By Yeshi Wamishe, Extension Rice Plant Pathologist
Tough season! Some rice planting pulled towards the late-end again in 2020. Generally, late planted rice entertain more diseases than early planted rice. The earlier planted rice sometimes may not be fortunate enough if the weather cooperates with plant pathogens. Currently, sheath blight is bouncing in fields including row rice. There are a few reports of leaf blast. When it comes to the smuts, we cannot visually detect the symptoms ahead of time. By the time we see the symptoms, the damage is already done. Several factors play part in disease prevalence and severity level. Our field management plays the greatest role. Among those seeding heavily and applying nitrogen fertilization excessively make bad disease situation. As a result, use of fungicides to reduce disease pressure becomes inevitable in our rice production adding more money in production cost.
Remember: Well managed fields benefit better from fungicide application. Fields benefit from fungicides applied at recommended timing and rate using adequate volume of water–for areal application 5-7 gal/acre and for ground application up to 10 gal/acre. If less than 5 GPA, better to keep that money! Our research has shown with 3GPA of water, sheath blight was as bad as the unsprayed check. Below is the compositions of active ingredients in commonly used fungicides in Arkansas rice.