Check the products for compatibility in each case.
Grape: Presto Plus 72 WP is most effective when applied prophylactically prior to infecting or after a maximum of 1-2 days after infecting. The use of the product for the first treatments is especially effective. Under normal weather conditions, it is recommended to apply Presto 50 WP with an interval of 10-12 days. In rainy conditions, especially in the period of intensive growth, when the risk of infecting is particularlyhigh, the interval between treatments is recommended to be reduced to 7-8 days. The dose rates of the working solution and hectare dose depend on the phase of development of a crop and the degree of development of the disease. Minimum doses are used at low infectious background, and at the beginning of the vegetation period, the maximum – with the full development of the leaf surface or a highly infectious background. Treatments are most effective in the early vegetation period as well as the first signs of the disease.
Potato: Treatments against late blight should be not for curing, but for prevention of a disease. When 1% of the leaf surface is affected, the treatment becomes ineffective, when 10% – it is impossible to stop the progression of the disease. The first treatment is usually carried out before the first signs of late blight, in the phase of end of budding – the beginning of flowering. It is necessary for the plants to be under the action of fungicide during the whole period of vegetation, until harvesting or pre-harvest top-killing, as an affection of tubers by a late blight can be strong even at a weak affection of the foliar parts of the plants. Spraying against Alternaria, compared to late blight, can be carried out after detection of symptoms of a disease, in case the affection of the foliage part of the plant does not exceed 1%.