How to prevent the rotten cellar of sweet potato

The biggest problem of sweet potato during storage is rotten cellar. Once the cellar is rotten, light will reduce the quality of sweet potato, heavy will lead to the whole cellar sweet potato rotten, resulting in varying degrees of loss. The rotten cellar of sweet potato is mostly caused by physiological diseases and infectious diseases. Physiological diseases mainly occur when the temperature is not suitable. If the pit temperature is lower than 10 ℃ for a long time, it is easy to cause chilling injury and cause cellar rot. If the pit temperature is higher than 20 ℃ for a long time, it is beneficial to the infection of weak parasites and the spread of black spot, resulting in rotten cellar. Infectious diseases can be divided into two categories: one is diseases that have occurred in the field and continue to spread during storage, such as black spot and stem residue, etc., and the other is diseases that occur after storage, such as soft rot, penicillium and so on.

The following technical measures should be taken to prevent the rotten cellar of sweet potato:

First, build the cellar cautiously. The potato cellar should be built in a place where the soil is strong and dry. The potato cellar is required to be moisturized, ventilated, convenient for inspection and management, and not easy to collapse. 1.5% formalin should be sprayed to disinfect the old cellar before use. The premise of potato harvest is required to build a cellar as soon as possible.

Second, harvest at the right time. In order to avoid frost injury and cold injury, harvest should be made on a sunny day before light frost. Cut the vine on the same day, plane the potato on the same day, air in the sun on the same day, and enter the cellar on the same day. In the process of harvest, you need to be light and light in order to reduce the trauma of potato chips.

Third, select before storage. Choose carefully before entering the cellar and thoroughly get rid of sick, damaged and moldy potatoes. The storage capacity should be 2 to 3% of the cellar capacity. Cellar sweet potato does not keep warm, cellar sweet potato has high temperature and humidity, and is prone to soft rot.

Fourth, temperature regulation management. At the initial stage of entering the cellar, keep the pit temperature about 20 ℃, pay attention to ventilation. After a week, the pit temperature was maintained at 12 ℃ ~ 15 ℃, which was the most suitable temperature for sweet potato storage. With the decrease of air temperature, the mouth of the pit should be closed at the right time, and the cover should be added to make the lowest temperature of the pit not lower than 10 ℃. Set a small hole in the cellar and insert a thermometer to observe the pit temperature at any time. With the increase of air temperature in early spring, the mulch should be reduced in time, and the ventilation pipe should be gradually increased to avoid too high or too low pit temperature.