Field Management of Sweet Potato for growing vegetables

1. Check seedlings and replenish seedlings: check the survival of potato seedlings 7 days after planting, and replant strong seedlings in time.

2. Topdressing: after spring potato planting, 30ml / mu (30kg / mu) compound fertilizer, 30 kg / mu (N:P:K=10:7:8), 30 kg / mu compound fertilizer, combined with topdressing, soil loosening between ridges, intermediate tillage and weeding.

3. Drought resistance and waterlogging prevention: spring potato is in the ridge closure period before and after the wheat harvest in mid-June, which is easy to be drought. if wilting is found in the middle and upper leaves, it should be watered in time to resist drought. The method of watering is alternate ditch irrigation or sprinkler irrigation, using about 30 cubic meters of water per mu. Prevent stagnant water in the ditch and discharge at any time after entering the rainy season.

4. pest control: purple sweet potato has good adaptability, and serious diseases and insect pests will not occur if planted on stubble ground. All kinds of leaf-eating pests are easy to occur before and after autumn, so pyrethroids with high efficiency and low toxicity should be used to control them in time.

5. Harvest: with the shortening of sunshine time and the decrease of air temperature after autumn, the root of sweet potato expands rapidly. In order to strive for higher yield, purple sweet potato (except those on the market preemptively) should be harvested as late as possible, delayed until the ground temperature around National Day is 13 ℃ and 15 min, and stored with transportation. The cultivation of vegetable sweet potato generally refers to the fresh and tender stems and leaves with about 12cm below the growth point as vegetables. The tender stems and leaves of sweet potato are rich in vitamin C, dietary fiber, crude protein, a variety of minerals and some special nutrients. According to the Chinese Academy of Preventive Medicine, sweet potato leaves rank first among 13 nutrients such as protein, calcium, phosphorus, iron, carotene and vitamin C compared with 14 kinds of vegetables such as spinach. In recent years, the analysis of anti-cancer components and anti-cancer tests of more than 40 kinds of vegetables by the National Cancer Prevention Institute of Japan have shown that sweet potatoes for leafy vegetables have the highest anticancer activity. American scientists have found that sweet potatoes contain an active substance called dehydroepiandrosterone, which can prevent colon and breast cancer, delay intellectual decline and increase human immunity. Developed countries regard sweet potatoes as "health food" and "space food".

At present, the varieties at home and abroad are Taiwan's Tainong 71, Japan's Kanto 109 and so on. This research started a little late in China, and dual-use varieties of leaves and potatoes, such as Lushu 7, Beijing 553 and Shi 20, were selected in the late 1980s. In the 1990s, after more than ten years of efforts, Fujian Province successfully selected and bred the first new leaf vegetable special sweet potato variety Fushu 7Mui6 approved at the provincial level in China. With the in-depth understanding of the edible value of sweet potato stems and leaves, and the successful breeding of excellent leaf-vegetable sweet potato varieties, sweet potato tender stems and leaves as vegetables have quietly become fashionable. Sweet potato stem tips and tender leaves are popular nutrition and health vegetables in the vegetable markets of Japan, Southeast Asia, Taiwan and Hong Kong. The price of young leaves and shoots of sweet potatoes per kilogram in the Hong Kong market is about 100 Hong Kong dollars. In recent years, the consumption of sweet potato vegetable tender stems and leaves in our province has increased rapidly, with an average annual growth rate of about 230%. Sweet potato tender stems and leaves have generally entered medium-and high-grade hotels and gradually stepped onto the dining table of people's homes. The application and promotion area of leaf vegetable sweet potato is expanding rapidly.

At present, the cultivation of vegetable sweet potato in China is still in the initial stage. In the south, because of the long rainy season and heavy rainfall, high border cultivation is adopted: six rows of sweet potato are planted on the border with high 15cm and 1Mel 1.2m wide, and the space of 25-30cm between borders is used for drainage and picking. 1.5-20000 plants per mu, the annual growth of one planting, the production of commercial vegetables 3000kg per mu, the output value of more than 4000 yuan. The results of trial and introduction in this city since 2004 show that leafy vegetable sweet potato can be planted in open field and covered with plastic film in the suburbs of Beijing, the growth can be 150ml / 160d, the picking period is 120MU / 130d, the yield is 2000-2500kg per mu, and the yield can reach 3000-4000kg in greenhouse protected field.

The main cultivation techniques are as follows: 1. Selection of land and border: vegetable sweet potato mainly harvests stems and leaves, taking into account the characteristics of sweet potato, fertile light loam should be selected. The fertility of the soil should be high, especially in the previous crop that has not planted sweet potatoes in three years (watermelons, vegetables, corn and wheat fields). According to the climatic characteristics of the north, the specification of the border is 15cm high, 60-80cm wide, and the middle 30cm watering belt. Before the border, 2000-2500kg mature organic fertilizer and 0.2% phoxim solution were mixed with poison valley 50kg to spread, and turned into the ground with loose soil. The border surface was covered with 0.015m thick plastic film and compacted on both sides.

2. Planting: potato seedlings are planted on the top of the border, row spacing 20cm, plant spacing 12-15cm, 1.4-16000 plants per mu, seedlings are planted vertically or obliquely, and the depth of soil is 4-6cm. After planting, use kettle to order water and cover the film cracks.

3. Picking and pruning: the heart of potato seedlings is removed immediately after slow seedling to promote the formation of side branches of axillary buds. About 30 days after planting, the 12cm at the top of the new lateral branch can be harvested and packaged on the market. After that, according to the growth situation, the potato seedlings will be picked every 8 days until the first frost stops growing. Each picking should leave about 2 internodes in the stem of the branch to ensure the regeneration of new buds. At the same time, the mother stem should be repaired to remove the abnormal buds from the old stem at the bottom to ensure the ventilation and light transmission of the population and the centralized supply of nutrition.

4. Topdressing and management: in order to ensure the yield and quality of stems and leaves, one watering and topdressing should be carried out after picking twice. Topdressing should use nitrogen, phosphorus and potassium compound fertilizer or special irrigation fertilizer 10-15kg, the amount of water per mu is about 25 tons, irrigation along the picking operation belt, side infiltration into the border. After watering, the soil is loose and the weeds on the border or in the middle are pulled out at any time. Vegetable sweet potato has good adaptability, and stubble ground diseases rarely occur. If leaf-eating pests occur, biological agents with high efficiency and low toxicity should be applied as soon as possible.

5. Seed potato propagation: due to the picking of stems and leaves in the potato field, the root can not be expanded underground, and the remaining seeds must be planted separately, and the cultivation requirements of vegetable potato and common sweet potato are the same.