Diagnostic characters for visual diagnosis
- Orange brown superficial discoloration, irregular in shape.
- Lesions have a distinct but irregular margin.
- Individual lesions may extend up to half of the tuber
- Lesions occur more frequently on the underside of tubers in the furrow
- Symptoms are normally present at harvest and do not develop further
- No fungal structures are associated with lesions
Notes on confirmatory diagnostics
- As a non-pathological disorder, no pathogens can be observed associated with lesions even after incubation
- Equally, attempts to isolate from lesions onto agar fails to produce a recognised pathogen
Hide et al (1994). Annals of Applied Biology, 124,253- 265
Hide et al (1994). Potato Research 37, 169-172.
Possible confusing symptoms :