What pesticide works well for yellowing grape leaves?

Grape is one of the oldest fruit tree species in the world and is cultivated all over the world. So, during cultivation, what pesticide should be sprayed for yellowing grape leaves?

1. What pesticide should be sprayed for yellowing grape leaves?

1. Caused by lack of nutrients: spray foliar fertilizer regularly and apply compound fertilizer as a top dressing;

2. Caused by disease: a special-effect fungicide can be sprayed, which can kill fungal and bacterial diseases and other problems, and can promote the rapid recovery of yellowing grape leaves;

3. Caused by pesticide damage or fertilizer damage: spray clean water on the leaves and irrigate the roots to dilute the fertilizer solution on the grape leaves and reduce the damage.

2. Causes of yellowing grape leaves

1. Leaf yellowing caused by nutrient deficiency in grapevines

Grapevines absorb different amounts of various elements at different growth stages, and when a certain element is lacking, corresponding symptoms appear on the leaves. Extensive field observations show that yellowing caused by nutrient deficiency in grapes is mostly related to the lack of iron, potassium, magnesium, boron and other elements.

(1) Iron deficiency: mainly shown on young shoot leaves, while old leaves are basically normal. In iron-deficient leaves, the veins remain green and the areas between the veins turn yellow.

(2) Magnesium deficiency: yellowing is mainly shown on old leaves, commonly occurring on middle and lower leaves, with chlorotic yellow spots appearing along the leaf margins and between the veins.

(3) Potassium deficiency: yellowing and death generally begin at the leaf margins, and the leaves curl upward or downward, with the leaf surface appearing twisted or uneven.

(4) Boron deficiency: it generally appears on leaves as water-soaked pale yellow spots on young leaves, gradually followed by loss of green along the leaf margins and between the veins, shrinking and deformation of new leaves, and later the leaf margins turn yellowish white and may even become scorched and withered.

2. Yellowing caused by pesticide damage: spraying may be affected by weather conditions, application methods and pesticide quality and other issues, resulting in pesticide damage. After pesticide damage occurs in grapes, yellowing often appears on the leaves, generally showing about 4 days after application.

3. Yellowing caused by fertilizer damage: fertilizer damage can damage the grape root system and cause leaf yellowing.

4. Yellowing caused by disease: many infectious diseases of grapes can cause leaf yellowing, and compared with physiological yellowing, it is relatively easier to identify.

There are many causes of yellowing grape leaves, so the cause needs to be identified first, and then corresponding treatment measures should be taken.