How to manage potatoes during the seedling stage? These key points are crucial
When potatoes are at the seedling stage, management is crucial. The main measures are:
1. Timely hilling to preserve full stands. Most of the soil in potato fields is yellow loam, with large soil particles, poor water-holding capacity, and rapid soil moisture evaporation. At present, because the dry soil layer is 10-15 cm, while the potato seed tubers are about 10 cm in size, the seedlings will be affected by drought after emergence. For such seedlings, shallow intertillage and hilling should be carried out in time during the emergence period to thicken the covering soil layer, cut off soil capillaries, slow the rate of water evaporation, extend the survival time of the seedlings, and do everything possible to preserve a full stand. The timing of covering with soil should be when 30% of the young sprouts are pushing through the soil.
2. Timely fertilization to promote strong seedlings. In high-altitude areas there is some night-tide soil, mainly loam type, with small soil particles and strong soil water-holding capacity; the current soil moisture conditions are relatively good. For such fields, after emergence, about 10 kg of urea per mu should be applied as a topdressing to quickly promote seedling growth and maintain strong seedlings. The fertilization method is to broadcast it between the seedlings, then carry out intertillage and hilling.
3. Foliar spraying of antitranspirants. After the potato leaves have fully expanded, antitranspirants can be used for foliar spraying. Antitranspirants can form a protective film on the leaf surface to slow water evaporation. For antitranspirants, sodium bisulfite, humic acid, calcium chloride, fulvic acid (FA), triadimefon, crown ether, etc. can be selected, and they should be used according to the product instructions.
4. Check seedlings and replant. For plots with more than 30% missing seedlings, crops such as early-maturing corn and kidney beans can be spot-planted, and through local intercropping and relay intercropping, the field's utilization efficiency can be improved, losses reduced, and income increased. If effective rainfall occurs soon after emergence, side branches can also be broken off from the base of normal potato plants during rainy days and used for cuttings, in order to reduce missing seedlings.
5. Control of underground pests. After potato sowing and during the seedling stage, potatoes are prone to damage by underground pests, causing seed rot and missing seedlings. Therefore, a plan for controlling underground pests should be formulated. The main underground pest is the cutworm. For cutworms below the 3rd instar, spray 40% phoxim at 800 times dilution or 2.5% deltamethrin emulsifiable concentrate at 2000 times dilution.