Causes and control methods of tomato early blight

Tomato early blight is one of the common diseases, the initial damage is the leaves, and then to the branches and fruits, the symptoms of the disease are a circle of threads, also called ring disease, it has a great impact on tomatoes, seriously affecting its quality and yield, so what causes the disease? And how to prevent it?

1. Causes of tomato early blight

Early blight usually occurs between late May and early June, when the air is warm and humid is high. It spreads through air, wind, rain, etc., and can spread not only to other healthy tomatoes, but also to crops such as eggplants, peppers, and potatoes. In addition to being harmful to tomato leaves, stems and fruits, it will overwinter with air, rain and wind falling into the soil, and once it is infected, it is difficult to control.

2. Prevention and control methods of tomato early blight

1. Variety selection

Early blight mostly occurs in tomato varieties with large seedlings and large leaves, so early maturing and narrow-leaved varieties with mild incidence of early blight can be selected. Before planting, tomato seeds can also be soaked in warm water at about 50 degrees to kill early blight germs.

2. Pay attention to crop rotation

The pathogen of early blight has an incubation period of more than one year, and solanaceous crops such as peppers, eggplants, and potatoes will also be infected with early blight, so try to carry out reasonable rotation with non-solanaceae crops for more than 2-3 years to reduce the possibility of early blight.

3. Combination of prevention and control

Pesticide control should be started when tomato seedlings are planted, and the seedlings can be thoroughly sprayed with Bordeaux solution before planting, and then sprayed with pesticides 40% chlorothalonil suspension for a second time after 7-10 days of planting. In the high incidence period of early blight, spray pesticides in time. After the early blight is discovered, it is necessary to spray fungicides in time according to the weather conditions to control the spread of the disease.

4. Control the air humidity

High air humidity is the main reason for the occurrence of early blight, which may occur in the entire stage of tomato planting, so the humidity of tomatoes planted in greenhouses must be controlled between 40%-55% to prevent the outbreak of early blight due to too much air humidity.

The above is the introduction of tomato early blight, which has a serious impact on the yield and quality of tomatoes, and growers should take good control measures!