Identification and characterization of a phytoplasma disease of jute (Corchorus olitorius L.) from south-western Turkey

Abstract

A phytoplasma disease was detected in naturally occurring jute (Corchorus olitorius L.) plants in an experimental sesame field at the Akdeniz University campus, Antalya, Turkey during the growth periods of 2011 and 2012. Infected plants showed symptoms of phyllody, abnormal development of flowers, yellowing, reduced leaf size and short internodes. DNA extractions were made from symptomatic and symptomless plants' root and leaf tissues. Direct PCR assays with P1/P7 universal phytoplasma primers detected a 1.8 kb product and a 1.2 kb product was obtained using R16F2n/R16R2 primers with nested PCR. Phytoplasmas were detected from all symptomatic plants as well as off-season three dry leafless jute plants collected in 2012. DNA extracted from roots rather than leaf tissues showed better amplification in direct PCR assays. Three samples were cloned and their F2nR2 region was sequenced for identification. Jute phytoplasmas were clustered with the 16SrII (Peanut witches’-broom) group members in BLAST search. For subgroup characterization, virtual RFLP profiles were generated in iPhyclassifier program. As a result, phytoplasmas were identified as related strains of the 16Sr II-D reference strain, ‘Candidatus Phytoplasma australasia’ (Y10097). Actual RFLP profiles obtained with AluI, RsaI, MseI, TaqI enzymes, revealed a similar pattern with virtual RFLP confirming subgroup characterization. In our previous findings, phyllody phytoplasmas infecting sesame plants in this experimental field were classified in the 16SrII-D subgroup. This study shows that phytoplasmas infecting jute and sesame plants were identified in the same phytoplasma group and naturally grown jute plants could possibly serve as inoculum source for next year infections for phyllody disease in sesame. To our knowledge this is the first report of molecular detection of a phytoplasma disease infecting jute in Turkey.