The blight fungicide Electis, which contains zoxamide® and mancozeb, has one of the highest ratings for the control of Alternaria or early blight in potatoes as well as one of the best ratings for protectant activity against late blight and a very acceptable rating for tuber blight.
In support of this claim, John Edmonds, European Technical Manager for Gowan Comércio, reports that in the Euroblight ratings Electis has a two and half star efficacy rating for Alternaria solani and Alternaria alternata (in a three star rating system). "This rating, which is assessed by a panel of independent experts, puts Electis above all other mancozeb-containing products on the market, including straight mancozeb itself. Electis also has a two and half star rating in the listing issued by the Dutch Crop Protection organisation (PPO), making it the best mainstream product for Alternaria. Infinito, Ranman and Revus have no activity according to this table. "
"This technical data is backed up by excellent practical results with Electis in Germany, The Netherlands and Northern France in the field and in particular in six trials in Spain which resulted in over 70% control of Alternaria. Of all the products registered for the control of potato late blight, Electis shows the best efficacy against potato early blight."
"There has been a lot more concern about the increased threat of Alternaria, or early blight, in potatoes in the UK in the last two years, and this new disease has already been found in the popular varieties such as Markies, Saturna or Estima. Alternaria appears to have become more significant because of the weather conditions and also the changing fungicide usage, with lower mancozeb usage overall," he says.
"But it rarely appears in isolation and as late blight continues to be as the primary disease by which fungicide programmes should be driven, it must be tackled with a fungicide that offers proven activity on both diseases, early and late blight. As many growers in Europe will testify, Electis has been used successfully against both blights for a number of years," explains John Edmonds.
John explains that although Electis doesn’t have label approval for Alternaria in the UK as yet, it does have full label approval in some European countries including France and the Netherlands, where this disease has been a significant problem for many years.
"The continental climate favours Alternaria over Phytophthora (or late blight) and, if our temperatures continue to rise, as they are expected to do, we are likely to see more Alternaria in our crops. Realistically applying a fungicide solely for the control of Alternaria is just not practical or indeed cost-effective in the UK, however. You need a fungicide that has excellent and reliable activity against both late and early blight plus proven activity against foliar and tuber blight - Electis is the only product that delivers all this," says Mr. Edmonds.
®Electis contains 8.3% w/w zoxium (zoxamide) and 66.7% w/w mancozeb, formulated as a WDG. It is recommended on all varieties of potatoes at spray intervals of 7 to 14 days. It has a dose rate of 1.8 kg/ha in 200-600 litres of water per hectare. It has a maximum number of treatments of 10 per crop and a harvest interval of 7 days. It is packed in a 3-ha pack (5.4 kg).
