Off-season cultivation of seed Sweet Potato

In order to improve the economic benefit of sweet potato, in addition to post-natal deep processing, sweet potato can also be put on the market early through out-of-season cultivation. This paper introduces two out-of-season cultivation techniques.

1. Sweet potato cultivation techniques on the market from May to June.

The method of storing water between ridges in greenhouse and small arch shed is adopted to improve the effect of heat preservation. It can be planted from December to January of the following year. The virus-free seedlings from stem tips were cultivated in a small arch shed, and the yield was 1300kg per 667m ~ 2 in May. The income is much higher than conventional planting.

Key points of cultivation and management: in a small arch shed with a width of about 150cm, two ridges (each ridge head 70cm) were covered with a wide film, and then irrigated in the ridge and furrow with soil (water demand was about 17t per 667m2). The long seedlings with 7-8 unfolded leaves were inserted horizontally, and the temperature in the small arch shed was kept in the range of 5-35 ℃ by ventilation. If the outside temperature rises, the side of the greenhouse can be opened for ventilation. Remove the small arch shed in the greenhouse in early March, open both sides of the greenhouse in mid-March, remove the top greenhouse in early April, take the temperature in the middle of April as standard, and make appropriate adjustments according to meteorological conditions. If the small arch shed is more than 40 ℃ for a long time, coupled with the lack of light, the potato skin will become lighter, so if there is no harm caused by late frost, the greenhouse can be opened early. The early maturing varieties with good root expansion and good shape of potato tubers should be selected under the condition of low temperature.

Cultivation techniques of fresh potato on the market from February to August

With reference to vegetable cultivation methods, seedlings can be inserted from late March to early April. Potato seedlings were taken from 5-6 short seedlings cultivated in the electric hotbed in greenhouse from January to February. The small arch greenhouse can cover two small ridges (ridge width 65-70cm), or only one large ridge (ridge width 100-120cm). Pour thin dung water after insertion, cover the plastic film after survival, and so on when the temperature is high in the small arch shed on a sunny day, pick out the potato seedlings with holes in the plastic film; if the seedlings are planted in overcast and rainy days, they can also cover the plastic film first and then transplant the seedlings, and the sockets are sealed with soil, and the potato seedlings stand upright so that the leaves do not stick to the film. If the insert has not survived, in case of continuous sunny days of high temperature, it should be properly covered with grass on the film, so as not to burn the mother leaves or even cause dead seedlings. When the external air temperature is more than 20 ℃ after April, and the temperature in the small arch shed exceeds 35 ℃, the two ends and the middle side can be ventilated and cooled, and the soil temperature under the film can be adjusted to 25-30 ℃, which is most beneficial to the expansion of potato pieces.

After May, when the external temperature is more than 25 ℃, remove the small arch shed and retain the plastic film to increase the soil temperature. After entering the rainy season, it is not only conducive to drainage, but also protect the ridge soil from the impact of Rain Water. If you choose black plastic film, you can also reduce the growth of weeds; when you enter the high temperature and drought in July, plastic film mulching can reduce water evaporation and play the role of preserving soil moisture. According to the experimental results, the sweet potato harvested in August can increase production by 30% and 50% compared with no plastic film mulching, so the investment can be fully recovered.

Early-maturing varieties should be selected. If early harvest in July, 3000 plants / 667m2 should be inserted in order to reduce the number of tubers and increase the rate of commercial potatoes. If listed, it is better to insert 4000 plants / 667m2 horizontally or obliquely, which can produce 150g-300g medium-sized tubers and improve the rate of commercial potatoes.