Grenade new weapon in weed control

GROWERS in WA's eastern Wheatbelt and lower-rainfall zones have an opportunity to boost weed control during the cereal phase of their cropping programs after the release of new double-gene Clearfield Plus Australian Premium White (APW) wheat variety, Grenade CL Plus.

Bred by Australian Grain Technologies (AGT), Grenade CL Plus shares a similar maturity to the State's most widely grown wheat variety, Mace.

AGT marketing manager Nick Joyce said growers in medium to low-rainfall environments now had a better adapted wheat variety for their farms than the only other two-gene Clearfield wheat available, the later-maturing Justica CL Plus.

Registered for use with the imidazolinone herbicide Intervix at a maximum rate of 750ml/ha, Grenade CL Plus provides an early spraying opportunity from the three-leaf crop growth stage for the control of problem weeds such as brome and barley grass, along with many others that fall under the "imi" chemistry group.

"Grenade CL Plus, with its shorter maturity, improved hectolitre weight and CCN resistance, provides a more widely adapted Clearfield herbicide option over sister line Justica CL Plus for lower rainfall and shorter growing season environments," Nick said.

"It has a sound rust resistance package but is rated susceptible to yellow spot, which means a fungicide may be warranted in season."

Meckering farmers Ray and Ty Fulwood grew the first and only production paddock of Grenade CL Plus in WA last year.

"We sowed Grenade CL Plus at 42kg/ha on June 11 into a 60ha paddock that had canola stubble from the previous year and averaged 3.3t/ha," Ray said.

"Yellow spot was infecting the lower leaves in early September and we made a decision to spray tebuconazole, which was a good move considering we had 100mm of rainfall in early spring. At harvest the grain quality was excellent."

Recognising the strong performance of Grenade CL Plus in South Australia in 2012, north-east Dalwallinu farmer Keith Carter, through his local reseller, "jumped the queue" early and ordered 1 tonne via an AGT affiliate.

"We were looking for another cereal to pair with Scope CL barley, with brome grass being the major weed on our red loams," Keith said.

"Also, barley prices are not always comparable to wheat so we have two Clearfield varieties to spread the price risk.

"Grenade CL Plus is better adapted to our environment with its shorter maturity and it will effectively replace Justica CL Plus. Unfortunately, Justica CL Plus was the only double-gene Clearfield wheat option until now and was not the best fit with its longer maturity. It also recorded lower hectolitre weights in comparison to Grenade CL Plus.

"We sowed 25ha to Grenade CL Plus last season and it yielded between 1.6 to 1.8t/ha.

"This year we plan to dry-sow 210ha to Grenade CL Plus, along with Scope CL. Dry sowing and using Intervix for weed control once we have received rain has become a very profitable crop system for us."

A small quantity of Grenade CL Plus seed is available through AGT Affiliates for the 2014 season. Larger commercial volumes will be bulked up this year.