How to select and store sweet potato seed tubers? These methods you need to master

I. Timely harvest: If sweet potatoes are harvested too early, the yield is lower; if harvested too late, they are prone to frost damage, which affects storage. Therefore, it is generally best to begin harvesting when the temperature is around 18°C, and finish harvesting when the temperature is above 10°C (that is, before the frost-kill period).

II. Carefully select tubers: When harvesting and selecting good sweet potato varieties, you must dig and cut carefully to avoid wounds. In order to produce more sprouts, strong sprouts and lower costs, tubers weighing 150-200 g should be selected as seed. The selected tubers must be disease-free, free from flood damage, and also have the typical characteristics of the variety. At harvest, it is best to cut the vines in the morning, dig in the forenoon, and put them into the cellar in the afternoon.

III. Cellar storage: For storage in a large house cellar or a pit cellar, the old cellar must be strictly disinfected before the seed tubers are put in, for example by spraying the storage cellar with a 600-fold dilution of 50% carbendazim or a 500-fold dilution of 5% Ansosuojunqing liquid preparation. When storing sweet potatoes, each layer of sweet potatoes stored should be evenly sprayed once with a diluted solution of "sweet potato preservative." The special management measures for storing sweet potatoes in a large house cellar are introduced as follows: in the early storage period (15-20 days after being put into the cellar), heating should first be applied for 18-24 hours so that the temperature inside the cellar reaches 35°C-38°C, and this should be maintained for four days and nights. After that, open the skylight to release moisture and lower the temperature, and after 18-24 hours, bring the cellar temperature down to 15°C; in the middle storage period (from 20 days after being put into the cellar to early February of the following spring), the main tasks are heat preservation and temperature raising to prevent the seed tubers from cold damage, and the cellar temperature at this time should be kept stable at 12°C-13°C; in the late storage period (from early February to seedling raising), open the cellar in time to inspect and remove excess carbon dioxide. Sweet potatoes stored by the above methods have a long fresh-keeping time, and the intact rate of sweet potatoes reaches more than 96%.