Main cultivation techniques of Purple Sweet Potato

I. the choice of land

Most of the purple sweet potatoes are middle and late maturing varieties, the tuber expands rapidly and the yield forms late. The cultivated land not only requires high soil fertility, but also the soil texture should be light soil or sandy soil, and the flatness of the land and the conditions of drainage and irrigation should be better. Purple sweet potato has good adaptability, but in the continuous cropping land with a history of nematode and black spot, diseases may occur, resulting in reduced yield, so attention should be paid to soil disinfection and insecticidal treatment.

II. Selection of varieties

At present, there are many varieties of purple sweet potato in China, which should be selected or introduced according to local soil conditions and planting purpose. For health care and fresh food, you can choose Jingshu 6, Ji 18, Xu 22muri 5, etc.; for dry powder processing, you can choose Xu Zi 1, strange purple, mountain purple, etc.; those with high soil fertility can choose Jingshu 6, Ji 18, Xu Zi 1 with great potential for yield increase; and mountain purple, strange purple with strong adaptability, etc. can be selected for low fertility soil.

III. Cultivation techniques

Purple sweet potato should be planted in the suburbs of Beijing by ridging and plastic film mulching and flat planting. Spring potato ridge distance 75-80cm, summer potato 70-75cm, ridge top width 15-20cm, ridge height 25cm, covered with 800 × 0.008mm black or transparent polyethylene film. Before raising the ridge, 50 kg of basic fertilizer (N:P:K=8:7:10) compound fertilizer and 5 kg of poison valley mixed with 0.2% phoxim solution were applied per mu, and the soil was loosened and applied underground. When using organic fertilizer as base fertilizer, it must go through full ripening and 3 square meters per mu according to the conditions. The purchased or self-bred sweet potato seedlings were properly graded before planting, showing consistent centralized planting, so as to ensure orderly and balanced growth in the field. Purple sweet potato seedlings are relatively robust, and the parts that have adventitious roots should be cut off before planting, which can not only promote the rapid concentration of adventitious roots in the lower internodes, make the tuber neat and concentrated, but also reduce the height of seedlings and slow down the seedlings as soon as possible. The seedlings are planted in the middle of the ridge, clamping the middle of the seedlings with the thumb and index finger, and the middle finger cuts down the plastic film, and at the same time it opens into a pit with a diameter of 5cm and a depth of 4cm. The roots of the potato seedlings are fixed by soil pressure at the bottom of the pit, and 5 leaves are exposed on the ground. The distance between plants is determined by the distance between ridges. The total number of seedlings planted per mu is 3200 Mel 3400 for spring potato and 3700 for summer potato. Each seedling pit is watered twice, with a total amount of 500,000ml, then the pit is flattened, and the cracks in the film are sealed and pressed.