How to do a good job in the late management of plastic film-mulched potatoes in early spring

In early spring, plastic film-mulched potatoes will gradually enter the tuber expansion period after May, at this stage, potatoes are more sensitive to water and fertilizer, high demand, and high incidence of diseases and insect pests. Next, introduce the technical key points of the late management of plastic film-mulched potatoes in early spring.

Potato

First, remove the film and cultivate the soil. When the stem and leaf of the shoot of plastic film mulched potato reached the height of about 30 cm in early spring, the tuber began to expand before and after budding. When the external temperature was stabilized at about 25 ℃, the mulching film should be removed in time. After removing the plastic film, the weeds in the ridges should be pulled out in time, and the soil should be cultivated twice in the roots of potatoes. Soil cultivation can increase potato yield and prevent the occurrence of potato tuber green skin disease.

Second, watering and fertilizing. Potato tuber expansion period, need to have sufficient water and fertilizer supply, when potato tuber has walnut size, can be combined with watering topdressing, potatoes belong to potassium-loving crops, potash fertilizer demand is large. During watering, 20 kg of nitrogen and potassium fertilizer was applied per mu, once every 10 days, and twice in a row. In case of continuous drought, we should pay attention to timely watering potatoes to prevent soil drought from affecting the expansion of potato tubers.

Third, control pests. Potatoes enter the later stage of growth, the main pests are aphids and grubs and other pests. Aphids harm the leaves, suck the juice of potato leaves, spread potato virus disease, and affect the yield of potatoes. 10% imidacloprid 800 times solution can be used for spray control, once every 7 days, twice in a row. Grub is a major underground pest that affects the yield of potatoes, gnawing on potato tubers, resulting in a decline in yield, poor commerciality and affecting planting income. The control method is to choose phoxim to irrigate the root, the dosage is 1-1.5 kg per mu, combined with watering before and after evening, it can have obvious control effect, improve the yield and commerciality of potato, and increase the planting benefit.