Barley Fungicide Post Trial

How does the efficacy of Aviator Xpro, Ceriax, Opera, Amistar Xtra, Avior Gold and Legend compare with the Cogito against various foliar diseases in barley.

Dumbleyung, WA, 2017

Summary

This trial was established near Dumbleyung, Western Australia to compare and demonstrate to the David Gray’s extended network the efficacy of various SDHI and azole fungicides compared with the regional standard – Cogito.

In this trial La Trobe barley was sown into 3 years of Bass barley stubble. Due to seasonal conditions disease pressure was relatively low with only spot and net form of blotch present. Half the trial had a single spray of premiums at Z34 and the other half had the premiums at Z34 followed by 500ml/Ha of Opera at Z41-45. (See diagram below) This was done to try and compare the benefits of a double spray strategy vs a single spray strategy. All treatments significantly reduced the disease incidence with Ceriax and Aviator Xpro leading the pack at both assessment dates. Legend is a powdery mildew product but unfortunately no powdery made an appearance. Visually it compared with the Cogito treatment which is what we would expect. Cogito performed very well in this trial.

Methodology

Treatment List

Tmt No.ProductRate (mL/ha)AI Rate (gai/ha)1Untreated--2Cogito25062.5 + 62.53Opera50042.5 + 31.254Ceriax75031.2 + 50 + 31.25Aviator Xpro30045 + 22.56Amistar Xtra40080 + 327Legend + Cogito300 + 25075 + 62.5 + 62.58Avior Gold31337.56 + 31.3

Trial Layout

Experimental Design

Design:Commercial DemonstrationReplications:2Plot length:30mPlot Width:4m

Site, Crop and Application Details

Assessment Methods

Assessment Date:Assessment25/07/2017Photographs Pre-Spray23/08/2017Disease Assessment (28 DAT)08/09/2017Disease Assessment (42 DAT)20/11/2017Yield

Data Analysis

All data analysis in this report was conducted using Microsoft Excel. Simple means, analysis of variance and the student t-test were used to determine statistical significance using the least significant difference method with a 95% confidence interval.

Results

28 DAT

Focusing on the third youngest leaf ratings, there was very good control in all treatments except in the Opera treatment. However Ceriax maintained good control across all three leaves and was the top performer at this rating.

42 DAT

At 42 DAT the disease started to express in the untreated. Ceriax, Cogito and Aviator Xpro maintained very good control while Opera, Amistar Xtra and Avior Gold begun to lose activity.

Overall Control (42 DAT)

As a % control Ceriax was the top performer with 87% control, closely followed by Cogito, Aviator Xpro and Legend.

Yield

Below are the yield results for two replications of a single spray strategy of premiums at Z34 crop stage. The data has a least significant difference (LSD) of 609Kg. The Ceriax, Cogito, Opera, Legend and Avior Gold treatments yielded significantly (statistically) more than the untreated while Ceriax also yielded significantly more than Amistar Xtra. There is no significant difference between Aviator Xpro and any of the other treatments.

Below are the yield results for a double spray strategy, which received an application of premiums at Z34 followed by and application of 500 mL/Ha of Opera at Z49. The LSD for this data set is 360Kg hence Cogito, Opera and Aviator yielded significantly (statistically) more than the untreated in a double spray strategy. Note the untreated received 500 mL/Ha of Opera at Z49. The message to take home here is early timing of application is key to disease control and consequent yield gain.

Protein

The protein response from a single fungicide application showed no statistical increase in protein. There seems to be no trend either. The same can be said for the double spray strategy.

Return on Investment (ROI)

Taking into account the cost of chemical and the operational costs of applying the fungicide, we did a simple ROI analysis and all treatments returned a positive ROI. Ceriax bringing the largest gain of $192.

Conclusion

In this trial all fungicide treatments resulted in a yield gain ranging from 200 Kg to 900 Kg. Well and truly paying for the application. Ceriax had the highest ROI of $192/Ha and Amistar Xtra bringing the lowest ROI of $29/Ha.

At 28 DAT there were very little visual differences between treatments. However at 42 DAT Aviator Xpro and Ceriax were very clean, closely followed by Cogito. Amistar Xtra, Avior Gold and Opera seemed to have run out of activity and disease started to progress. (Look at 42 DAT photos below – for full scale/quality photos follow the dropbox link on the last page)

There was a visual improvement in the double spray strategy vs the single spray strategy. However yield benefit varied from product to product. This trial had two replications only and thus is prone to variations in soil, elevation and pest hot spots. Therefore the yield data in this trial must be interpreted with caution.