How to Grow Virus-Free Potatoes for High Yield? Detailed Explanation of Key Planting Techniques

Virus-free potatoes refer to seed potatoes that have been cleared of viruses within the tuber through a series of physical, chemical, biological or other technical measures, and then tested to obtain seed potatoes that are virus-free or have minimal virus infection. The yield-increasing effect of virus-free seed potatoes is remarkable; using virus-free seed potatoes can increase yield per unit area by 30%-50%, and in high cases by 3-4 times.

To plant potatoes, choose loose and fertile soil with deep, loose layers and good drainage and irrigation conditions, planting in neutral or slightly acidic flat land or gentle slopes and sandy loam soil; it is not suitable to plant in alkaline soil. The best preceding crops for potato planting plots are sorghum, corn, wheat and gramineous grains; continuous cropping must be avoided. Plots with preceding solanaceous crops are not suitable for planting potatoes, such as tomato, eggplant, pepper and other plots; plots where herbicides such as pustral, nicosulfuron, flumetsulam, halosulfuron-methyl, quinclorac, etc. were used in the previous year are also not suitable for planting potatoes.

????I. Seed Potato Treatment

1. Dormancy breaking, sunning and sprout promotion

Take the seed potatoes out of the cellar about 30 days before sowing, place them indoors under scattered light at 12°C-15°C for sunning; turn them 1-2 times during the sunning period; when the buds grow to show white sprouts, they can be cut into pieces.

2. Cutting into pieces

Cut into pieces 1-2 days before sowing; the cutting knife should be disinfected with alcohol or other agents; when cutting, select vigorous terminal buds, cut open the dense terminal buds, then cut into three-dimensional pieces in spiral order; each piece should carry 1-2 buds, and the piece weight should not be less than 30 grams; when the piece is large, do not leave potato flesh behind; small potatoes can be sown whole. The cut seed pieces can be placed in a cool, dry place and sown within 2-3 days.

????II. Field Management

1. Weeding

After the seed potatoes emerge, weed the field in time, either by manual weeding or by spraying herbicide. Herbicide spraying is mainly after emergence, using DuPont Baocheng when weeds have 2-3 leaves, at 4-5 bags per mu (2.5 grams/bag).

2. Cultivation, hilling and watering

? Cultivation and hilling should be completed before the potatoes flower, combining shoveling and plowing, that is, three shovelings and three plowings. When closing the rows, the ridges should be built into "wide-shoulder ridges", not "pointed-top ridges", so that when tubers form, the potatoes are not likely to be exposed, and the tubers can benefit from soil nutrient supply. Potatoes flowering enter the tuber formation stage; if drought occurs, irrigate in time, otherwise yield will be seriously affected.

????III. Soil Fertilization

Potatoes are a crop that likes water and fertilizer; fertilization should follow the principle of organic fertilizer as the main and chemical fertilizer as the supplement. Fertilization method: apply sufficient basal fertilizer at one time according to soil fertility; fully decomposed organic fertilizer should be applied deeply or evenly scattered in the furrows before sowing. While applying organic fertilizer, you can apply diammonium phosphate, urea, potassium sulfate chemical fertilizer or compound fertilizer containing the three elements nitrogen, phosphorus and potassium; the best ratio of nitrogen, phosphorus and potassium fertilizer is 2:1:4. After applying nitrogen, phosphorus, potassium or compound fertilizer, cover with a thin layer of 3 cm of soil, then sow the seed potato sprout pieces, strictly avoiding direct contact between sprout pieces and chemical fertilizer to avoid burning the sprouts. After fertilizing and planting the seed potato sprout pieces, close the ridges and cover with soil in time. Zhang Yanyong