Association of 16SrII-C and 16SrII-D subgroup phytoplasma strains with witches' broom disease of Parthenium hysterophorus and insect vector Orosius albicinctus in India

Parthenium weed (Parthenium hysterophorus, Asteraceae) is a common, invasive weed found throughout the Indian subcontinent, Africa, America and Australia. The observed disease, Parthenium Witches' Broom (PWB), characterised by phylloidy, stunting and prolific branching was observed during a field survey conducted between September 2014 to June 2015. PWB phytoplasma was detected in all symptomatic plant samples and in the previously reported insect vector, Orosius albicinctus belonging to family Cicadellidae (subfamily Deltocephalinae) and other Hemipteran insect samples by amplifying its 16S rRNA gene. To our knowledge, this is the first report of a 'Ca. Phytoplasma aurantifolia'-related strains associated with witches' broom disease of P. hysterophorus and insect vector Orosius albicinctus.