First report on the association of ‘Candidatus Phytoplasma asteris’ with lethal wilt disease of coconut (Cocos nucifera L.) in India

Abstract

Lethal wilt disease of coconut, reported as a disease of unknown etiology as early as 2007, was for the first time found consistently in association with a phytoplasma in diseased coconut trees in Thanjavur, Thiruvarur and Pudukkottai districts in Tamil Nadu on the southeastern coast of India. Nested PCR with phytoplasma-specific universal primers and in silico restriction analysis of 16S rDNA sequences revealed the association of ‘Candidatus Phytoplasma asteris’ (16SrI-B) group phytoplasma, which was confirmed by sequence analysis of translation elongation factor (tuf) and ribosomal protein (rp) genes. Because this disease kills affected palms within 5 months, recommendations are given to arrest the spread of the pathogen to other coconut-growing regions in the country.