Canola Pre-emergent Trial

How does the overall efficacy & crop safety of Butisan, Altiplano and D500 compare with propyzamide and trifluralin - targeting annual ryegrass.

Dumbleyung, WA, 2017

Summary

This trial was established near Dumbleyung, Western Australia to compare and demonstrate to the extended David Gray network the efficacy and crop safety of three new Canola pre-emergent herbicides vs. the district standard propyzamide and trifluralin. The target weed was annual ryegrass (ARG).

The dry start to the season meant that the pre-ems ran out of activity before the main germination of ARG. This meant that the early ARG population was low and uneven making assessments difficult.

Butisan was the top performer with ~60% control, closely followed by Propyzamide, Altiplano, D500 and trifluralin in that order. Transient bleaching of canola in the Altiplano plots was observed with no crop damage or herbage reduction observed in any of the other treatments. 

Methodology

Treatment List

Tmt No.ProductRate AI Rate (gai/ha)1Untreated--2Butisan1.8L9003Altiplano + trifluralin3Kg + 1L1200 + 105 + 4804Altiplano3kg1200 + 1055D5002.5Kg-6Trifluralin2L980

Trial Layout

Experimental Design

Design:Commercial DemonstrationReplications:2Plot length:40mPlot Width:4m

Site, Crop and Application Details

Assessment Methods

Assessment Date:Assessment22/05/2017Visual inspection (28 DAT)09/06/2017Observations (42 DAT)26/06/2017Control ratings (56 DAT)

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

Observations (28 DAT) – Kim Gooding

• 1st rain just received at 25 DAS. 42 DAS will be the first proper measure as no ARG germinated yet.
• Some Canola up but sparse.
• Untreated plots still clean

Observations (42 DAT) – Kim Gooding

• 1.8L Butisan - very good on all grasses. Canola Healthy.
• 560g Rustler - very good against ARG. Barley grass present.
• 3Kg Altiplano + 1L Trifluralin – ARG present in furrow in low numbers. Barley grass highly present. Uneven discolouration on canola plants. Yellow bleaching on margins + whole leaves. 
• D500 – ARG more present + high big ARG numbers. Canola healthy.
• Trifluralin – Even barley grass + large in furrow ARG. Canola healthy.

Control Ratings (56 DAT)

The least significant difference (LSD) for these ratings is 5.17, hence there is no statistical difference between treatments. However there are slight numerical differences with Butisan the top performer and trifluralin the worst.  A rating of 10 is 100% control, 5 means half the number of weeds present compared with untreated and 0 means no different to untreated.

Conclusion

Pre-emergent herbicides as a whole struggled with dry conditions (pre & post sowing) in 2017. With a staggered and late germination of ARG assessments proved very difficult. Weed counts could not be achieved in a representative/accurate way and thus we only managed to get observational ratings. Even then it was difficult to walk from plot to plot and accurately estimate the % control as the germination of ARG was very patchy. Therefore the above ratings are very subjective and must be interpreted with caution. 

To achieve the above ratings we walked the length of each plot and tried to rate its control vs. the untreated. We did this without knowing what each plot had been treated with and over two replications and then averaged the results. 

Appendices 

Rainfall

 Photos

Follow the below link for photos:

https://www.dropbox.com/sh/zux4gpcsd8nqkm2/AADhlcFXbFjVfQMwG7-XiIcOa?dl=0