease during the cutting process.

The size of the cut pieces should be uniform, generally 25~30 grams each, and each piece should retain at least one sound bud eye.

Spread the cut seed pieces in the leeward sun and dry the cut in bright water to promote wound healing. In order to avoid potato blade infection, and prevent seedling disease and underground pest damage, it is best to carry out chemical seed dressing.