Molecular and biologic characterization of a phytoplasma associated with Brassica campestris phyllody disease in Punjab province, Pakistan

A phytoplasma-associated disease was iden-tified in Brassica campestris (sarson) plants during a survey conducted in Punjab province of Pakistan in 2014–2016. The symptomatic plants showed character-istic symptoms of phyllody and witches’ broom. Phytoplasma presence was detected by polymerase chain reaction on 16S ribosomal and tuf DNAs, follow-ed by RFLP analysis and sequence comparison of the 16S rRNA and tuf genes. The phytoplasma detected was classified in a new ribosomal subgroup designed 16SrIX-H. The phytoplasma presence in phloem tissues of symptomatic sarson samples was also confirmed through light microscopy and transmission studies to healthy plants through dodder and the leafhopper Orosius albicinctus. This is the first report of identifica-tion of 16SrIX-H subgroup phytoplasma associated with sarson and its natural vector in Pakistan.