New herbicide option for outdoor sunflowers

The herbicide active substance ‘aclonifen’ is now authorised as ‘Emerger’ for use in outdoor sunflowers.

The authorisation was secured by the AHDB crop protection team, which specialises in Extensions of Authorisations for Minor Use (EAMUs) in horticultural crops.

Aclonifen provides growers of outdoor sunflowers with a valuable pre-emergence broad-leaved weed control option, this spring.

Vivian Powell, who led the application at AHDB, said: “Broad-leaved weed control in outdoor sunflowers relies largely on pre-emergence products that contain the active ingredient pendimethalin.

“This chemistry has struggled to get on top of some weeds, such as cleavers, redshank and black-bindweed, offering little or no pre-emergence control. As post-emergence sprays can be highly damaging to sunflowers, the authorisation of aclonifen will significantly improve the spectrum of weeds that can be controlled in this crop.”

The EAMU (1615/2019) relates to the use of ‘Emerger’ (M19056) as a pre-emergence herbicide for the control of mayweed, fat hen, cleavers, shepherd’s-purse, chickweed, nettle, speedwell, knot-grass, black-bindweed, redshank, oilseed rape, crane’s-bill and sow-thistle in outdoor sunflowers.

The active substance aclonifen is authorised for use on a range of crops, including sunflowers, in the rest of Europe. This EAMU is based on Mutual Recognition of an authorisation in Lithuania.

Growers interested in the product should refer to the advisory information on the notice of authorisation published on the CRD website.

Extensions of Authorisation for Minor Use

Under Article 51 of Regulation (EC) 1107/2009, both authorisation holders and growers or grower organisations can apply for an extension of use. This is defined as an extension of authorisation for minor uses of existing authorised products. The extension can be given where the use is minor in nature, is in the public interest and all safety aspects of the risk assessment can be satisfied. When an extension of use is given, it can appear on the product label in a separate section titled 'Extension of Use' and, in this case, with the following text:

"This extension of the authorised use provides for the use of the Emerger in respect of crops and situations, other than those included on the product label. No efficacy or phytotoxicity data have been assessed and, as such, the 'extension of use' is, at all times, done at the user's choosing, and the commercial risk is entirely theirs."

The product authorisation holder can decline to put the extension of use on the product label, but it is available as an Extension of Use Notice on the CRD website.

AHDB and the EAMU Programme

With the continuing loss of crop protection products, AHDB Horticulture has run an EAMU programme for many years. An in-house team of crop protection specialists work with industry to manage and make applications. If you have identified an area in which you think the EAMU programme could help, visit the AHDB Horticulture EAMU page.