By Ron Baker and Ralph Mazzanti, Rice Research Verification Program Coordinators
South Arkansas: With the substantial increase in heat units the last few weeks the fields are ahead of their DD50 predictions. The Lincoln Co. row water field was one of the earliest to head causing stink bugs to reach threshold levels triggering an application. The Arkansas Co. field is 100% heading and unless stink bugs disperse by Monday it will also receive an application. The Jefferson Co. field stink bug numbers are running 3-4 per 10 sweeps. The Desha Co. field is right at threshold and we will sweep again early next week to determine an application. The Desha Co. field which is a blast-susceptible variety is threatened by neck and or collar blast lesions in neighboring fields. A one-time fungicide application is warranted at this time while main tillers are at the 50-75% heading but while the neck is still in the boot. The Phillips Co. field received a midseason fertilizer application.
North Arkansas: Most fields are now ahead of their DD50 predictions and are heading in advance of expected dates. Rice stink bugs were found in large numbers in the River Valley. Conway Co., being one of the earlier fields to head in the area, had numbers that were multiple times the threshold for treatment. This large population quickly overwhelmed natural predators and triggered an insecticide application. Disease pressure remains light but Sheath Blight has been detected in a few fields. Jackson Co. required a fungicide treatment for the disease but only on one edge of the field where the rice was planted too thickly the first round of the grain drill. The remainder of the field has outrun the disease. No pesticide treatments were recommended for other fields but that is likely to change soon.
For field-specific information, please see linked pdf below.