Four key points for prevention and control of grape gray mold

Botrytis cinerea is one of the most common and serious diseases in grape production. Its pathogen has a wide range of parasitism, fast transmission and strong pathogenic ability. once inflorescence is infected, it can make flowers dry and fall off, resulting in huge yield loss. The following is to introduce to you the four main points of grape gray mold prevention and control.

First, clean up the shed environment and reduce the source of primary infection.

Remove stubble and withered branches and leaves in the shed before planting; remove diseased leaves, diseased flowers, diseased fruits, lower yellow leaves and old leaves in time. After removal, it is best to use plastic bags to seal them and take them to the outdoor deep burial or burn. Wash your hands after cleaning, and then carry out other plant management operations to avoid the spread of germs caused by human factors.

2. Strengthen the management of greenhouse facilities and plant cultivation

The main results are as follows: (1) improve cultivation techniques and strengthen field management. After grape planting, double-ridge film and under-film drip irrigation technology is adopted to reduce the humidity in the shed; watering is best carried out in the sunny morning, and watering is avoided in rainy days; when the noon temperature reaches 25 ℃ ~ 30 ℃, ventilation and humidity reduction, increase carbon dioxide, so that the humidity is reduced to about 70%.

(2) reasonable close planting according to specific conditions and morphological characteristics of varieties. The application of basic fertilizer based on rotten farm manure, increasing the application of phosphorus and potassium fertilizer, preventing the partial application of nitrogen fertilizer, making the plant too dense and overgrowing, affecting ventilation and light transmission, and reducing plant resistance.

Third, improve plant resistance and optimize plant flower and fruit management.

(1) to avoid direct pruning and forking operation after contact with diseased leaves or diseased fruits, so as to reduce the chance of bacteria invading through the wound. Remove residual petals and stigmas in time to prevent bacteria from harming plant leaves or fruits through residual petals or stigmas.

(2) reduce the dosage and concentration of hormone during flowering. Improper use of hormones will cause petals not to take off, even if the air outside is relatively dry, but the humidity of the dry petals between sepals and fruits is still very high, Botrytis cinerea is easy to invade and harm.

(3) low temperature and high humidity is the primary condition for the outbreak of Botrytis cinerea. In the process of cultivation and management, attention should be paid to keeping roots and leaves, keeping fruits reasonably, cultivating strong plants and enhancing stress resistance, and always pay attention to adjusting the temperature and humidity in the shed. Laying rice husk, straw or straw for moisture absorption.

IV. Chemical control

The main control agents: pyrimidine, permethrin, ethamyl, isocarbamide, thiram, sclerotiorum, pyrazolyl ester, pyrimidinamide, fluazolamide. Reference for prevention and control period:

(1) the end of florescence: to control the infection of early pathogens in grape clusters.

(2) bunching period: to reduce the number of pathogens infected by stems and pedicels.

(3) the initial stage of fruit ripening: prevent grape berries from sagging.

(4) three weeks before harvest: prevent the re-expansion of initial infection bacteria.

(5) before harvest: mainly to prevent the occurrence of Botrytis cinerea in the process of transportation.