Welcome to the latest NGA newsletter and a snapshot of our planned trials for Summer 2013/14.
Our winter program is well advanced with most trials in good condition despite the difficult weather conditions in recent months. The summer program is heavily focused on weed management but with a continuation of the root-lesion nematode ‘resistance evaluation’ in summer crop varieties, that commenced in 2012/13.
We have recently closed our 2013 survey on the topic of Fallow Management of Summer Grass Weeds. We had over 90 surveys submitted with responses from nearly 60% of the target audience - a fantastic response. A brief article at the bottom of this newsletter features the results from the question exploring glyphosate resistance levels in awnless barnyard grass.
Once again, if you have any feedback (positive or negative) we would be glad to hear from you.
Summer 2013/14 Trial Snapshots
Project 1. Residual Herbicides in the Summer Fallow
A major focus of our program this summer with a total of fifteen trials evaluating residual control of key summer grass weeds. Six trials target the control of awnless barnyard grass (ABYG), five trials evaluating feathertop Rhodes grass (FTR) management with two trials each against windmill grass and liverseed grass.
Project 2. Knockdown Trials on Summer Grasses
Four trials are planned to evaluate a range of management options for glyphosate resistant ABYG with three trials on FTR. Treatments will be compared with or without a double-knock treatment of paraquat.
Project 3. Root-lesion Nematode Resistance
Collaborative work with seed companies and breeders to evaluate the impact of summer crop varieties on root-lesion nematode populations. Potential trials in sorghum, dryland cotton, corn, sunflower and mungbeans.
Project 4. Fleabane Control
Evaluation of herbicide options for controlling large fleabane in the summer fallow. Six trials evaluating phenoxy and non-phenoxy options with or without double-knock.
Project 5. Common Sowthistle Control
Three trials planned on large flowering sowthistle, particularly in response to issues from the Liverpool Plains. Treatments include glyphosate with a range of mixing partners together with double-knock approaches.
Project 6. Mungbean Herbicide Screen
Three trials examining the crop safety of herbicides with potential for registration in mungbeans. Trials include a refined list of herbicides that were screened in 2011/12 or 2012/13.
Project 7. Gp A Plantbacks
NGA trials will focus on winter cereal safety with application of five herbicides at three intervals prior to planting. Intention is to plant trials with commercial disc planters to maximise the crop safety risk. Additional detailed trials are being planned by the Northern Weeds team for 2014/15.
Project 8. Volunteer Canola Control
Three trials comparing a wide range of glyphosate mixing partners. Particularly focussed at non-phenoxy herbicide options.
Project 9. Scurvy Weed Control
Three trials comparing a range of residual herbicide options for scurvy weed management benchmarked against the most consistent knockdown approaches.
Project 10. Cotton Cut-stump
Three trials planned as a follow up to screening in 2012/13. Treatment list will be heavily dependent on final results from trials established in autumn 2013.
SURVEY: Glyphosate Resistant Awnless Barnyard Grass - A Rapidly Escalating Regional Threat
One of the questions in our recent survey aimed to determine the extent of suspected or confirmed glyphosate resistance in awnless barnyard grass. The graph below shows the responses from 82 growers and advisers when asked to:
"Please estimate the % of your FALLOW PADDOCKS with awnless barnyard grass in the following three categories"
41 of the 82 growers and advisers surveyed, indicated that they had ABYG with suspected glyphosate resistance in more than 10% of their fallow paddocks
Awnless barnyard grass management must change from relying on glyphosate dominant approaches or we risk losing this herbicide completely.