Genetic diversity of phytoplasmas associated with several bamboo species in India

Symptoms of phytoplasma diseases, including witches' brooms, shoot proliferation, little leaf, yellowing and decline were observed in eleven species of bamboos in eight states of India. Symptomatic bamboo samples were indexed for phytoplasma presence using universal phytoplasma-specific 16S rRNA gene primer pairs. Sequence comparison analysis and virtual RFLP analysis of 16S rRNA sequences indicated that the symptomatic bamboo samples of Dendrocalamus asper, Dendrocalamus strictus and Pseudoxytenanthera stocksii from Tripura, Uttar Pradesh, Uttarakhand and New Delhi and Bambusa bambos, Bambusa nutans, Bambusa pallida, Bambusa tulda, Dendrocalamus hamiltonia and D. strictus from Karnataka were infected with 'Candidatus Phytoplasma australasia'-related strains (16SrII-C or 16SrII-D); Bambusa vulgaris, D. asper and P. stocksii from Karnataka were positive for 'Ca. P. asteris' strains (16SrI-B), and one phytoplasma in B. nutans from Sikkim was identified as 'Ca. P. cynodontis' strain (16SrXIV-A). Weeds and leafhoppers from the vicinity of bamboo plantations were also tested, and 16SrII group of phytoplasmas was identified in eight symptomatic weed species (Ageratum conyzoides, Cannabis sativa, Cleome viscosa, Datura stramonium, Parthenium hysterophorus, Ocimum canum, Phyllanthus niruri and Tephrosia purpurea) from five different states and one leafhopper species (Mukaria spledida) from three states. These results suggest that wide genetic diversity of phytoplasma exists in various bamboo species in different states of India. The report of 16SrI-B, 16SrII-D and 16SrXIV-A subgroups of phytoplasmas infecting eight bamboo species except D. strictus are the first records in the world.