First report of the presence of the lethal yellowing group (16Sr IV) of phytoplasmas in the weeds Emilia fosbergii and Synedrella nodiflora in Jamaica

Abstract

Bermuda grass showing symptoms of white leaf disease has been observed in the area of Rajasthan, India. The diseased plants showed typical white leaf symptoms, proliferation of auxiliary shoots, bushy growing habit, small leaves and shortened stolons. Using polymerase chain reaction (PCR) amplification with P1/P6 universal primer followed by R16F2n/R16R2 primers, all symptomatic plants tested positively,. whereas no amplification product was obtained from non-symptomatic plants. RFLP analysis of PCR products with HaeIII, RsaI or AluI endonuclease generated fragment profiles that were identical for all white leaf samples. The phytoplasma 16/23S intergenic region was sequenced directly with primers R16F2n/R16R2 and compared by BLAST analysis with those of other phytoplasma rDNA sequences archived in GenBank. The highest sequence homology (95%) obtained was with that of 'Candidatus Phytoplasma cynodontis' (GenBank Accession No.Y14645), the type member of the BGWL (16SrXIV) group. This is the first molecular identification of 'Ca. Phytoplasma cynodontis' (16SrXIV group) associated with Bermuda grass white leaf disease in West India (Rajasthan).