The PGRO is examining ways to cut herbicide costs by reducing doses of Basagran (benzatone) by mixing it with some adjuvant oils.

Jim Scrimshaw, PGRO senior technical officer, said the cost of some bentazone formulations at around £60/ha for a full-rate application to spring beans remained an uneconomic option for growers.

However, initial trials in spring beans have suggested that adding oils, like Actipron, Headland Fortune, Toil and Kantor to Basagran allows costs to be reduced without necessarily losing significant product efficacy or increasing crop damage.

“We want to see if Basagran can be more flexible and not as prohibitively expensive for growers to use without compromising weed control,” said Mr Scrimshaw.

Dose response data was being recorded for the first time this year. In the future it is hoped that “a rate” to control “a particular weed” will be better understood, but there are several variables to consider and it will take several years before any reliable results are available, he added.

There are currently no recommendations from agrochemical companies for adding adjuvants to Basagran when used in spring beans.

Mr Scrimshaw also mentioned that, under the current European pesticide review, the key herbicide pendimethalin could potentially still be lost in 2013. This would be a huge blow to growers, who were already reeling from the loss of other herbicides.

But he added: “Makhteshim and BASF have recently brought out alternative pendimethalin products with new formulations – Cinder and Stomp Aqua.

“They must be confident of keeping pendemethalin. You don’t invest that kind of money developing and launching a new product for it then to disappear in 2013.”