Prevention of Ring Rot of Potato

Potato ring rot is a common disease, but because the symptoms of diseased seed potato, especially the external symptoms are not obvious, seed cutting and storage are prone to infection. Four kinds of conditions are often caused in production: rotten seeds in the process of ① budding. ② did not emerge after sowing. ③ died after emergence. ④ formed diseased plants, few tubers, small tubers and rotten seed potatoes (in sharp contrast with normal seed potatoes in good shape at the late growth stage). According to a survey of diseased fields in Zouping county, the yield was reduced by 30% to 80%.

The pathogen belongs to bacteria, which has a short survival time in the soil, mainly overwintering in potato lumps, and the route of transmission is seed potato with disease, so it gets twice the result with half the effort before sowing. Precautionary measures:

1. Strict management of seed potatoes (1) seed potatoes @ # @ 136 potato departments, harvesting and culling diseased potatoes during propagation and harvest; quarantine should be strengthened during transportation, and transplanting from disease areas is strictly prohibited. (2) after the tuber was harvested, the tubers were first spread out in a ventilated place for 2-3 weeks, and entered the cellar when the temperature was stable at 0 ℃. Before entering the cellar, the seed potatoes were strictly re-selected to get rid of diseased rotten potato, mechanical damage, insect injury, flooded and cold-injured potato tubers. (3) the place with good drainage from the wind and the sun should be selected during storage. Ensure ventilation and ventilation during storage, keep the temperature at 1: 3 ℃, and the relative humidity is about 90%. Check frequently and remove the diseased potatoes together with the surrounding potato pieces in time.

two。 Select disease-resistant varieties suitable for local planting, such as Luyin 1 (Holland 7), Zhengshu 4 and so on.

3. Sowing small whole potato has strong vitality and good disease resistance. at the same time, it can avoid cross-infection such as ring rot bacteria, poor section healing and the invasion of saprophytic bacteria. In production, it is advocated to give priority to the selection of small whole potatoes as seed potatoes.

4. The main purpose of the whole potato sprouting method is to avoid the contact between the section and the section for a long time. Strictly remove diseased potatoes before sprouting; prepare as many knives as possible before cutting, and disinfect them with alcohol or flame first; observe the section when cutting potatoes, and find that when the vascular bundles turn milky yellow to dark brown, first remove the diseased potatoes, and then change the cutter. Soak the cutter in 50 mg / L copper sulfate solution for more than 10 minutes.

5. Plant ash mixed with seed and sprinkled with a layer of plant ash, not only keep the section dry, control bacteria, but also increase the application of potassium fertilizer, which is conducive to drought and cold resistance.

6. Apply 50 mg / kg cupric sulfate poisonous soil to each hole and spread it evenly around.

7. Formula fertilization, ridge cultivation and organic fertilizer, nitrogen, phosphorus and potassium about 2.5 ∶ 7 ∶ 4.5 ratio, phosphate fertilizer application of calcium superphosphate to supplement calcium, ridging planting to enhance plant disease resistance.