Identification symptoms
1. The disease affects the crop at all stages. The earliest symptoms appear on the seedlings in the cotyledons which turn yellow and then brown.
2. The base of petiole shows brown ring, followed by wilting and drying of the seedlings.
3. In young and grown up plants, the first symptom is yellowing of edges of leaves and area around the veins, i.e. Discolouration starts from the margin and spreads towards the midrib.
4. The leaves loose their turgidity, gradually turn brown, droop and finally drop off.
5. Browning or blackening of vascular tissues is the other important symptom, black streaks or stripes may be seen extending upwards to the branches and downwards to lateral roots.
6. The plants affected later in the season are stunted with fewer bolls which are very small and open prematurely