Detection and characterization of the phytoplasma associated with a phyllody disease of black pepper (Piper nigrum L.) in India

Using polymerase chain reaction (PCR), the phytoplasma was detected in black pepper (Piper nigrum) with phyllody symptoms in India. A 1.20 kb DNA fragment encoding the portion of phytoplasma 16S rDNA consistently amplified by nested PCR was cloned and sequenced. The sequenced region contained 1230 nucleotides. Sequence analyses showed that the gene was most closely related to members of aster yellows group (16Sr I) of phytoplasma. The sequence identity with members of aster yellows group (16Sr I) was >98% while that with members of other groups (16Sr II to 16Sr XV and other undesignated groups) ranged from 87 to 96%. On the basis of sequence identity and phylogenetic relationship studies, it is concluded that phytoplasma infecting black pepper in India belongs to aster yellows group. This is the first report of identification of phytoplasma in black pepper.