Molecular identification of 16srii-d phytoplasmas infecting Crossandra infundibuliformis in India

Abstract

The symptoms of little leaf, leaf curling, malformed inflorescences, yellowing, and stunting were observed in Crossandra infundibuliformis plants during a field inspection in Mysuru district, Karnataka state, India. The disease incidence ranged from 0.2 to 4%. The DNA extracted from the leaf midrib tissues of symptomatic samples was amplified in polymerase chain reaction assays using 16S rRNA and protein translocase secA genes primers confirming the presence of these bacteria in the symptomatic plants. The nucleotide sequence analysis and the phylogenetic comparison indicated the presence of a ‘Candidatus Phytoplasma australasia’-related strain. The virtual restriction fragment length polymorphism analysis showed that the phytoplasmas associated with the infected crossandra samples belonged to the 16SrII-D subgroup. This report describes the first identification of this phytoplasma strain in symptomatic crossandra plants in India.