1. seed selection: to cultivate potato seedlings well, we must first choose potato seeds that are free from disease, injury and freezing. Summer potato has strong vitality, slight susceptibility to diseases, rapid emergence and high frequency, so summer potato should be selected as seed potato in production.
2. Bed-building: (1) Choose the plot with sunny and leeward, flat terrain, good drainage and low groundwater level. The seedbed should face east and west. Generally, the bed width is about 1.3 meters, and the length of the root depends on the number of potato seeds, and it is covered with plastic film.
Fill with moldy cow dung, wheat straw and broken grass (fresh cow dung is dried in advance and mashed for later use). Generally, cow dung 1 serving and straw 2/serving are used. First, a small amount of cow dung and straw are mixed evenly, and then a small amount of urine water is added. The experience of the masses is: "If you don't do it, it will be cold, and if you don't do it, it will be warm." Generally, it is better to make hot things 20-30 cm thick. After filling in the hot stuff, pat it with a shovel to keep it in a proper loose state. Then cover it with film and seal it tightly with soil. Cover with straw to keep warm at 3-4 pm. Expose to the sun in the morning on a sunny day to raise the temperature. After 2-3 days, when the temperature of the hot thing rises above 35 degrees Fahrenheit, it will be heated.
(2) Some local seedling raising methods are also adopted to cover the film arch shed.
(3) Adopt the double insurance method of heating the sunny side, make a high side at the sunny side, heat it with kang or electric heating wire, and build a small film arch shed on the sunny side.
(4) Cold-bed seedling raising method: the seed potato is placed directly on the ground without soaking hot materials, and 2-3 cm fine soil is sprinkled on the seed potato to cover the film. This method is simple, but its disadvantages are late seedling raising time and slow seedling emergence.
3. Generally, "three selections" should be made before sowing, that is, kiln selection, seed selection, bed selection and warm soup soaking before sowing. The water temperature of potato seeds should be controlled at 56-58 degrees Celsius. After the launch, the basket containing potato seeds should be raised and lowered to 565,438+0-54 degrees Celsius within two minutes, the water temperature should be balanced, and the seeds should be soaked for ten minutes, generally 200 kilograms. You can also soak the seeds with drugs, and soak the seeds with 50% 800- 1000 times liquid medicine or 500 times carbendazim for 5- 10 minutes. When sowing, we should pay attention to the fact that the sweet potato head is up, the sweet potato head is uneven, and the sunny side faces north, making an angle of 30 degrees with the ground, and the potato spacing is about 2 cm. After sowing, sprinkle a layer of sand or soil, fill the gap and water it, so that the bed soil is completely wet (but it should not be wet enough to brew hot things). Finally, cover it with a film and seal it with mud, with 30 kg of original seeds per mu, 35 kg of improved seeds, and 20-25 kg per square meter (if you don't have time to build the bed in advance, you can also put potato seeds at noon on sunny days and immediately keep warm).
Second, seedbed management.
(1), temperature and heat preservation should be done in the early stage of seedling raising. Put a thermometer on the bed. Accelerating germination at high temperature before emergence, increasing bed temperature and preventing the occurrence of black spot disease. The temperature of the potato layer should be kept at 32-35 degrees Celsius, and when the temperature reaches 40-42 degrees Celsius around noon on sunny days, the temperature in the film should be reduced. After emergence, the temperature of potato layer in seedbed should be kept at 25-30 degrees Celsius, and the temperature in film should not exceed 35 degrees Celsius. Otherwise, it will affect the growth of potato seedlings or burn them.
(2) adjust moisture. If the soil is dry, it can be lightly watered. If you water too much, it will obviously reduce the temperature and delay the emergence time. If the water is insufficient, it will cause the bed temperature to be too high, which will cause the seedlings to wither, make the potato seeds sweet, and master light, diligent, even and light watering to wet the bed surface.
(3) hardening seedlings. To obtain high yield, it is most important to cultivate strong seedlings. Potato seedlings should be short, thick and big. When the seedling height is 13.2- 16.5 cm, the plastic film should be removed to make the seedling hard. If there is no frost at night, you don't need to cover the seedbed, dry it overnight, and dry the seedlings directly on the third and fourth days to adapt the potato seedlings to the field environment. Cut seedlings to prevent the spread of black spot disease. The second day after cutting, according to the seedling situation, when there is no fertilizer or water, immediately water and apply nitrogen fertilizer (urea), and cover with agricultural film to raise the temperature, which can achieve the effect of seedling raising. If there are diseases in the seedling stage, carbendazim or nail support can be sprayed 500-700 times or poured 1000 times. After planting spring potatoes, if you want to plant summer potatoes, you should first prepare the nursery, discharge the seedlings from potato seeds to the nursery and plant them in the recommended area of wheat. When this happens, the cultivated potato is Miao Zhuang, which has high survival rate and high yield. You can't cut thousands of seedlings in the spring potato field, otherwise it will affect the yield reduction of spring potatoes by more than 40%.
Third, high-yield planting and transplanting techniques of sweet potato
1. Transplanting time: Spring potatoes should be transplanted from mid-late April to early May. When the local average temperature is stable, the temperature required for sweet potato growth is above 15 degrees, and the shallow ground temperature reaches 17- 18 degrees. It is not allowed to grow too early, lest the seedlings grow slowly or be seriously short of plants. After the potato seedlings survive, the ridge surface will be finely flattened to facilitate heat preservation and moisture retention. Spring potatoes should not be planted too early or too late. After the suitable planting period, the yield will be reduced by about 1% every night, especially for summer potatoes, which will be reduced by more than 2% every night. Planting early at the right time and prolonging the growth period can increase nutrient accumulation, promote the early development of stems and leaves, form suitable groups in the early growth stage, and make the root tuber grow early and continue to expand for a long time. Due to the prolonged growth period, the nutrients accumulated in the root tuber increase, so the potato tuber is large, and the sun drying rate and starch content increase. Early planting can enhance the ability to resist disasters. In the case of severe drought, we can make full use of climatic conditions, promote the early development of stems and leaves, increase the green coverage of soil surface, make the root system develop deeply and alleviate the impact of drought. Generally, it should be planted in the middle of April when it rains (cutting after rain is the best).
2. Fixed value density:
(1) Single-row spring potatoes per mu 1500 holes, with two plants per hole, i.e. 3,000 plants per mu, with row spacing of 35cm, row spacing of 90cm and ridge height of 45cm (single plant can be planted in high-fat land).
(2) The width of the big ridge is 1.3m, the height is 40cm, and the width on the ridge is about 70-75cm. Plant two rows of seedlings on each ridge with a spacing of 57 cm. Two-plant cultivation, triangular planting, planting 1.800 plants per mu, that is, about 3600 plants (single plant cultivation can be carried out in high-fat land).
(3) Close planting method can be used on hillside and thin land, with ridge width of 60 cm, single plant cultivation and ridging.