Key Points of High-Yield Cultivation Techniques for Potatoes Planted After Tobacco
I. Land selection. The growing period of potatoes planted after tobacco is roughly from July to December. Throughout the entire growing period, a certain amount of water, fertilizer, light and temperature are needed. For this reason, it is better to choose tobacco fields at an altitude below 1400 m with loose sandy loam or red loam soil and medium fertility for planting.
II. Good seed. For good seed, select early- and mid-maturing virus-free varieties with high yield and good quality, such as Hezuo 88, Lishu No. 6, etc.
III. Fine land preparation and sufficient basal fertilizer. Fine land preparation and scientific fertilization are the key to creating high yields in potatoes planted after tobacco. When the tobacco leaves in the field are harvested up to the middle and upper parts, loosen the soil in time, clear weeds and residues from the ridge surface, and dig planting holes between the two sides of the tobacco, with a hole depth of 30 cm. In the holes, apply 800 kg of high-quality farmyard manure, 30-40 kg of ordinary calcium superphosphate, and 40 kg of compound fertilizer per mu as basal fertilizer.
IV. Sowing. Generally, interplanting potatoes begins when the tobacco leaves are harvested up to the middle and upper parts, and planting from August 10 to August 20 is better. Ensure that the potatoes fully bloom in October.
V. Cultivation techniques
1. Sprouting and disinfection treatment. Soak the seed potatoes to promote sprouting, break dormancy, promote early emergence of seedlings, and achieve uniform and robust growth. Select 1 g of the original drug of 920 (gibberellin) and add 50 ml of strong alcohol to fully dissolve it, then add 100 kg of water, soak the seed potatoes for 10-15 minutes, remove them, and air-dry them before entering the sprouting stage. When the sprouts are 0.5-1 cm long, they can be sown.
2. Field management. ① Potatoes emerge 15-20 days after sowing. Check for and fill gaps in time to ensure uniform and robust seedlings. ② Fertilizer and water management. When the potato seedlings reach a height of 15 cm, apply 10-15 kg of urea per mu for the first topdressing. Water in time after topdressing to promote robust plant growth. When the potatoes enter the early budding stage, carry out the second topdressing, applying 15-20 kg of urea per mu by digging holes and applying deeply, keeping the soil moist to promote rapid tuber expansion and growth, thereby obtaining a high yield. ③ Intertillage and weeding. After the flue-cured tobacco harvest is completed, promptly remove the tobacco plants from the field, use a quick hoe with shallow shoveling so as not to damage the potato plants, and combine intertillage with hilling to loosen the soil and improve aeration, maintaining suitable soil moisture.
VI. Pest and disease control.
1. Disease control. The main common diseases of potatoes planted after tobacco are late blight and bacterial wilt, etc. A high-efficiency, low-toxicity systemic fungicide such as 25% metalaxyl-mancozeb or Shadufan at 500-700 times dilution can be sprayed 2-3 times consecutively, once every 7-10 days, for control. Scientific fertilization can also reduce field humidity, improve plant disease resistance, and prevent the occurrence of potato diseases.
2. Insect pest control. During the growth of potatoes planted after tobacco, the temperature is gradually decreasing, so the main focus is on preventing underground pests. Chlorpyrifos at 2-3 kg/mu can be thoroughly mixed with farmyard manure and applied in holes at sowing, or phoxim emulsifiable concentrate at 1:500 dilution can be mixed with water and poured during fertilization at the seedling stage.
VII. Harvest.
Autumn cultivation has a short time and early maturity, so it should be harvested at the right time to improve product quality. When mature, it can be dug up, or harvesting should be completed before frost arrives, and it should be graded and packaged by large, medium, and small sizes for market or stored in a ventilated place.