The aphicide Biscaya (thiacloprid) has been granted Specific Off Label Approval for controlling aphids in a range of brassica crops (e.g. broccoli, Brussels sprout, cabbage, calabrese and cauliflower), it has been announced.

The decision gives growers an effective alternative to triazamate, which is being withdrawn* under Europe’s ongoing review of approved pesticide products (EEC 91/414), says the Horticulture Development Council’s Vivian Powell, who applied for the SOLA.

“The withdrawal of triazamate has left growers without an effective means of controlling mealy cabbage aphids.

“At the same time, we felt that being able to use Biscaya on brassica crops would help growers to develop a more robust resistance strategy – an important factor in the urgent case that was submitted to PSD [Pesticides Safety Directorate].”

Biscaya is thought to be particularly useful in cooler, windier weather against mealy cabbage aphids and peach potato aphids, although growers are advised to adhere to a single application at the recommended 0.4 litres/ha rate.

*The decision to withdraw triazamate was announced in September 2005, to take effect from January 2006. But growers were given 12 months to use up remaining stocks, noted Ms Powell.