Association of different groups of phytoplasma in flower malformation, phyllody, foliar yellowing, and little leaf disease of rose (Rosa sp.)

ABSTRACTAn extensive survey on rose cultivars in New Delhi showed phytoplasma-suspected symptoms such as leaf chlorosis, phyllody, virescence, and little leaf in 35 rose cultivars. Vegetative propagation through stem and tissue culture was performed. The cuttings/budded plants raised from infected plants showed the symptoms of phytoplasma disease. Phytoplasma was detected in 13 symptomatic plants using nested polymerase chain reaction (PCR) with phytoplasma-specific primer pairs P1/P7 and R16F2n/R16R2. Nested PCR amplicons from the 13 most severely infected rose cultivars (Arunima, Sindoor, Taboo, Sunsation, Raktgandha, Jawahar, Surkhab, Pusa arun, Marco Polo, Perfume de French Comete, Green Rose, Snowfire, and Gladiator) were cloned and sequenced. BLASTn analysis of 16S rRNA gene sequences, virtual RFLP and phylogenetic analysis revealed that the phytoplasma sequences amplified from rose belonged to ‘Candidatus Phytoplasma asteris’ subgroup 16SrI-B and ‘Ca. P. australasia’ subgroup 16Sr II-D. Our results...