National Working Party on Grain Protection (NWPGP) chair Gerard McMullen is urging canola growers to adhere to label application directions on herbicides containing haloxyfop as part of an industry-wide effort to avoid unacceptable chemical residues.
For herbicides containing haloxyfop as the active ingredient, label directions stipulate they must not be applied to canola and other specified oilseed crops:
- After the eight-leaf growth stage
- After the stem elongation growth stage has commenced (this may occur before the eight-leaf growth stage, so determine the crop growth stage before application)
- Under or between windrows (this is not a registered label use and could result in chemical residues) .
Of the haloxyfop herbicide products available in Australia, Verdict™ 520, Asset™ and Inquest® herbicides are examples of those commonly used by canola growers.
Highlighting the importance of complying with label directions, Mr McMullen says residue testing by the National Residue Survey has detected haloxyfop residues above the Australian maximum residue limit (MRL) in canola traded domestically, which is of concern.
Also, the European Union (EU) Australias main canola export market is implementing new, tighter import controls.
Mr McMullen says the EU has indicated it plans to lower its current haloxyfop MRL for canola to 0.05 milligrams per kilogram.
Although still to be finalised, this revision reducing the haloxyfop MRL for canola sold into EU markets is expected to occur in the first half of 2019. The haloxyfop MRL for Australian canola exports to Japan, another major market, remains at 0.1mg/kg.
Australian grain growers have a very good history of compliance with product label directions and, as an industry, we need to ensure that haloxyfop continues to be used in accordance with label directions, Mr McMullen says.
Growers are also encouraged to consider other herbicides containing products with different active ingredients for in-crop control of grass weeds in canola.
New working group
Tackling the trade risks that haloxyfop residues pose to domestic and export canola markets, the Australian grains industry has established a Haloxyfop Working Group, the need for which was flagged at the annual NWPGP Conference in Melbourne in June 2018.
Also chair of the Haloxyfop Working Group, Mr McMullen says the new groups first meeting in December 2018 short-listed a series of steps, supporting previous industry measures, with the aim of further reducing haloxyfop residues in canola.
An industry advice notice was issued to the post-farmgate sector, including grain-storage providers, marketers and traders, emphasising the importance of managing the haloxyfop risk when supplying canola to important markets, such as the EU, Mr McMullen says.
Australian grain growers have a very good history of compliance with product label directions and, as an industry, we need to ensure that haloxyfop continues to be used in accordance with label directions
The strategy outlined in that notice included rigorous sampling and testing of canola grain for haloxyfop residue as part of standard post-farmgate practice, which will allow grain to be selected for different markets based on its residue status.
Residue testing methods for haloxyfop have also been reviewed to ensure they are consistent with those used in export markets.
Another development is that the Haloxyfop Working Group has initiated research to determine the main cause of haloxyfop residue in canola grain and oil.
This research aims to examine canola at all stages of the supply chain, from on-farm application practices to grain harvested and commingled in storage.
Research tracing haloxyfop all the way through the canola supply chain would help provide a better picture of where residues might be arising in marketed grain, Mr McMullen says.
GRDC crop protection officer west, Georgia Megirian, reiterated the importance of adhering to label directions when applying herbicides containing haloxyfop.
Applying haloxyfop to canola after stem elongation will result in chemical residues that exceed maximum residue limits, Ms Megirian says.
This, in turn, can lead to the rejection of canola shipments in export markets and create ongoing market access issues.
Following label directions is not only a regulatory requirement, it is also important in preserving haloxyfop herbicide chemistry as a cost-effective grass control option for canola growers across the country.
GRDC Research Code: MCM00003
More information: Gerard McMullen, gerardmcmullen@optusnet.com.au; Georgia Megirian, 08 9230 4600, georgia.megirian@grdc.com.au