A few roadblocks remain to the commercial introduction of the new ALS-resistant “Inzen” sorghum technology, although a major hurdle has been overcome with the announced 2016 registration approval of “Zest WDG herbicide.” Zest WDG is the dry formulation of the active ingredient nicosulfuron for use on Inzen sorghum hybrids. Inzen sorghum hybrids are being developed by DuPont Pioneer and Advanta. However, no Inzen are currently commercially available to growers yet.
In addition, the Canadian Food Inspection Agency, which regulates the release of Plants with Novel Traits (PNT), has not yet approved this technology. Inzen sorghum and products containing Inzen sorghum fall into this PNT category and must receive approval before Inzen sorghum or products from Inzen sorghum can be exported into Canada. The bottom line is that the timeframe for a full launch of this technology has been delayed by the need for Canadian approval and hybrid development.
The latest word from United Sorghum Checkoff program is that a full launch of Inzen hybrid technology could be 2019 at the earliest, and possibly 2020. No seed company farmer demonstrations will be planted in 2017, but university field trials demonstrating the Inzen grain sorghum technology will continue in 2017.
K-State continues to be active and very successful breeding Inzen sorghum lines with excellent tolerance to nicosulfuron and very good yield potential. Interested sorghum companies can get more information on the availability of these ALS-resistant inbreds by contacting K-State sorghum breeder, Dr. Tesfaye Tesso at firstname.lastname@example.org
Zest WDG herbicide applied postemergence can control volunteer sorghum and small annual grasses such as volunteer wheat, witchgrass, barnyardgrass, foxtails, sandbur, and crabgrass. Unlike glyphosate, Zest WDG must be applied to very small grasses to achieve adequate control. Generally Zest WDG may have limited activity on grassy sandbur, stinkgrass, and crabgrass unless these grasses are very, very small at the time of application. A complete list of grasses controlled and their maximum size for adequate control is provided in the Zest WDG label.
Inzen sorghum technology is the result of a multi-year partnership between Kansas State University and DuPont Crop Protection with support from the Kansas Grain Sorghum Commission, the United Sorghum Checkoff Program, and National Sorghum Producers.
Curtis Thompson, Extension Agronomy State Leader and Weed Management Specialist