Long scab on the epidermis affects the sales phase how to prevent and cure potato scab

Potato scab means that the potato skin is covered with scars of different sizes and depths. After the occurrence of scab, although the spot is limited to the potato cortex, but the diseased potato is not resistant to storage and its appearance is ugly. The quality of susceptible potato is poor and the commodity value is low.

Potato scab

The causes of scab: first, the seed potato was sown without soaking and disinfection; second, it failed to avoid continuous cropping with potatoes, radishes, carrots, sugar beets and other crops that had occurred scab; third, the expansion period of potato pieces was in a period of high temperature and drought.

Prevention and control measures:

First of all, disease-resistant varieties were selected, such as Yushu No. 1, Luyin No. 1, Yushu No. 1, Chunshu No. 1, Taishan No. 1, Baifeng, Wulibai and so on.

Secondly, crop rotation should be carried out. First, the field where scab has occurred has been rotated for more than 2 years; the second is to improve the water conservancy facilities in Datian to ensure that there is sufficient water during the tuber-forming period and to keep the field moist; the third is to plant and select acidic soil.

Third, apply organic fertilizer. For the field of residual bacteria, insisting on the application of organic fertilizer and bio-organic fertilizer can better inhibit soil-borne bacteria.

Fourth, chemical prevention and control. ① can soak washed potato seeds in 0.2% formalin (formaldehyde) solution for 2 hours, or soak them in 0.1% hydroquinone (chemically pure) aqueous solution for half an hour, then take them out to dry and sow seeds. ② can disinfect the soil with 40% pentachloronitrobenzene powder in diseased fields with 1.2-2 jin per mu. In the early stage of ③, 65% mancozeb wettable powder was sprayed with 1000 times, every 7-10 days, a total of 2-3 times.