Post-emergence options for blackgrass control have been boosted for this autumn after the approval of a new grassweed herbicide.

GF-2070 from Dow AgroSciences could offer an alternative to Atlantis (iodosulfuron + mesosulfuron) for post-emergence blackgrass control.

It is a co-formulation of pyroxsulam, the main active ingredient found in Dow’s other grassweed killer, Broadway Sunrise, and flupyrsulfuron-methyl, sold by Dupont as Lexus SX.

“GF-2070 is a competitor to Atlantis in the post-emergence blackgrass market,” confirmed Stuart Jackson, Dow’s agronomy leader. “In terms of blackgrass control, trials show it is every bit as good as Atlantis and there are additional benefits, too.”

Compared with existing post-emergence blackgrass products, it has a better grassweed and broad-leaved weed spectrum, including cranesbill, groundsel, volunteer beans and pansies, he said.

“It also has good following crop flexibility as there is no need for growers to do any cultivations prior to sowing oilseed rape.”

GF-2070 is being promoted for blackgrass control as part of a programme to be used with products with other modes of action. Autumn is the main focus of timing, however, like Atlantis it can be used in the spring.

“Typically, GF-2070 can be used following a pre-emergence programme with Crystal (flufenacet + pendimethalin) or Liberator (flufenacet + diflufenican),” said Mr Jackson.

“It offers greater adjuvant flexibility and it can also be tank-mixed with a range of residual herbicides, such as Stomp Aqua (pendimethalin) or Defy (prosulfocarb).”

However, growers who use Lexus at the pre-emergence stage will not then be permitted to apply GF-2070 post-emergence, nor will growers be able to use Atlantis in the same crop.

Although GF-2070 comes from a different class of chemicals to Atlantis, its mode of action is the same, so it offers no advantages in terms of management of resistant blackgrass, said Mr Jackson.

“If you have got ALS inhibitor resistance on your farm it will perform in exactly the same way.”

GF-2070 will be priced similarly to Atlantis, said Mr Jackson. However, it will not be given a brand name until next autumn, although Dow aims to make available as much product as possible this autumn.