Symptoms on Potato

• Organs attacked  :

• Symptoms :
  • Rather slow plant growth, with an upright habit and many small stems.
  • Deformed and discolored leaves: smaller, rolled up, rather yellow (figures 1 and 2), sometimes purplish (anthocyanin) at the ends of the shoots.
  • Wilting of plants in dry weather.
  • Presence of tubers (figure 3) and aerial stolons.
  • Tubers soft, later rotting during storage.

• >>> More pictures

• Signs  : no visible signs, confirm the possible presence of vectors.
• Possible confusion : phytotoxicity , nutritional disorder, asphyxiation , etc. Note that Rhizoctonia solani also causes aerial tuberization.

• Production areas affected :

• Phytoplasmas reported on potato : 
  • Candidatus phytoplasma australiense (16SrXII-B)
  • Candidatus Phytoplasma solani (16SrXII-A)
  • Candidate Phytoplasma Asteris (16SrI-B)
  • Candidatus Phytoplasma Americanum (16SrXVIII)
  • Candidatus  Phytoplasma (16SrXIII - Mexican periwinkle virescence group)
  • Candidatus  Phytoplasma (16SrII - peanut witches-broom)
  • Candidatus Phytoplasma (16SrIII - X-disease)
  • Candidatus  Phytoplasma (16SrVI - clover proliferation)
  • Candidatus  Phytoplasma (16SrX - apple proliferation)