L. R. Brown et al. / Agricultural Sciences 3 (2012) 755-758
(20%). Saflufenacil caused 11% (25 and 50 g a.i. ha−1),
18% (100 g a.i. ha−1) and 20% (200 g a.i. ha−1) injury in
May of the following spring in winter wheat with the
greatest injury occurring with the POST (16%) and
POST + Merge (41%) applications (Table 3). As the
season progressed into July, there was little to no injury
from saflufenacil application the previous autumn.
There was no effect of saflufenacil on winter wheat
height or yield (Table 3). Even though saflufenacil ap-
plied POST and POST + Merge caused up to 16% and
41% injury respectively, this injury was transient with no
effect on winter wheat height or yield. These results dif-
fer from studies conducted by Knezevic et al.  who
reported a significant yield reduction (up to 66%) with
autumn POST applications of saflufenacil and up to 67%
with spring POST applications in winter wheat.
This study concludes that there is an acceptable mar-
gin of crop safety in winter wheat to PP and PRE appli-
cations of saflufenacil. The POST applications caused
injury that would be unacceptable to growers even
though in this study it did not result in a yield loss. There
was greater injury when saflufenacil was applied POST +
Merge. Injury was the greatest at higher doses. Since this
research has shown that saflufenacil can be applied
safely to winter wheat either PP or PRE future research
should focus on the control of winter annual, biennial
and perennial broadleaf weeds. The autumn application
of saflufenacil may eliminate the need for spring applied
herbicides for broadleaf weed control.
The authors would like to acknowledge Todd Cowan for his exper-
tise and technical assistance in these studies. Funding for this project
was provided in part by the Grain Farmers of Ontario (GFO) and
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