UK growers will be the first in Europe to have access to two new potato products based on novel chemistry, says Bayer CropScience.

The first, Infinito, is a protectant blight fungicide based on the new active ingredient fluopicolide, combined with propamocarb.

“Fluopicolide has a unique, multi-site mode of action that causes disruption of the [blight] cell membrane and destroys the disease before it’s had time to multiply,” says Bayer’s roots product manager, Andy Albert.

Its combination with propamocarb offers anti-sporulant, translaminar, systemic and protective activity against foliar blight, and it is particularly suited to the middle to later stages of crop growth, he says.

“We see it fitting from full haulm growth through to senescence.”

While there is no minimum application interval on the label, under low-moderate disease pressure, he suggests it should be used at 1.2 litres/ha at seven-day intervals, or 1.6 litres/ha at 10-day intervals.

In higher disease pressure situations, the full recommended dose of 1.6 litres/ha should be used at seven-day intervals, he says.

“A key strength of the material is its environmental profile – there is no LERAP, so fields near waterways don’t require buffer zones,” he notes.

“Providing it has had time to dry on the leaf surface, it should also be rainfast in one hour.”

Infinito compares well to standard Curzate-based programmes (cymoxanil + mancozeb) for controlling tuber blight, adds development manager, Eileen Bardsley.

In 2004 SAC trials, a combination of 3x Curzate, 3x Infinito (1.2 litres/ha) and 3x Electis (mancozeb + zoxamide) reduced the incidence of tuber blight from about 13% in the untreated control to about 9%, she says.

Using a similar programme with the 1.6 litres/ha rate of Infinito reduced incidence to 6%, compared to about 8% infection after a 6x Curzate and 3x Electis programme.

Bayer’s second new product is a foliar insecticide based on thiacloprid, using a novel oil-based formulation technique which Bayer claims increases the efficacy of systemic crop protection agents.

suspension

“Thiacloprid is from the chloronicotinyl (CNI) class of insecticides and it controls all important aphids, including those that are MACE resistant,” says the firm’s Bill Lankford.

The new “O-TEQ” formulation uses a sunflower oil-based suspension, combined with crystals to provide a gradual release of the compound, he says.

“We are aiming to match the level of conventional EC products, while avoiding the use of solvents.”

The formulation improves spread on the leaf surface, speeds up penetration and improves rainfastness, he says.

“We have found nearly 50% penetration within two hours, followed by more gradual penetration over time.

The oil is retained after water evaporates, which binds the active ingredient to the leaf.

This can be a big advantage where the weather is catchy.”

In Bayer trials last year, Biscaya provided just over 80% aphid control three days after application, which was similar to Aphox (pirimicarb), but about 30% better than Plenum (pymetrozine), which is slower to get going, he says.

By 21 days after treatment, Biscaya and Plenum gave about 75% control, while Aphox showed shorter persistence with about 45% control, he notes.

Like Infinito, the product has no LERAP restrictions and it also has low impact on beneficial insects such as lacewing, ladybird, hoverfly and honeybee, Dr Lankford says.

“This means it can be fully compatible with an IPM programme.”

While the product is only approved for use in potatoes and oilseed rape, Bayer is hoping to extend it to other brassica crops next year.

“Any systemic crop protection product – particularly EC products using solvents – could benefit from this O-TEQ formulation technology,” he concludes.

Biscaya and Infinito are already on Tesco’s Nature’s Choice 2006 Plant Protection Product List (PPPL) and Bayer is in talks with other retailers and their suppliers.

Prices are likely to be announced at the beginning of April, and it is expected that Biscaya will be at a premium to existing products.

paul.spackman@rbi.co.uk