What are the precautions for raising sweet potato seedlings in early spring
Raising sweet potato seedlings in early spring is the primary step in sweet potato production, because problems caused by seedling quality are relatively common and seriously affect the subsequent growth and yield of sweet potatoes. Therefore, sweet potato seedling raising should be done well. Let's take a look at the precautions for raising sweet potato seedlings in early spring.
1. Build the seedbed
Before raising sweet potato seedlings, a greenhouse should be built early to promote a rise in ground temperature, and the seedbed should be built on a new plot where sweet potatoes have not been planted (or raised as seedlings). If it is a fixed seedbed, use new soil or substrate free of pests and diseases, and use fungicides and insecticides to thoroughly disinfect the seedbed to prevent damage from nematode disease, black spot disease, black mole disease, and so on.
2. Sow and raise seedlings at the right time
Before sowing and raising seedlings, first select high-efficiency varieties; when introducing varieties, also take local environment and climate into consideration to avoid losses. Sweet potato planting time is from early March to mid-April, and it takes about 35 days from sowing to cutting seedlings. Recently the temperature is relatively low, so it is even more necessary to prevent damage from late spring cold; when sowing sweet potatoes, choose sunny days with higher temperatures to prevent freezing. After sowing, if there is cooling weather, do not water; you can add one or two layers of small arched sheds to increase the seedbed temperature and prevent seedbed rot.
3. Choose virus-free seed potatoes
Sweet potatoes that had viral diseases such as leaf curl during last year's propagation must not be used as seed potatoes; virus-free seed potatoes should be selected to prevent leaf curl disease and viral disease and ensure yield and quality. The seed potatoes used for seedling raising should have the characteristics of the variety, be free of pests and diseases and wounds, not have suffered freezing damage, waterlogging damage, or mechanical damage, and be moderate in tuber size. Seed potatoes can be disinfected by soaking in warm water or with chemical agents, and can also be centrally sprouted at high temperature; after the tubers sprout, sow them, and after sowing, spread phoxim to control sweet potato stem nematode disease.
4. Strengthen seedling-stage management
The low-temperature growth temperature for sweet potatoes is 16 degrees, the suitable growth temperature is between 25-35 degrees, and the humidity is about 80%. When the sweet potato seedlings grow to 25 cm, lower the temperature to about 20 degrees and harden the seedlings for 2-3 days. Leave stubble of about 3 cm and use high cutting of seedlings; do not pull seedlings. Then use clean soil, add rooting agent, fungicide, and insecticide, add water, and mix into a milky mud slurry; dip the base of the sweet potato seedlings in the mud slurry, which helps rooting and seedling recovery and prevents pests and diseases.
The above is an introduction to the precautions for raising sweet potato seedlings in early spring. I hope it can help you. To learn more related knowledge, please follow us.