Characterization of a Phytoplasma Associated with Frogskin Disease in Cassava.

Cassava frogskin disease (CFSD) is an economically important root disease of cassava (Manihot esculenta) in Colombia and other South American countries, including Brazil, Venezuela, Peru, Costa Rica, and Panama. The roots of severely affected plants are thin, making them unsuitable for consumption. In Colombia, phytoplasma infections were confirmed in 35 of 39 genotypes exhibiting mild or severe CFSD symptoms either by direct or nested polymerase chain reaction (PCR) assays employing ribosomal (r)RNA operon primer pairs.