BASF launches acaricide Nealta in the UK

BY JOHN SWIRE

- The active cyflumetofen is from a unique class of chemistry, Group 25
- Kills all stages of mites – eggs, immature stages and adults
- Compatible with beneficial predatory mites and other insects
- Ideal as a rotation option in an ICM programme

BASF launches a new acaricide, Nealta. It is based on the new active ingredient cyflumetofen, which is from a unique group of insecticides, Group 25. It will also kill all stages of the mites’ life cycle – eggs, immature stages and adults- whilst being compatible with beneficial mites and other insects such as bees.

Nealta is currently recommended on apples, ornamentals in plant production and protected strawberries. Formulated as a suspension concentrate, it is applied at a dose rate of just 1 l/hectare. One of its key benefits to growers is that it has a unique mode of action, not found in other acaricides, making it an excellent resistance management tool against mites on some horticultural crops. Applied as the first application in the mite control programme, Nealta gives strong knockdown and residual effects on mites, whilst unaffecting predatory mites released in the season, other insects and bees. Controlling mites requires protecting natural enemies as much as possible by using products like Nealta that are the least harmful to beneficials. Only one application is allowed per crop and Nealta has a Harvest Interval of 1 day for protected strawberries and ornamentals and 14 days for apples.

Rob Storer for BASF says controlling mites is a difficult process as there is widespread resistance to the many groups of chemistry available. Most crops that suffer from mites require season-long protection, with multiple sprays. Nealta brings a new insecticide group with a new mode of action which has the ability to be safe for beneficials including bees and predatory mites such as Phytoseilius and other insects. “It brings all the attributes growers are after, including helping to protect other chemistries from resistance build up.”

Red spider mites are tiny oval shaped microscopic pests with eight legs, 0.5 mm in size, and a red to brown colour. The adults produce silky threads hence the name red spider mites. They are generally found on the undersides of the leaves and they suck out the contents of plant cells. Although very small individually, they have a great reproductive capacity, which is dependent on temperature and Relative Humidity, and large numbers of mites can adversely affect yield and quality of the fruits.

An infestation in strawberries tends to reduce the number of fruits, not the size of them. In ornamental production it is the stippling or bronzing of the leaf; in other words the visual appearance of the plants which is the problem. In soft fruit, mites are generally red spider mites and tarsonemid mites. In apples, red spider mites overwinter as eggs on bark, close to fruiting spurs with eggs hatching late April to May, at blossom time. The immature stages which look like the adults but smaller invade leaves and trusses and their feeding causes leaf bronzing, fruit russetting and in severe infestation leaf drop. Certain varieties such as Discovery, Gala and Worcester Permain are susceptible.

“With Nealta the risk of resistance is lessened and both conventional and biological approaches can be integrated into a flexible control programme. We will be looking to add to the recommended crops in the future,” says Mr Storer.