Technical specification for production of pollution-free purple potato

On July 28, 2016, Hengshui quality and Technical Supervision Bureau issued the "Technical regulations for pollution-free Purple Potato production" as the local standard of Hengshui City. The specific technologies are as follows:

I. scope

This standard stipulates the terms and definitions of technical regulations for pollution-free purple potato production, producing environment, soil disinfection, cultivation techniques, weed control, chemical regulation, pest control, harvest, seed potato storage and other planting techniques.

This standard is applicable to the open field cultivation of pollution-free purple potato in Hengshui city.

II. Soil disinfection

The selection of soil disinfectants should meet the requirements of GB/T8321. (1-9) and NY/T2798.2. Apply 500 to 1000 grams of highly efficient soil disinfectant and 15 kilograms of soil to spread evenly to the surface, and then turn the soil to control soil-borne diseases such as stem nematode disease and root rot.

III. Cultivation techniques

1. Variety selection. It is appropriate to select varieties with high yield, high quality, disease resistance and suitable for local cultivation, such as super purple potato, purple potato king, mountain purple, black purple potato, violet and so on.

The selection of seed potato should meet the relevant requirements of GB4406. The first-generation and second-generation purple potato varieties bred in the good breeding base of sweet potato breeding units were selected as seed potatoes, and the tubers with bright and smooth skins, disease-free, disease-free, free from freezing injury and wet damage were selected to eliminate miscellaneous potatoes. The suitable size of seed potato is 150 to 250 grams.

Seed potato treatment: seed potatoes or seed plants were soaked in 50% carbendazim wettable powder 500x solution or 50% topiramine wettable powder solution for 10 minutes for 12 minutes, and 20 ℃ ~ 30 ℃ warm water was used when dispensing the solution.

two。 Sow seeds and raise seedlings.

(1) site selection of seedbed. Choose the fields with leeward to the sun, fertile soil, high terrain, good drainage and convenient management, and there are no sweet potato fields planted in 2 years.

(2) the method of raising seedlings. ① hotbed breeding method: the length of the nursery bed can be determined according to the topography and needs, generally 1.2 to 1.3 meters wide and 40 centimeters deep. The bottom of the bed is required to be high in the middle, low on all sides, deep in the south and shallow in the north, so as to make the bed temperature as uniform as possible and emergence neatly. Brewing heat can choose fully mature livestock dung and crop straw and so on. The thickness of the brewed heat is 25cm 30cm, and the top layer is 4cm 5cm fine soil, which can discharge seed potato, cover 2cm 3cm fine soil, cover plastic film, build a small arch shed, cover film warming, and cover grass curtain at night. Seeding situation: (a) seeding time. In March of each year, it is suitable for lower temperature; (b) planting mode. Vertical or oblique row is adopted; (c) planting density: 20,25kg / m2. ② electric heating wire temperature control seedling method. The seedbed is 1.2 to 1.3 meters wide and 15 centimeters deep. Bed bottom discharge heating line, interval of about 10 cm, slightly sparse in the middle, slightly dense on both sides, in order to make the bed temperature as uniform as possible, cover 2-3 cm fine soil, then discharge seed potato, temperature control at about 30 ℃, cover 2-3 cm fine soil, cover film warming, a small number of seedlings unearthed, build a small arch shed, cover film, cover grass curtain at night. Planting situation: (a) planting time, which is determined according to planting needs; (b) planting mode, vertical or oblique row; (c) planting density, 20,25kg / square meter. ③ film seedling raising method. The size of the seedbed is similar to that of the heating hotbed, with a depth of about 15 cm. Seed metering: (a) seeding time, around early April; (b) metering mode, either oblique or horizontal; (c) planting density, 15,20kg / m2.

(3) seedbed management. Maintain a seedbed temperature of 30 ℃ ~ 35 ℃ and 80% relative humidity before emergence. After emergence, remove the mulch such as plastic film on the bed surface in time, keep the bed temperature 25 ℃ ~ 30 ℃, strengthen the light, water frequently, keep the soil moist, watering combined with ventilation. Refining seedlings 4-5 days before seedling collection and planting.

(4) strong seedling standard. The weight of one hundred seedlings is 50000g, the height of the seedling is 20cm, 25cm, 5 nodes, the stem is thick, the internodes are short, the leaves are thick, the top three leaves are flush, the sap is thick, and there are no diseases and insect pests. After cutting the seedlings, fertilizer and water were applied in time to cultivate the second stubble seedlings.

3. Transplant.

(1) soil preparation and fertilization. The application of fertilizer should be based on harmless organic fertilizer, combined with inorganic fertilizer. The selection of fertilizer should meet the relevant requirements of NY/T2798.2. During the whole growth period, the nutrients were mainly based on base fertilizer. About 15 days before planting, 2000-3000 kg of high-quality organic fertilizer, 10 kg of potassium sulfate, 5 kg of urea and 10 kg of diammonium phosphate were applied per mu as base fertilizer, and 2.5 kg of microecological bacteria were applied per mu. All organic fertilizers were sprinkled before ploughing, and inorganic fertilizers were applied when ridging. Before ridging, it is appropriate to plough at a depth of 25 to 30 centimeters, fully crush the soil grains, rake flat, and make ridges with a width of 35 centimeters and a height of 40 centimeters, with a spacing of 80 centimeters and 100 centimeters.

(2) planting. Seedling preparation: 3-5 days before seedling collection, properly cooling seedlings to cultivate strong seedlings, 2 days before seedling spraying protective broad-spectrum sterilization and insecticides once. Planting and precautions: (a) planting density. Spring sowing field 3000mu / mu, summer sowing field 4000mu / mu; (b) planting date. It is suitable for spring potato from late April to late May, while summer potato can be postponed to late June. (C) planting method. Oblique insertion of 2-3 nodes into the soil, exposure of about 3-4 nodes; flat insertion of 3-5 nodes into the soil, about 3 nodes exposed; (d) points for attention. The leaves of seedlings should not be damaged during planting. After planting, the roots should be watered thoroughly, and the soil should be covered within 3 days to preserve soil moisture. Irrigation should meet the relevant requirements of GB5084.