Blackcurrants: Screening herbicides for safe use in recently planted cuttings

The Problem:

Blackcurrant cuttings present a particular challenge with respect to weed control. In their first couple of years, the cuttings themselves are not very competitive and provide little shading, meaning that growers must pay particular attention to weed control so that establishment is not compromised.

Ronstar has been widely and successfully used for many years, but successor materials are required now that Ronstar is no longer available.

The approach proposed is to plant a trial area and, immediately after planting, to treat individual test plots with all of the currently approved blackcurrant herbicides, and in addition, a small number of materials whose registration on currants is either underway or thought to be possible.

Benefits to industry

If successful, the project would deliver information to growers about the effect of herbicides on cuttings in order to facilitate product selection to reduce weed competition without reducing rooting, shoot growth or vigour in newly planted blackcurrant.

Dissemination of the results will be through an HDC News article and if appropriate, presentation at an industry event.

Aims and objectives:

• To enable growers to select herbicides that are not damaging to newly planted blackcurrants.

• To investigate the phytotoxicity of 9 herbicides, applied to cuttings within 48 hours of planting.
• To investigate the ‘safety margin’ and risk associated with each herbicide.
• To investigate the ‘sub lethal; effects – i.e. growth suppression