Breeding seedlings is the key to high yield of sweet potato. Only when the seedlings are strong and planted early, can we lay a good foundation for high yield and harvest. The following is the introduction of sweet potato seedling technology.
We are using sweet potato to raise seedlings. 1. Seedling bed preparation
1. Selection of seedbed: choose the sandy loam with leeward to sunny, good drainage, low groundwater level, flat terrain, loose and fertile, disease-free sandy loam as the seedbed.
2. Seedbed specification: the soil moisture of seedbed is 1.6m in north-south direction, the width of soil moisture is 1.3m, the width of drainage ditch is 30cm, the depth of ditch is 30cm, and the soil moisture surface is suitable for flat soil moisture; the length of seedbed is determined according to the terrain and sowing amount, so as to facilitate management.
3. Seedbed preparation and fertilization: after selecting the seedbed, deep ploughing and harrowing are carried out in early spring (before February 4). Combined with deep ploughing, 1500 kg of decomposed organic fertilizer, 20 kg of compound fertilizer and 50 kg of calcium superphosphate are applied to fully mix the bed soil and fertilizer. The soil preparation requires that the soil moisture is flat, the soil is fine, the ditch is straight, and the ditch is connected, so as to lay a good foundation for the cultivation of strong seedlings.
4, seedbed treatment: in order to prevent soil borne bacteria, after leveling the seedbed, disinfectant can be seeded with 2% enemy solution of pine solution. 2 kg can also be used for enemy Songyuan powder.
2、 Sowing
1. Determination of Sowing Date: the minimum temperature of sweet potato germination is 16 ℃, when the soil temperature (10 cm depth) is stable through 16 ℃, sowing can be carried out. The specific sowing time depends on the first transplanting period, generally 45-60 days before the first transplanting.
2. Selection of seed tuber: before sowing, the seed tuber must be selected, and the tuber with the characteristics of this variety, no diseases and pests, no damage, moderate size (4-6 double), proper shape, smooth skin and no freezing injury. The selected tubers were soaked in 2% carbendazim solution for 20 minutes, and then removed and dried.
3. Sowing
(1) Sowing rate: the sowing rate is different with the size of tuber. There are more large tubers and large amount of seeds; while there are more small tubers with less seed amount, generally 1000-1200 kg seeds per mu.
(2) Sowing specification: 20cm × 40cm, i.e. plant spacing 20cm, row spacing 40cm, 6 potato seeds per row.
(3) Sowing method: there are three sowing methods of sweet potato: horizontal row, oblique row and straight row. There are more seedlings on each seed of horizontal row, which can make full use of the limited seedbed area and provide enough seedlings for large-scale production. At the same time, due to the different size of tubers, we should select them according to their classification, and arrange the large tubers closely and the small ones sparsely. When sowing, it is required that the potato seeds should be evenly arranged, so that the thickness of the soil covering on the tuber is consistent, and the emergence is neat, which is convenient for seedling bed management.
4. Covering soil: the thickness should be consistent when covering soil, and it is appropriate to cover the seed tuber tightly. For the seedbed with more underground pests, 2 kg of greenbelt Congqing or 4 kg of 3% phoxim granules (baodide) should be used to control the underground pests in combination with the soil covered mu, so as to improve the emergence rate and promote the uniformity, uniformity and strength of seedlings.
5. Irrigation: timely irrigation after the seedlings are covered with soil, which can be manually poured or furrow irrigation. In furrow irrigation, it is better to reach the edge of soil moisture instead of flood irrigation. For the field with high groundwater level, timely drainage should be conducted after irrigation to prevent seed potato from rotting.
6. Film mulching: in order to promote the early growth and rapid development of seed tubers, increase temperature and humidity to achieve even, even and strong seedlings, and timely cover the film after irrigation. 1.5m-wide film is used for covering. When covering the film, both sides should be tightened and straightened, close to the soil surface, and the surrounding should be compacted and compacted. The light transmission surface should not be less than 1.3m, and the amount of film used per mu should be 3kg. At the same time, 1000 times of acetochlor or atrazine herbicide was used to seal the grass in the cover, effectively killing weeds in the field.
3、 Seedbed management
1. Check and replenish seedlings: after emergence of seed tubers, timely check seedlings to make up for deficiencies, and timely reseeding when there is a lack of pond, so as to achieve complete seedlings.
2. Releasing seedlings by breaking film: the ability of top membrane of sweet potato seedlings is weak. In order to avoid the seedlings being burned by membrane, the seedlings should be released timely after emergence.
3. Water management: 20 days after planting, according to the degree of soil moisture, add water, can be poured manually or furrow irrigation. In furrow irrigation, it is appropriate to let water run through the bottom of drainage ditch instead of flood irrigation.
4. Fertilization: 20 kg compound fertilizer per mu was applied after the seedlings were seeded and irrigated. Fertilizer can be broken film hole application, can also be before irrigation fertilizer evenly distributed in the drainage ditch, combined with irrigation.
5. Other management: in the whole growth period of the seedbed, timely attention should be paid to remove the diseased seedlings and rotten potatoes to prevent the spread of the disease; if the soil is shallow and the potato chips are exposed, it should be covered tightly in time to facilitate the emergence of seedlings. At the same time, attention should be paid to weed control and cultivation management, as well as time seedlings and topping (topping), so as to promote branches and increase the emergence of seedlings.
6. Picking seedlings: remove the film and refine the seedlings when they grow to 6-7 knots, so as to improve the survival rate of transplanting. 45-55 days after sowing, when the seedling height is 20-30cm, the seedlings should be picked in time. Too late seedling picking, crowding of potato seedling and poor growth of lower seedling affected the emergence of next crop. High cutting method was used to harvest seedlings, 1-2 stubbles were left to facilitate regeneration, and irrigation was applied after each seedling harvest. The top dressing is mainly quick acting nitrogen fertilizer urea, 10 kg / mu, sprinkling or watering, but the seedling burning should be strictly prevented.
sow
The seedlings are growing