Powdery mildew is often seen in the summer. In contrast to other fungi, powdery mildew also likes warmth and drought. Their spores can also germinate at low relative humidity because they already contain a lot of water. In many other fungi this is often not the case. Powdery mildew thrives best at temperatures between 16-27 °C. In the greenhouse this often leads to a huge increase in powdery mildew, precisely because during this period the greenhouse is aired more and the spores are easily spread throughout the greenhouse.
From April through September, Solvit can be used, for instance in cut roses. In 2015 and 2016 good results were achieved, and this season growers have again successfully used Solvit. Wesley Akkermans of Syngenta Crop Protection: "In particular, curative action is highly appreciated. Solvit is used both spot-wise and in the entire field to rapidly stop the increasing mildew pressure. The duration effect is also clearly apparent and growers can extend the intervals between the mildew sprayings by days. In addition, the importance of changing the used fungicides in time to prevent resistance is well known. Solvit is a welcome alternator within the current package of mildew products and can be safely used in roses until the end of September."
Over 2 years ago, Solvit was allowed to fight powdery mildew in the cultivation of roses and gerberas. Between April 1 and September 30, Solvit can be used in roses in 2 blocks of 3 applications each.
How does Solvit work?
Solvit's strength lies in the combination of 2 active substances with a different action mechanism. This causes the mildew to be attacked on two fronts, and results are soon visible. There is contact action on the leaf surface immediately after application and local systemic operation by intake in the leaf. The mildew spots become gray and dry up. Eventually only dark-purple spots on the leaf remain of the earlier mildew attack.
Wesley Akkermans: "Several tests have repeatedly shown that Solvit has a very good curative effect, but also the long-term effect is excellent. Up to 3 weeks after the last application, a controlling effect is perceived."
A concentration of 75 ml of Solvit per 100 liters of water is recommended at a water volume of 1,500 liters of water per hectare. At higher water volumes, Solvit concentration should be reduced proportionately, in such a way that 1,125 liters of Solvit is applied per hectare. The use of higher dosages increases the risk of crop damage. Drip from the crop must be prevented to avert insufficient effectiveness. Therefore, it is recommended to use no more than 3,000 liters of water per hectare for the mildew control.
Solvit should be applied in block applications of up to 3 sprayings with 7-day intervals. Because of the build-up of the active substance in the crop with repeat applications, mildew is optimally controlled.
Solvit must not be applied during very severe weather and the crop should be kept wet for at least 1 hour.
If no experience has yet been gained with a product or combination in a specific crop, a test spraying should always be conducted on a small scale to determine whether the crop tolerates the product or combination.
For more information, please contact:Syngenta Crop Protection
Wesley Akkermans, Crop Advisor
T: +31(0)6-12 66 02 33