Detailed Explanation of High-Yield Cultivation Techniques for Spring-Planted Potatoes
Potatoes have the characteristics of being nutrient-rich, serving as both food and vegetable, high-yield and efficient, and having a short growth period. In recent years, with the adjustment of agricultural structure, the potato planting area has increased year by year. The main high-yield cultivation techniques are:
Selecting improved varieties. Our province belongs to the spring-autumn double-cropping potato region, so early-maturing varieties should be selected that tuberize early, have fast tuber expansion, a short dormancy period, high yield, good quality, and disease resistance, such as Yu Potato No. 1, Yu Potato No. 2, etc. These varieties are best as virus-free seed potatoes. Virus-free potato seedlings emerge early, have robust plants, large leaves, well-developed root systems, strong stress resistance, and great yield-increasing potential.
Plot selection. Select sandy loam or loam soil that is fertile, flat in terrain, convenient for irrigation and drainage, has a deep plow layer, and loose soil texture. The previous crop is best as cereal crops, legumes, cotton, radish, Chinese cabbage, etc. Solanaceous crops such as eggplant, pepper, tomato, and tobacco should not be used as the previous crop, in order to reduce the occurrence of diseases.
Fine land preparation. After the previous crop is harvested, deep plowing of about 30 cm should be carried out in time, so that the soil freezes and weathers, to receive rain and snow and freeze overwintering pests to death. After the early spring thaw, plowing and harrowing should be done early, so that the plow layer is fine and clod-free, and the field surface is level and free of stubble, preserving soil moisture for sowing.
Applying sufficient base fertilizer. Potatoes are a high-yield, fertilizer-loving crop, so sufficient base fertilizer should be applied in combination with early spring land preparation. Generally, per mu, apply 4000-5000 kg of high-quality decomposed organic fertilizer, 20 kg of urea, 50 kg of superphosphate, and 30-40 kg of potassium sulfate. Cutting seed potatoes and sprouting. For spring planting, about 120 kg of seed potatoes are needed per mu. One month before sowing, place the seed potatoes in a dark environment at 15°C-20°C for vernalization treatment. 20-25 days before sowing, cut the seed potatoes into pieces, each with 1-2 buds, weighing 25-30 g. After cutting the seed potatoes, rinse the starch on the cut surface with a 600-fold carbendazim suspension, then after drying, place them indoors at 15°C-18°C and use the sand-layer stratification method to promote sprouting. When the sprouts grow to about 2 cm, place them under scattered light to air and dry. After the sprouts turn green and thicken, they can be sown.
Sowing at the right time. The suitable sowing period for spring-planted potatoes in our province is late February to early March. If sown too early, the seedlings are prone to frost damage. If sown too late, the tuber expansion period will be in the high-temperature and rainy season, the aboveground stems and leaves are prone to excessive growth, affecting nutrient accumulation in the tubers and causing severe yield reduction, and the tubers are prone to disease infection and rotting, and are not suitable for storage.
Reasonable close planting. Use ridge cultivation with wide and narrow rows, with a ridge spacing of 1 m, ridge top width of 60 cm, and ridge height of 15 cm, with two rows per ridge, a wide row of 70 cm, a narrow row of 30 cm, and a plant spacing of 25-30 cm. Open furrows for sowing. After placing the potato pieces in the furrow with sprouts facing up, apply 2-3 kg of 3% phoxim granules per mu, mixed with 15-20 kg of fine soil, and spread evenly along the furrow to prevent underground pests. Then cover with soil to fill the furrow and press level. Apply 100 mL of 72% dual or 120 mL of 50% acetochlor per mu, mixed with 40-50 kg of water, and spray evenly to control weeds, then immediately cover with film.
Field management
1. Timely film breaking. 20-25 days after sowing, the seedlings will successively push against the film. On a sunny day, timely break holes in the plastic film to release the seedlings, and cover the holes with fine soil.
2. Intertillage and earthing up. In combination with topdressing and watering, earth up once each at the early bud stage and early flowering stage, to prevent tubers from being exposed above the ground.
3. Fertilizer and water management. According to soil moisture, water once each at the full seedling stage, bud stage, flowering stage, and rapid tuber expansion stage. In combination with watering and depending on seedling condition, apply 10-15 kg of urea per mu at the early flowering stage. Stop watering 5-7 days before harvest, to prevent tuber rotting in the field and affect tuber storage. In addition, in the middle and late stages of plant growth, spray 0.2%-0.3% potassium dihydrogen phosphate solution on the leaves twice, 40-50 kg each time per mu, to prevent premature aging.
4. Chemical control: At the bud and flowering stage, for fields showing a tendency to excessive growth, use 20-25 g of 15% paclobutrazol per mu, mixed with 40-50 kg of water, and spray to control excessive growth.
5. Disease and pest control. In the early stage of viral disease, spray with 500-fold 20% virus A wettable powder or 1000-fold 1.5% zhibingling emulsion. In the early stage of late blight, spray with 500-fold 64% sandofan wettable powder or 600-fold 25% ridomil, spraying once every 7 days for 3 consecutive sprays. To control aphids, use 2000-fold 10% imidacloprid wettable powder or 2000-3000-fold 50% pirimicarb wettable powder spray.
Timely harvest. Spring potatoes do not necessarily need to be harvested after maturity. The harvest should be based on market demand and carried out before the arrival of high temperatures and the rainy season. Harvest should be done on a sunny day when the soil is dry.