Prevention and treatment of six common diseases of tomato

Several diseases often occur in tomato, such as fruit cracking, early blight, late blight and so on. Today. The editor of Green Food Network introduces vegetable farmers to the symptoms and prevention of six common diseases of tomato.

Dehiscent tomato

Tomato split fruit. From the expansion to the green ripening stage, the pericarp of tomato began to crack radially, which was small at first and deepened before coloring. There are also annular cracks in the center of tomato pedicel. The imbalance of water is the main cause of fruit cracking in tomato, and the varieties are also related. The measures that can be taken to prevent tomato cracking are as follows: one is to select tomato varieties with crack resistance, luxuriant branches and leaves, thick and tough pericarp. The second is to maintain the suitable dry humidity of the planting soil. The third is to increase the application of organic fertilizer, improve soil structure, and improve the ability of planting soil to conserve water and fertilizer. Fourth, properly pick the branches and hearts of the tomatoes to ensure that the branches and leaves of the tomatoes are luxuriant, so that the excess water can be transpirated and prevent the tomatoes from being exposed to bright light. Fifth, timely harvest.

Early blight tomato

Tomato early blight. After the disease, there are concentric wheel-like disease spots on tomato leaves, dark brown, strong water stains, stems and petioles, fruits and so on. Concentric wheel-like disease spots appear when the air humidity is high. The tomato can be sprayed with 70% mancozeb wettable powder diluted 500 times or 75% chlorothalonil wettable powder diluted 400 times before and after the attack, once every 7 days, 3-4 times in a row.

Leaf mildew tomato

Tomato leaf mold. There are sunken and hard black disease spots around the stalk of the diseased tomato, and the tomato leaves have irregular yellow disease spots. When the humidity is high, it produces a brown mildew layer, which makes the leaves withered and yellow, curl, and then fall off. After the onset of the disease, the tomato can be sprayed with 70% mancozeb wettable powder diluted 500 times or 80-1000 times diluted with 50% Sukelin wettable powder, once every 7 days, 3-4 times in a row.

Grey mold tomato

Tomato Botrytis cinerea. The disease of green tomato is usually more serious. Botrytis cinerea first infects the residual stigma or petals, and then extends to the tomato or stalk, causing the pericarp of the tomato to become grayish white, accompanied by a gray thick water-rotten mildew layer. During flowering, 0.1% of 50% Sukeling wettable powder or 50% virus A WP diluted 500 times, or 800 times diluted ribavirin diluted diluted, can be added to the flowering liquid to spray tomatoes, once every 7 days, 2-3 times in succession.

Late blight tomato

Tomato late blight. The petiole and main stem of tomato are dark brown and rotten, the seedlings wilt and lodge, the leaf tip is the beginning of the disease spot, when the humidity is high, there is white mildew, when dry, the brown spot turns dark brown, watery or moire, slightly sunken, the diseased fruit is hard. During the onset of the disease, the tomato can be sprayed with the dilution of 40% of the wettable powder diluted 300-400 times, once every 7 days. The dust method can also be used to control late blight, that is, a powder sprayer is used to spray 1 kg of 5% chlorothalonil compound powder per mu and sprayed in the evening.

Navel rot tomato

Tomato navel rot. The navel of tomato has a water-immersed spot, which gradually expands, resulting in the top of the tomato sunken and browning; the spot is usually 1--2cm in diameter and extends to a small half of the tomato in severe cases. In the dry part of the leathery disease, encountered wet conditions, the surface produced a variety of white, pink and black mildew layer. During the onset of the disease, 0.1% calcium nitrate, British calcium or 1% superphosphate can be applied to the root, once every 10 days, 2-3 times in a row.