Hello! From the pictures and information given, the grapevine seems to be attacked by the woolly vine scale, Pulvinaria vitis (The woolly vine scale (Pulvinaria vitis) - pest management). On the foliage are the sweet “honeydew” droppings left by the pests, on which the Capnodium species of fungus grows, and the vine leaves are covered with a black film called sooty mould. In this case, it is recommended to treat after harvesting the grapes, with insecticides such as , in a dose of 7.5 ml/10 L water or , in a dose of 3 g/10 L water. Two treatments can be carried out at 7-day intervals. Specifically, if you carry out the first treatment with , you can carry out the second treatment with , 7 days after the first. To increase the effectiveness of the insecticides, it is recommended to add an adjuvant such as , to the solution at a dose of 2 ml/10 L. Spray the mixture as finely as possible so that it is distributed evenly on the plant.
This autumn it is recommended to start treatments (winter treatments with copper-based oils and products) during dormancy (after leaf fall) with copper fungicides such as (50 g/ 10l water) or (dose of 20g/ 10l water), and with a horticultural oil such as , , – these treatments are used to control some pests that may be in hibernation.
Before carrying out the treatments, it is recommended to carry out a clean-up (pruning, removal of old branches, gathering of plant debris, etc.).
Also during this period, a fertilizer with a high potassium content can be applied, ideal for autumn fertilization , which increases the resistance to frost (the recommended dose is 30-50g/sqm).
More information and care tips can be found in our article: Vineyard - Fertilization and Irrigation.