Control methods of dwarf rape virus disease caused by leaf wrinkling and twisting disease

Rapeseed virus disease can occur in the whole growth period, the disease occurs early, and has a great effect on the yield. Infection at seedling stage: the disease appears after several true leaves are grown, and the leaves are mottled with light green and dark green. Sometimes the veins are clear and the leaves are wrinkled and twisted. The adult plant is infected with disease, the diseased plant is dwarfed, and the leaf is irregularly twisted. The main pathogens of rape virus disease are lettuce mosaic virus and cucumber mosaic virus, which are transmitted by juice contact or aphids.

Rape virus disease

The virus source of rape virus disease comes from lettuce, lettuce, spinach and so on. Seeds can also be poisonous, and disease can be seen immediately after emergence. The transmission in the field mainly depends on aphids, and the sap is also transmitted when the diseased and healthy plants come into contact with friction. The transmission rate of peach aphid was the highest, while that of radish aphid, melon aphid and Euphorbia longissima aphid was low. The occurrence of rape virus disease is related to the spread and weather, high temperature and drought, aphids suffer heavily. Generally, the average temperature is higher than 18 ℃, the field is short of water, and the disease spreads rapidly.

Prevention and control methods:

(1) selecting disease-resistant varieties.

(2) when planting in summer and autumn, the disease can be reduced by using anti-insect net or sunshade net or plastic film.

(3) after emergence, watering the seedlings with small water frequently, squatting seedlings properly, finding aphids and controlling them in time.

(4) spraying 500 times of 2% Ningnanmycin water or 800 times of 24% mixed fatty acid alkali copper water emulsion at the initial stage of the disease.