Gray mould is the most common disease of grape, and it also has serious impact on the growth of grape which can cause a large amount of grape production and do harms to the fruit and plants, so we must pay attention to it.The incidence of grape gray mould is closely related to humidity and light, and the incidence is very high in continuous rainy weather conditions.Seeing form the whole growth period of the grapes.If grapes are infected with gray mould,it is easy to cause rot in buds, flowers, fruit, branch.

1.Symptoms of grape gray mould

If the grapes are infected with gray mould at the stages of inflorescence and young fruits,there will have light brown spots on the peduncles and stems and then change to brown and begin to rot. when the air is wet, there will have gray mould layer and when the air is dry, the infected inflorescence and young fruit gradually lose water, wither, dry, fall off.

2.Incidence Characteristics

The bacteria of the disease are oospore overwintered in residues of diseased plants and the soil.In the spring of the next year, new roe deer can be produced, through the airflow to the inflorescence of the flower, young fruit, and then through the fruit wound, natural stomata, and young tissue invasion, resulting in the disease.The temperature 21℃ and humidity 95% is the most suitable for the development of the bacteria.

3. Drug prevention and control

The commonly used fungicides and their prevention and control characteristics are mainly as follows:

(1)Iprodione

Prevention is the main, treatment is the supplement.It is characterized by wide applicability, good safety, but has no internal absorption.At the same time, the effective period is long.

(2)Pyrimethanil

It is based on the principle of mainly treatment,supplemented by protection.It is characterized by a good internal absorption and conductivity.But it can not be used at the high temperature above 30 degrees.More ventilation should be needed after applying.It is recommended to spray 40% pyrimethanil 1000-1500 times liquid at the onset of gray mould.

(3)Cyprodinil

It is based on the principle of mainly protection,supplemented by protection.It is characterized by a good internal absorption.But it has antagonism to pyrimethanil.It is recommended to spray 50% cyprodinil 800times liquid before the occurrence of the disease.

(4)Fludioxonil

It is based on the principle of mainly protection,supplemented by protection.It is characterized by strong protection function, long efficacy period, but not internal absorption.It is recommended to spray 50% fludioxonil 3500 times liquid before the occurrence of grape gray mold.

(5)Boscalid

It is both protective and therapeutic effect.It is characterized by good control effect on fungal diseases, long validity period, good temperature adaptability.However, it is not suitable for grape growing areas with long-term use of pyrimethanil.It is recommended to spray 50% Boscalid 1500-2000 times liquid to prevent and control the disease.

Zhengzhou Delong Chemical CO., Ltd. is the production base of plant growth regulators in China, which established in 2009, specializing in offering plant protection products. If you have any question, contact us any time.