By Damian Jones, ICC
- Marvel and Prosaro improved yields in this trial.
- Grain protein, screenings and retention were not impacted by any of the treatments.
ICC has trialled the use of the PGRs on barley over the last few years with promising but not necessarily consistent results.
Trials conducted in 2012 and 2013 produced yield increases, but this did not occur in 2014, and the yield increases could not be simply explained by reduced lodging.
Similarly, we have seen increased yield with the use of a fungicide early in the season
with no apparent leaf disease.
In 2015 a barley trial was established with Commander barley (S to scald; MS-S to spot form of net blotch) to examine the effect of the PGR trinexapac-ethyl (Moddus or Marvel) as well as a range of fungicides.
The trial was sown on May 26.
All fungicides (Table 1) were applied at second node stage (Z32), with the Tilt Xtra treatment receiving a second application at flag leaf emergence (Z39), done so to continue protecting the whole canopy rather than targeting the flag leaf.
Table 1: Fungicide treatments applied to barley in 2015 fungicide and PGR trial.
No obvious disease was noted on the plants throughout the season.
The PGR treatments were a one and two spray strategy. The one spray strategy consisted of one application of trinexapacethyl (Marvel @ 570 ml/ha) at second node (Z32) stage. The two spray strategy saw an application at second node (Marvel @ 570ml/ha) and again at flag leaf emergence (Z39) (Marvel @ 285 ml/ha).
The second spray was applied to stop ‘bounce back’ or where the crop can compensate under good growing conditions for the earlier PGR application and recover to the
original height of the unsprayed crop.
The trial received four spring irrigations and was harvested on November 27.
Table 2: Yield and quality of barley applied with fungicide or PGR.
Marvel and Prosaro did improve yields above that of the control. The Marvel treatments did have the shortest crop height but not statistically different to the control. On the other
hand, Prosaro did promote extra crop height.
None of the treatments had any effect on protein, screenings or retention.
Once again, the PGR trinexapac-ethyl has shown to produce a yield benefit, and again for no obvious reason. The other interesting result was from the Prosaro – increased
crop height and yield. The diseases controlled are similar to those controlled by Tilt Xtra so it is unlikely that disease was the reason for the result, as even if Prosaro had a longer protective period, disease pressure was minimal.
The increased height is also a mystery as Prosaro can be used as a PGR at higher rates.
The stubble project – maintaining profitable farming systems in Victoria and Tasmania with retained stubble (project number BWD00024) is funded by the GRDC.
A printer-friendly version of this research report is available here.