Onion Basal Rot: Fusarium oxysporum f.sp. cepae
Symptom:
- The leaves turn yellow and then dry up slowly.
- The affected plant shows drying of leaf tip downwards.
- The entire plant shows complete drying of the foliage.
- The bulb of the affected plant shows soft rotting and the roots get rotted.
- There will be a whitish mouldy growth on the scale.
- This disease can begin in the field and continue on in storage.
Identification of pathogen:
- The fungus produces many chlamydospores which are thick walled resting spores and microconidia which are one celled and thin walled.
Management:
- Growers must follow crop rotation and harvested bulbs must be thoroughly cured to reduce potential storage losses.
- Onions are very sensitive to low soil copper levels. In order to optimize crop production and disease susceptibility, additional soil copper fertility may be needed especially on mucky and sandy soils.
- Soil drenching with Copper oxychloride 0.25 %.
Source-
- TamilNadu Agritech Portal
