Tomato virus diseases have been common in recent years. There are three common types: mosaic disease, stripe disease and fern leaf disease. They often occur in combination, among which mosaic disease is the most common. For plants infected with mosaic disease, the diseased leaves show dark green or light green mosaic spots, the leaf surface is wrinkled and uneven, and the young leaves are often deformed and twisted. Vegetable plants with early onset can't stretch at the top. The whole plant is dwarfed. Vegetable plants with late onset only show mosaic leaves on the heart leaves, no symptoms on old leaves, and the vegetable plants are not dwarfed. Mosaic disease is caused by tobacco mosaic virus. The virus can survive for a long time in the residual body of infected plants, and can also stick to the surface of seeds or penetrate into the seed coat, causing the disease in the second year. The virus is mainly transmitted by contact friction and aphids.
Toamtos Yellows Leaf Curl Virus
Tomato Aphids
Prevention methods:
① Select disease-resistant varieties, such as Nongbo Fenba No. 3, Nongbo Fenba No. 15, Hongza 18 tomato, Xiafen, Dongnong 713, Zhongshu No. 5, Zhongza 105, Yukang No. 4, etc.
② Select disease-free seeds and seed treatments. Leave the seeds from disease-free vegetable plants, soak the seeds in 300 times of formalin for 2 hours, then soak in 100 times of potassium permanganate for 30 minutes, take them out and wash them with clean water before sowing.
③ Cultivate strong seedlings, plant early, harvest early, avoid the peak of the disease, and reduce the disease.
④ Control aphids, thoroughly control aphids from the seedling stage, protect seedlings, and reduce disease transmission. For each mu, 10-15 grams of pirimicarb can be mixed with 50-60 kilograms of water or sprayed with 1000-2000 times of 40% dimethoate. The liquid medicine is sprayed on the back of the leaves and the tender parts of the vegetable plants.
⑤ Strengthen cultivation management. In field operations such as transplanting, pruning, and fruit harvesting, the healthy plants should be treated first, and then the diseased plants should be treated to avoid contact infection.
⑥ chemical control;
a. Pay attention to early pest control and disease prevention, use 6000 times liquid of 21% kill-killing EC; 4000-5000 times liquid of 10% anthracloprid WP, or 3000-4000 times liquid of 2.5% Kung Fu EC, or 20% quick kill 2500 times of butyl EC to control aphids.
b. Prevention can be sprayed with 300 times of antiviral agent No. 1 or 100 times of NS-83 Pit Enhancer.
c. In the early stage of the disease, 20% virus A, or 20% virus nemesis, or 20% virus Ning can be wetted powder 400-500 times; or 5% bacterial poison clear water agent 500 times, or 1.5 phytopathogen emulsion 1000 times Spray control. 1 time every 7 days, 2 to 3 times in a row.
Expert Tip: Viral diseases are also serious on peppers, and eggplants are lighter. Once vegetables are infected with viral diseases, it is difficult to cure. Only by improving the disease resistance of plants can the impact of viral diseases on yield be reduced.
