Identification and control of rapeseed virus disease

Oatmeal, also known as naked oats, is also called bitter thistle in some places, belonging to chrysanthemum fodder. It is a pointed leaf lettuce with young shoots and tender leaves as its products. Its leaves are long lanceolate, light green in color, crisp and tender in texture. It has a very fresh, fragrant taste and has a unique flavor. It contains a lot of vitamins and a lot of calcium, iron, protein, fat, vitamin A, vitamin B1, vitamin B2 and other nutrients. It is the top grade of raw vegetables. It is known as "Phoenix tail".

Morphological characteristics of Brassica napus

Rape belongs to Compositae, which is a pointed leaf lettuce with tender shoots and leaves as its products. the leaves are long lanceolate, its appearance is a bit like the "head" of lettuce, the leaves are slender and spreading, and the bamboo shoots are thin and short. From the perspective of blood relationship, rapeseed belongs to a variety of leaf lettuce-long-leaf lettuce, which is similar to the familiar lettuce, so it is also known as Niu Li lettuce. Its color is light green and its growth is strong. Disease resistance, strong adaptability, crisp and tender texture, taste extremely fresh and tender, fragrant, known as "Phoenix tail".

Identification and control of rapeseed virus disease

Symptoms of rape virus disease:

The disease can occur in the whole growth period, and the early onset has a great influence on the yield. Infection at seedling stage: the disease appears immediately after growing a few true leaves, with light green and dark green flowers and leaves mottled on the leaves. Sometimes the veins are clear and the leaves are wrinkled and twisted. The adult plant was infected with disease, the diseased plant was obviously dwarfed, and the leaves were irregularly twisted.

The pathogen of rape virus disease:

Lettuce mosalcvirus (LMV), called lettuce mosaic virus, Cu-cumbermosaicvirus (CMV), cucumber mosaic virus, lettuce mosaic virus belongs to potato Y virus family, potato Y virus genus, granule linear, long 750nm, dilution limit 10 times 100 times, in vitro virus preservation period 2-3 days, detoxification temperature 55-60 ℃, can be transmitted by juice contact or aphids.

Transmission routes and conditions of rapeseed virus disease:

The source of the poison comes from lettuce, lettuce and spinach from nearby vegetable fields. Seeds can also be poisonous, and disease can be seen immediately after emergence. It is mainly transmitted by aphids in the field, and the sap of diseased plants is also transmitted when they come into contact with friction. The transmission rate of peach aphid is the highest, and turnip aphid, melon aphid and Euphorbia longissima aphid can also transmit virus. The occurrence of the 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 of rape virus disease:

(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 proper shading on plastic film.

(3) watering small water frequently after emergence, squatting seedlings properly, and timely prevention and control of aphids.

(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.