An outbreak of leaf blast occurred on more than 200 acres of commercial rice fields in Winnie, Chambers County, Texas. The affected variety was medium-grain Jupiter at the boot stage. Jupiter is one of the most susceptible varieties. The outbreaks of rice blast on this variety also have been reported in at least seven counties in Arkansas.
In addition, an outbreak of leaf and neck blast also occurred in the Italian semifino variety Vialone Nano in China, Jefferson County, Texas. Weather conditions for the past weeks appeared to be conducive for the development of leaf and neck blast.
Rice blast is very explosive and can destroy a crop within a short period of time under most favorable conditions. The spores of the rice blast pathogen are wind-borne and can spread over long distances.
Timely and proper management of rice blast is the key to minimizing yield and quality losses caused by this devastating disease:
- Scout fields for the presence of leaf blast at least weekly until the heading stage.
- Maintain a 4-to-6-inch continuous flood to reduce the damage caused by this disease.
- Carefully time fungicide applications. If a single fungicide application is needed, the application should be made at the heading stage (50% to 70% heads emerging from the boot). If 2 applications are needed because of severe disease pressure, the first application should be made at boot (2-4 inch panicle), followed by the second application at heading (no later than 70% heads emerging from the boot). Trifloxystrobin-containing fungicides (Stratego, 16-19 oz/A; and Gem, 3.1-4.7 oz/A) are most effective.
For more information about rice blast disease and its management, please visit the 2014 Texas Rice Production Guidelines.
If you suspect blast in your fields and need more information about blast management, you also can contact Dr. Shane Zhou at firstname.lastname@example.org or (409) 752 2741 ext. 2225.