Symptoms
- dark brown necrotic spots appear first on the tip of older leaves,then along the edge,and finally on the leaf base.
- Upper leaves short,droopy,and dark green.
- Lower leaves may bend downward.
- Early leaf senscence,leaf wilting,and leaf rolling when temperature is high and humidity is low.
- Increased incidence of diseases.(Leaf symptomps of K deficiency,particularly the yellowish brown leaf margins,are similar to those of tungro virus disease.Unlike K deficiency,tungro occurs as patches within a field,affecting single hills rather than the whole field.)