Causes and Prevention of Potato decay during Storage

Potato is one of the main crops in Qinghai province, which has the characteristics of high and stable yield, short growth period, strong adaptability, rich nutrition, both grain and vegetable, and high economic utilization value, so it is deeply welcomed by the general public. In recent years, with the development of potato industry, significant production benefits have led to the expansion of potato planting area year by year. However, due to the extensive scientific management of potato during production, harvest, transportation and storage, a large number of seed potatoes rot during storage. According to the investigation in recent years, potatoes in most Naoshan areas of Qinghai Province have the problem of varying degrees of decay during storage, serious whole cellar decay, causing undue economic losses to farmers and dampening the enthusiasm of farmers to grow potatoes.

I. causes of potato decay during storage

1. Late blight infection in the field is one of the main causes of potato rot during storage. At present, potato varieties Gaoyuan No. 4 and Xiazhai 65 cultivated in Qinghai Province do not have strong resistance to late blight, coupled with continuous rain, lack of light, lack of heat and excessive humidity in the field in the past two years. Potatoes in some areas have been slightly infected with late blight in the field, and the symptoms of tubers are not obvious at harvest, so the infected potatoes are directly put into the cellar.

two。 In the process of harvest and transportation, there was no light handling, light handling and light transportation, resulting in a large number of tuber damage, and the damaged potatoes were not removed when entering the cellar, which provided favorable conditions for the invasion of bacteria.

3. There was a high humidity in the field during harvest, and the tubers adhered to a lot of soil, and they entered the cellar directly without drying and ventilation before entering the cellar.

4. After the potato entered the cellar, the temperature and humidity in the cellar were not controlled properly, and the storage quantity of potato was too large, which worsened the microclimate in the cellar, created conditions for the occurrence of late blight and dry rot, and led to a large number of potato rot.

II. Prevention and control measures

1. Virus-free and disease-resistant seed potatoes were selected. Local varieties with good yield and resistance to late blight, such as green vegetable No. 2, detoxification 175 and so on, were selected.

two。 Timely control of potato late blight. When the central diseased plant was removed in time in the field, 64% alum wettable powder 500x or 58% metalaxyl manganese zinc wettable powder 500x, 65% Deisen zinc wettable powder 500x, or 25% Ruidui wettable powder 1000 times were sprayed in the early stage of the disease, and then sprayed once every 7 to 10 days for 2 times in a row.

3. Prepare the processed products before entering the cellar:

Before ① enters the cellar, remove 3cm of the old soil from the cellar, dry it for more than a week, and disinfect it with 1% potassium permanganate or lime water.

② potatoes must be handled gently in the process of handling, and must not be poured directly into the pit.

Before entering the cellar, ③ tubers should be hung in the dry, ventilated and shaded place for a few days to strictly eliminate diseased, rotten and damaged potatoes and remove the attached soil.

4. For storage management:

In order to keep the pit temperature consistent with the internal temperature of the potato pile, the storage capacity must account for 1/2 of the cellar capacity, the height of the potato pile should be less than one meter, and the ventilation hole should be placed in the potato pile with wheat or rapeseed stalk, which should be about 30 cm higher than that of the potato pile.

② opened the pit door and vents at the initial stage of entering the cellar, and blocked the stomata when the temperature dropped to-1 ℃.

③ controls the humidity in the cellar. If it is found that water droplets are formed in the upper layer of the potato pile, water droplets appear in the pit wall, and the potato pieces are wet, it indicates that the humidity in the cellar is too high and should be ventilated through the pit door and vent.

With the increase of air temperature in spring, ④ opened the stomata or pit door to keep the pit door temperature at 1-4 ℃.