Sulfur deficiency of rice: The following images show leaf symptoms of sulfur deficiency. We rarely see this in Arkansas and it is usually in patches or areas of fields, often associated with sandy regions but may be reported on “cut” spots as well. In the latter, it may be associated with other deficiencies from what we have observed.
Another view of the tip discoloration and the spotting between veins.
Potassium Deficiency: Many silt loam rice soils in Arkansas are low in available potassium. Rice grown on these soils is subject to potassium deficiency, which often gets noticed during the early to mid booting stages, and to more severe stem rot and brown spot.
You may also notice severe brown spot as above. This often occurs on deficient Bengal and other rice varieties.
If caught in time, nutrient deficiencies may be stopped by the application of “rescue” fertilizer applications but these attempts are too late to prevent yield losses. They may stop progression of the symptoms or help slow diseases a bit. Greater success for salvaging these situations is achieved with early detection.
One of the biggest challenges with potassium deficiency is what is known as “hidden hunger”. This occurs when the plants are slightly deficient in potassium but no visable deficiency symptoms are displayed by the plant. Because of this situation, we strongly recommend adequate soil sampling and application of preplant potassium as recommended. We have observed significant yield increases from potassium from plots exhibiting only mild or no deficiency symptoms until it is too late.