The main target weeds were those which predominately germinate during the winter period when field travel can be difficult, namely field pansy, wireweed and mallow etc.

Between 2011 and 2013, no experimental herbicides evaluated provided additional control of these weeds while being safe towards Red Beet. The safest treatments towards red beet included the currently used products Betanal® Forte, Nortron®, Goltix® among others (and their active ingredient counterparts) when used at appropriate rates and combinations for plant size. However, as weeds escaped the low rate repeat applications commonly used, it is obvious that other products are required.

In 2013, autumn applied diflufenican (DFF, applied as Quantum®) was too tough on red beet, while it was identified that winter/spring application was not as detrimental towards crop growth and provided good control of field pansy, when field pansy was small. Early growing season control using other products was still required.

Therefore, in 2014 a trial was set up to compare DFF application, either alone or in combination with other commonly used products, for effects on seed yield and subsequent seed germination. Seed yields are presented as kg/ha and adjusted to include the male row area.

Harvest was undertaken by direct cutting using a small plot combine with side knives cutting across the female rows following desiccation using diquat. Following harvest, two subsamples from each plot were cleaned by hand sieving to remove stem residue and small seed. Seed germination testing was undertaken twelve months following harvest. Seed was stored in paper bags in a ‘cool room’ to represent worst-case storage to separate treatment effects.

Results

Seed yield and germination were not affected by any of the herbicide treatments applied, however additional weed control did not improve seed yield.

FAR recommends that growers should always consult their agronomists before implementing decisions concerning herbicide use.

NB. Use of product in these trials does not constitute a recommendation.