Herbicide-resistance traits have created additional weed control options in alfalfa, canola, corn, soybeans, sugarbeets, sunflowers and wheat. However, traits may create confusion surrounding which herbicides can be applied safely and legally to the various crop trait packages. Misapplication due to confusion can be very costly and embarrassing for the producer and collaborating partners.
Weed management to prevent herbicide-resistant weeds requires a well-developed strategy. A durable weed management strategy considers the crops planned for the field and chemical, cultural and mechanical control strategies to achieve excellent control of the primary weeds in the field. Your weed management strategy should consider herbicide applied in sequence and mixtures, along with nonchemical control options, to preserve the value of herbicides and herbicide-resistant traits on your farm.
Reading and following label guidelines when applying herbicides to any crop is important. The label of some glyphosate products indicates they can be applied to Roundup Ready® and glyphosate-tolerant crops. Most glyphosate labels state the products are for use in Roundup Ready® crops or in crops that have the Roundup Ready® gene. Other glyphosate labels have language stating the glyphosate product can be applied to glyphosate-tolerant crops.
This reference guide is designed to help clarify which herbicide products can be applied to various trait packages. You always should verify seed tags and herbicide labels to ensure misapplication does not occur.
Table 1. Alfalfa herbicide-resistant traits and herbicides that can be used in combination with resistant traits. A checkmark indicates that alfalfa herbicide trait packages have resistance to various herbicide products (a).Alfalfa Herbicide Trait | Glyphosate | Glufosinate | Growth Regulators |
---|
Conventional | | | |
Roundup Ready Alfalfab | ✔ | | |
aAlways consult herbicide labels for application requirements.
bAlways consult herbicide label to determine if glyphosate formulation is approved for RR alfalfa.
Table 2. Canola herbicide-resistant traits and herbicides that can be used in combination with resistant traits. A checkmark indicates that canola herbicide trait packages have resistance to various herbicide products (a).Canola Herbicide Trait | Glyphosate | Glufosinate | ALS Inhibitors |
---|
Conventional | | | |
Roundup Ready | ✔ | | |
Roundup Ready TruFlex | ✔ | | |
LibertyLink | | ✔ | |
TruFlex LibertyLink | ✔ | ✔ | |
Clearfield Canolab | | | ✔ |
SU Canolac | | | ✔ |
aAlways consult herbicide labels for application requirements.
bApply Beyond/Beyond Xtra (imazamox) to Clearfield canola varieties.
cApply Draft (thifensulfuron and triberuron) to SU Canola varieties
Table 3. Corn herbicide-resistant traits and herbicides that can be used in combination with resistant traits (a). A checkmark indicates that corn herbicide trait packages have resistance to various herbicide products (b).Corn Herbicide Trait | Glyphosate | Glufosinate | 2,4-D Cholinec | FOP ACCase Inhibitorsd |
---|
Conventional | | | | |
Glyphosate Tolerant (GT) | ✔ | | | |
LibertyLink (LL) | | ✔ | | |
GT LL | ✔ | ✔ | | |
Roundup Ready 2 Yield (RR2Y) | ✔ | | | |
RR2Y LLe | ✔ | ✔ | | |
Enlist | ✔ | | ✔ | ✔ |
aTrait names often refer to insect resistance traits (Agrisure, Optimum, Yieldgard, etc.). Be sure to consult seed tags and product information to ensure herbicide trait packages.
bAlways consult herbicide labels for application requirements.
c2,4-D is labeled for corn. Only approved 2,4-D choline formulations are permitted for applications to Enlist corn (Enlist Duo, Enlist One) at higher rates or later stages of corn growth.
dAssure II only and not other FOP or ACCase inhibitors.
eAlways consult herbicide label to determine if glyphosate formulation is approved for RR corn.
Table 4. Soybean herbicide-resistance traits and herbicides that can be used in combination with resistant traits. A checkmark indicates that soybean herbicide trait packages have resistance to various herbicide products (a).Soybean Herbicide Trait | Glyphosate | Glufosinate | 2,4-D Cholineb | Dicambac | HPPD Inhibitorsd |
---|
Conventional | | | | | |
Glyphosate Tolerant (GT) | ✔ | | | | |
Roundup Readye | ✔ | | | | |
Roundup Ready 2 Yielde | ✔ | | | | |
Roundup Ready 2 Yield Xtende | ✔ | | | ✔ | |
Roundup Ready 2 Yield Xtendflexf | ✔ | ✔ | | ✔ | |
LibertyLink (LL) | | ✔ | | | |
LLGT27d | ✔ | ✔ | | | ✔ |
Enlist | ✔ | | ✔ | | |
Enlist E3 | ✔ | ✔ | ✔ | | |
GT27 | ✔ | | | | ✔ |
aAlways consult herbicide labels for application requirements.
bOnly approved 2,4-D choline formulations (Enlist Duo, Enlist One) are permitted for over-the top applications to Enlist and Enlist E3 soybeans.
cOnly approved dicamba formulations (Engenia, FeXapan, Tavium, XtendiMax) are permitted for over-the-top application to Xtend and XtendFlex soybeans.
dMotif is UPL’s mesotrione that is labeled for mesotrione-tolerant soybeans. The label is pretty vague and generic, but pretty sure it is labeled for all GT27 soybeans. Other mesotrione’s might have this new label too.
eAlways consult herbicide label to determine if glyphosate formulation is approved for RR soybeans.
fNot approved for commercial production in the U.S. as of January 2021.
Table 5. Sugarbeet herbicide-resistant traits and herbicides that can be used in combination with resistant traits. A checkmark indicates that sugarbeet herbicide trait packages have resistance to various herbicide products (a).Sugarbeet Herbicide Trait | Glyphosate | Glufosinate | Growth Regulators |
---|
Conventional | | | |
Roundup Readyb | ✔ | | |
aAlways consult herbicide labels for application requirements.
bAlways consult herbicide label to determine if glyphosate formulation is approved for RR sugarbeets.
Table 6. Sunflower herbicide-resistant traits and herbicides that can be used in combination with resistant traits. A checkmark indicates that sunflower herbicide trait packages have resistance to various herbicide products (a).Sunflower Herbicide Trait | Glyphosate | Glufosinate | ALS Inhibitors |
---|
Conventional | | | |
Clearfield Sunflowerb | | | ✔ |
Clearfield Plus Sunflowerb | | | ✔ |
Express Sun Sunflowerc | | | ✔ |
aAlways consult herbicide labels for application requirements.
bApply Beyond/Beyond Xtra (imazamox) to Clearfield wheat varieties.
cApply Express SG (tribenuron) to Express Sun sunflower varieties.
Table 7. Wheat herbicide-resistant traits and herbicides that can be used in combination with resistant traits. A checkmark indicates that wheat herbicide trait packages have resistance to various herbicide products (a).Wheat Herbicide Trait | Glyphosate | Glufosinate | ALS Inhibitors | FOP ACCase Inhibitorsc
|
---|
Conventional | | | | |
Clearfield Wheatb | | | ✔ | |
Clearfield Plus Wheatb | | | ✔ | |
CoAXium Wheat | | | | ✔ |
aAlways consult herbicide labels for application requirements.
bApply Beyond/Beyond Xtra (imazamox) to Clearfield wheat varieties.
*This publication is adapted from Butts et al. 2019. Herbicide resistance traits: quick reference guide. MP544. Available at www.uaex.edu/publications/PDF/MP544.pdf