By Yeshi Wamishe, Extension Rice Pathologist
As rice plants get to maturity, different kinds of discolorations can be seen in some fields on glumes. Discolorations are worse in glumes that are blank. Panicle blanking can be caused by different biotic and abiotic factors. In some circumstances up to 5% grain blanking across a panicle can often be seen. Lower or higher, the glumes with no developing seed start dying and as a result, saprophytic fungi and bacteria grow on them rendering various kinds of discolorations. Pictures below show a few examples of panicle/glume discolorations in rice fields caused by biotic factors. Florets discolorations are often severe under heavy dew or rain and if harvest is excessively delayed.