Professional potato growers know all about the need to grow blight–free potatoes and will plan and implement a robust, no-nonsense blight prevention programme, with tight spray intervals, from the rosette stage right through to harvest. But if they want that added extra security from their blight fungicides, new evidence has shown that the addition of the specialist adjuvant Banka will pay dividends, according to Alan East, Technical Manager for Interagro Ltd.
"Potato planting this year was late and crops went into cold soils, leading to slow emergence. Now that crops have emerged, the weather has turned warmer and wetter, ideal for blight to sporulate and spread. With most crops being irrigated, blight control programmes will have started at emergence and will need to continue right up to harvest, in order to produce the quality potatoes that supermarkets and processors have come to expect," says Alan.
He states that recently blight control has become more challenging with the more aggressive A2 blight strain dominating UK populations. "This strain thrives at lower temperatures, causes larger lesions and has a shorter latent period. There is also the additional threat of late blight, Alternaria. It’s not easy, but independent trials have shown that Banka, a patented adjuvant for potatoes, can help ensure top performance of contact, translaminar and systemic blight fungicides, traditional as well as the many new ones."
"In independent trials, the addition of Banka to Ranman (cyazofamid) in a blight programme increased marketable yields by 0.9 t/ha. When added to Revus (mandipropamid), it resulted in extra marketable yield of 1.8 t/ha. With Roxam/Electis (zoxium and mancozeb) it gave an extra 2.4 t/ha and with Valbon (benthiavalicarb-isopropyl and mancozeb) an extra 6.1 t/ha over the untreated. The more traditional blight fungicides, such as fluazinam (Shirlan) and mancozeb (Dithane) also benefit," says Alan East.
He explains that Banka enhances the coverage and performance of all major blight fungicides with each of its component adding to the equation. "Initially the alkyl pyrrolidones in Banka help to disperse the fungicide in the spray tank, making the overall spray operation easier. Then its sulfonated surfactants ensure more even deposition and spread of the fungicides across the leaf surface, resulting in better disease control. Its alkyl pyrrolidones also aid penetration into the plant, making the fungicides more effective. Then its polymers act as stickers, aiding retention and providing better rainfastness and weathering, vital in irrigated crops and catchy weather. Banka’s micro-emulsion formulation ensures that there are no blocked nozzles or pumps."
Banka is recommended at 0.075% to 0.15% of the total spray volume e.g. 75-150 ml in 100 litres of water per hectare or 150-300 ml in 200 litres of water per hectare. Higher rates are used if there is high blight pressure, in wet weather or in irrigated crops.
