14 November 1997

Bulb fly killer stays on guard for months

A NEW wheat bulb fly killer has received full approval for use in winter and spring varieties of wheat, barley and oats.

Growers sowing late wheat after roots this autumn will be able to use Evict to protect crops for several months after drilling, says Peter Froggatt of maker Zeneca Crop Protection.

Active ingredient tefluthrin, a soil-acting pyrethroid insecticide, is contained in micro-capsules which progressively release the product independently of soil moisture.

ADAS forecasts show the risk of extensive damage from wheat bulb fly is likely after last years high levels. John Young of ADAS Boxworth reckons 25% of all fields in wheat bulb fly affected areas like the eastern counties and Yorks and Humberside contain more than the 2.5m eggs a hectare threshold, putting them at high risk. Last year 31% were in that category.

Evict is applied at 2 litres/t of seed, equivalent to 40g/ha at a seed rate of 200kg/ha, less than a fifth of the rate of fonofos, which tefluthrin will replace, Mr Froggatt notes.

Average yield rises of 1.8t/ha (0.72t/acre) have been achieved in trials during the past eight years using Evict. Results are usually ahead of and never below fonofos, he adds.

Cost is £74/ha, slightly more than fonofos. &#42