Control of snake melon mosaic virus disease

Snake melon annual climbing vines; stems slender, much branched, longitudinally angled and grooved, pubescent and sparsely villous hirsute. Snake melon has well-developed roots, many lateral roots, adventitious roots, slender stems up to 5-8 meters long, five-angled and green stems, strong branching ability, green leaves, palmately parted leaves, round cracks, fine tomentose leaves, white Corolla, unisexual flowers, both male and female flowers, mostly racemes of male flowers, turquoise buds, light yellowish green when they bloom, and the occurrence of male flowers is earlier than that of female flowers. In general, female flowers begin to grow at 20-25 nodes of the main vine, and then both the main vine and lateral vines can produce female flowers continuously.

What is mosaic virus?

Mosaic virus is a virus transmitted by aphids that is parasitic on plants. Mosaic virus disease and gangrene (ringspot) mosaic disease usually occur as complications on the same plant, the damage is very serious. Mosaic virus disease, initially characterized by partial or overall wilting of leaves, showing yellow-white mottled mosaic-like, wrinkling. The infected and diseased plants at the early stage of growth had poor growth, no heading and heavy losses. Gangrene (ringspot) mosaic, forming many dark brown water clear spots or wheel spots of 1~3mm between leaf veins, purplish brown necrotic spots on veins and petioles. This symptom also occurs inside the leaf bulb. Some plants have disease spots on one side, resulting in distortion of the leaf ball; others are infected in the late growth stage, and disease spots are formed only in the leaves inside the leaf ball.

Mosaic virus disease is transmitted by aphids. Aphids carry the virus after sucking the sap of diseased plants and transmit the virus when they absorb the sap of other plants. When the virus-carrying aphids were isolated from plants for 3 hours, the virus was passivated and lost its ability to spread. Aphids are divided into winged type and wingless type, both of which live all year round. Winged type is active frequently from May to June and August, and then the reproduction of wingless type also increases. Therefore, in the early growth stage of cabbage sown in August, many winged aphids come from other cruciferous plants, among which poisonous aphids can cause mosaic disease. When the environmental conditions are suitable, the disease is very rapid. The pathogenic virus is attached to the roots of perennial cruciferous plants such as Horse thorn, turnip diseased plants and Indian welding vegetables for seed collection.

Snake melon mosaic virus disease:

Symptoms: the disease was seen in both seedling stage and adult stage. The top leaves of the diseased plants produce uneven small mosaic, seriously accompanied by slight scar mosaic, and the diseased leaves become smaller and slightly deformed. The diseased plants bear few melons, the flower spots appear slightly near the fruit stalk, and the diseased melons are twisted. It occurs from June to August, which is more common. The rate of diseased plants is 30%, 40%, serious as high as 80%.

Pathogen: can be caused by a variety of viruses, but mainly cucumber mosaic virus, is a virus.

Prevention and treatment: 7.5% morpholine guanidine (Keduiling) water agent 500 times solution or 3.85% ribavirin (virokang) soluble powder 800 times solution, 1.5% triacontanol sulfate copper dodecyl sulfate sodium (plant disease ling) emulsion 800 times, 24% mixed fatty acid copper (poison) water emulsion 800 times.