Potato growing process using minimum tillage method with straw covering

(Baonghean) - Potatoes have a short production cycle (within 3 months) and high productivity, which has significantly contributed to increasing income for producers. The following is the process of growing potatoes using the minimal tillage method with straw covering, a method that helps increase productivity, reduce costs, increase production efficiency, increase soil fertility and reduce environmental pollution caused by indiscriminate burning of straw.



Growing potatoes using the minimum tillage method. Photo: PV

1. Potato varieties:

Use potato varieties that are currently widely grown and have clear origins.

Seed tuber standards: Even tubers, free from pests and diseases, tuber skin is still tight; tuber size from 25-40 tubers/kg (tube diameter from over 25 to 45mm) with 2-3 sprouts 0.2-2cm long. Large seed tubers with many sprouts, 1-2 days before planting, should use a sharp knife to cut into pieces so that each piece has 2 sprouts and dip the cut surface of the seed potato into a mixture of dry cement powder + 30% lime powder or wood ash. Note, need to dip the knife in strong soapy water after each time cutting the tuber.

Seed quantity: 1,100-1,600 kg/ha depending on the size of the variety. Equivalent to 40-58 kg/sao in the North, 55-80 kg/sao in the Central.

2. Soil, soil preparation and bed making

Soil: This plant is grown on all types of well-drained soil such as fields that rotate with two rice crops, taking advantage of the water receding after floods or single-crop rice fields. Most suitable for light loam, sandy loam, porous, rich in organic matter, and proactive irrigation.

Making beds: Drain the rice fields 7-10 days before harvesting.

With dry and moist soil: After harvesting the rice crop, the field is cut close to the stubble, the straw is collected neatly into a pile in the corner of the field. When it is time to plant potatoes, plow 2 lines (going and returning) to create furrows, following the slope of the field, the furrow surface is 1.2m wide, 25-20cm high, the furrow is 30cm wide and plows a line around the field to facilitate irrigation and drainage.

On heavy, wet soil: The steps for making beds are the same as for moist soil, but note to make the furrows 25-30 cm deeper and plow a line around the field to create deep furrows to facilitate irrigation and drainage later.

3. Fertilizer:

Use fertilizer properly (4 rights); apply the right amount, type and balance of nitrogen, phosphate and potassium fertilizers; apply fertilizer correctly and at the right time as the potato plant needs it.

Fertilizer amount and time:

Lime powder: 0.5-0.6 tons/ha, 100% basal fertilizer, applied before planting.

Compost: 15-20 tons/ha, 100% basal fertilizer, applied before planting.

Phosphate fertilizer 0.5-0.6 tons/ha, 100% basal fertilizer, applied before planting.

Urea: 220-280 tons/ha, basal fertilization: 20% before planting, first fertilization: 40% when the plant is 15-20 cm tall (20 days after planting), second fertilization: 40% 8-10 days after the first fertilization.

Potassium: 220-280 tons/ha, basal fertilization: 20% before planting, first fertilization: 50% when the tree is 15-20cm tall, second fertilization: 50% 8-10 days after the first fertilization.

How to fertilize:

Basal fertilization: Mix all the compost, phosphate fertilizer, lime and 20% of the nitrogen fertilizer in each hole or furrow, then cover with a thin layer of soil.

Top dressing: Make a ditch and apply fertilizer under the straw layer between two potato clumps (avoid applying directly to the base of the plant), combined with watering to ensure adequate moisture.

4. Planting techniques:

Planting density and distance: Plant 2 rows/bed, 30cm from edge of bed, 60cm between rows and 25x30cm between tubers (about 1,440-1,800 holes/sao depending on potato variety, equivalent to 40,000-50,000 holes/ha).

How to grow:

Mix all the compost, phosphate fertilizer, lime and 20% of the nitrogen fertilizer in each hole or trench, then fill with a thin layer of soil and place the tubers alternately, with the potato sprouts facing up. Use crushed trench soil to cover the tubers with a thin layer; use straw to cover the entire bed surface about 7-10cm thick (1 sao of potato needs 3-4 sao of straw or stubble). Immediately after planting, water the bed evenly. If the soil is still very moist, there is no need to water, just use the soil in the trench to cover the straw so that the straw does not fly away.

If the soil is still wet, cover it with a layer of powdered soil and place the potato seed on top. Mix all the compost, phosphate, lime and nitrogen and apply around the potato seed. Cover the seed with a layer of powdered soil, humus, and rice husks; cover the entire bed with straw about 7-10cm thick.

5. Care techniques:

When the plant grows 7-10cm high, monitor it with normal care and add more straw so that all the fertilizer and seeds are not exposed to light.

Fertilization and care:

- Top dressing: Make a ditch and apply fertilizer under the straw layer between two potato clumps (avoid applying directly to the base of the plant), combined with watering to ensure adequate moisture. The first time, when the plant grows 15-20cm (20 days after planting), apply 40% of Urea and 40% of potassium; The second time, 8-10 days after the first time, apply 40% of Urea and 40% of potassium.

- Take care of:

+ After the plant grows about 7-10cm, prune the buds, keeping only 2-3 healthy buds on each plant.

+ Regularly check and add straw, especially during the stage when the plant shoots to form tubers (30 days after planting), avoid direct exposure of tubers to light.

+ Monitor growth and the situation of pests, diseases and weeds to have timely treatment measures.

Watering: Monitor regularly and add water when the soil is not moist enough. However, potatoes need moisture but do not like high humidity.

- If the soil is dry, water the furrows to 1/3-2/3 of the bed height so that the water can seep into the soil. When the bed surface turns dark, drain the water. If this is not possible, you can alternate between watering the furrows and moisten them with a watering can.

- Furrow irrigation should be completed 10 days before harvest.

6. Pest control:

Preventing armyworms: When the potatoes grow evenly, make sweet and sour bait and plant it in the field to kill adult armyworms; plant 150 baits/ha. Plant the bait continuously in the field. If the bait dries, add more bait solution.

Leaf miner fly control: Apply integrated pest management measures (IPM) such as field sanitation, limiting hosts around the field, using yellow traps, cutting and destroying heavily infected leaves, and spraying insecticides;

Late blight prevention: Regularly monitor the fields, especially potatoes 50 days after planting. If late blight spots appear on the leaves and the weather is favorable, spray with specific pesticides to prevent late blight.
Bacterial wilt control: Rotate with potatoes in the same field at least every 2.5-3 years. Rotate with carrots at least 3 times. Use disease-free seed tubers.

7. Harvesting and preservation:

Harvest:

+ After 50-80% of the leaves have turned yellow, you can harvest the potato. Choose dry weather to avoid the potatoes getting wet, making it difficult to preserve for a long time. Prepare 2 trays, go to the straw and straw and pick up the potatoes.

+ Sort tubers in the field when harvesting, small ones to use as seeds for the next crop.

Note: Separate potatoes from diseased potato clumps for commercial use, do not keep them for seed in the next crop.

Preserve:

- Commercial potatoes are kept in a dark place, avoiding light that causes the potatoes to turn green.

- Potatoes for seed need to be classified according to tuber size, put in mesh bags and stored in cold storage.

Nguyen Tuan Loc (Plant Protection Center of Region 4)