- Black Dot (Colletotrichum coccodes)
- External skin blotches and internal stem discolouration.
- Blackleg (Pectobacterium carotovorum)
- Black rotted base of stem.
- Black Scurf (Rhizoctonia solani)
- Black bumps on skin of potato.
- Leafroll (Polerovirus)
- Curled leaves with red or yellowish discolouration.
- Potato Blight (Phytophthora infestans)
- Shrunken and rotten potatoes.