GCS Azoxyprop vs Tar Spot

Tar spot has been confirmed in six states in 2024 by University Extension professionals as of this writing. You can track these confirmed #tarspot sightings on a county-level basis at https://corn.ipmpipe.org/tarspot/. Data shows that #fungicide applications containing at least 2 modes of action can significantly help manage tar spot severity and protect yield [1], including the two modes of action in GCS Azoxyprop - azoxystrobin and propiconazole. The best time to apply a fungicide for tar spot management is between VT and R3 [2].

GCS Azoxyprop is an effective fungicide against common corn diseases, and labeled for use against northern corn leaf blight, gray leaf spot, and southern rust, among others. The label does not make recommendations for use against tar spot, but studies show that these chemistries work against tar spot. In cases like this, the EPA allows its use against the disease through a FIFRA Section 2(ee) Recommendation. Recently, many states with a history of tar spot outbreaks have accepted this recommendation, and GCS Azoxyprop is now another viable option that growers can use to manage tar spot. In a low priced commodity market, these types of affordable and effective fungicides are an important option for farmers to have. The 2(ee) label is available to use in the following states for their corn growers: DE, GA, IL, IN, IA, KS, KY, MD, MI, MN, MO, NE, ND, OH, PA, SD, TN, & WI.

To learn more about #tarspot check out the FBN Pest Page: https://www.fbn.com/direct/pest/tar-leaf-spot. If you’re interested in using GCS Azoxyprop for your tar spot management this year, you can find product and price details at the FBN Product Page: https://www.fbn.com/direct/product/gcs-azoxyprop

Sources

[1] Telenko et al. 2022, https://apsjournals.apsnet.org/doi/epdf/10.1094/PHP-10-21-0125-RS

[2] Ross et al. 2024, https://apsjournals.apsnet.org/doi/epdf/10.1094/PDIS-05-23-0932-RE