symptom
The diseased plant is mosaic or the heart leaf is shrunk, the old leaves die and fall off early, or the plant curls into a ball. Symptoms in the field often vary due to different sources of poison. Cucumber mosaic virus infection manifests as small, deformed or shrunken leaves. Infected by turnip mosaic virus, the leaves form dark and light mottled, and the leaf margins roll up. Infected by beet mosaic virus, the bright veins and new leaves turn yellow, or mottle, and the leaf edges curl downward.
Pathogen Cucumber mosaic virus (CMV), turnip mosaic virus (TuMV) or beet mosaic virus (BtMV) infection alone or combined. Beet mosaic virus belongs to the Potatoviridae Potatovirus genus, the mitochondria are linear, the size is 730nm×12nm, and it produces granular nuclear inclusions. The dilution limit is 1000 times, the in vitro survival period is 24-48 hours, and the lethal temperature is 55-60°C. Mainly by the peach aphid and soybean aphid or sap contact transmission.
Transmission routes and disease conditions
The virus overwinters on spinach and vegetable field weeds. Spread by peach aphid, radish aphid, soybean aphid, cotton aphid, etc. In the field, cucumber mosaic virus and turnip mosaic virus often mix and cause damage, forming corresponding symptoms. In spring or autumn drought years, root stubble or windbreak spinach is sown early, nest windy or close to radish and cucumber, and the disease is severe.
Prevention method
① Spread and hang silver-gray film strips in the field to avoid aphids.
②Clean the field in time, eradicate weeds in the field, and completely pull out diseased plants.
③Choose well-ventilated plots away from radishes and cucumbers for planting. Do sowing at the right time to avoid premature. In case of spring drought or autumn drought, water more to reduce disease.
④Apply sufficient organic active fertilizer or decomposed organic fertilizer, and increase phosphorus and potassium fertilizers to enhance the host's disease resistance.
⑤ Promote the use of insect-proof nets to prevent and control poisonous aphids, especially before winter.
⑥In the early stage of the onset, spray 100 times of the virus disease purifying agent Lvdikang (anti-virus type) or 900 times of 30% morpholine guanidine hydrochloride soluble powder or 500 times of 2% Ningnanmycin water or 300 times of 0.5% lentinan water Double liquid, once every 10 days, continuous control 2 to 3 times.
