Identification of a ‘Candidatus Phytoplasma trifolii’ strain infecting brinjal in Maharashtra, India: a new regional record

Brinjal little leaf disease, associated with the presence of phytoplasmas, is one of the most destructive diseases of brinjal in India, leading to considerable yield losses. The disease is predominantly associated with 16SrVI-D phytoplasmas throughout the Indian subcontinent, and reports of other phytoplasma subgroups remain sporadic and geographically limited. During comprehensive field surveys conducted in November 2025 in the Salegaon region near Pune, Maharashtra, characteristic little leaf symptoms were observed in brinjal cultivations with incidence ranging from 12% to 15%. Molecular detection using nested PCR targeting the 16S rRNA gene, followed by phylogenetic analysis, confirmed the presence of ‘Candidatus Phytoplasma trifolii’ belonging to the 16SrVI-A subgroup. Sequence analysis revealed 99.94% nucleotide identity with the reference strain (GenBank accession number AY390261). This represents the first report of ‘Ca. P. trifolii’ (16SrVI-A subgroup) in Maharashtra and constitutes the first westernmost geographic record of this subgroup presence in brinjal in India, extending its known distribution beyond Uttar Pradesh. The geographic expansion of this strain has important implications for disease management strategies, insect vector ecology, and regional surveillance programs. This finding highlights the genetic diversity within phytoplasma populations infecting brinjal in India and underscore the necessity for continuous molecular monitoring to track pathogen distribution and molecular diversity. The detection of 16SrVI-A subgroup in Maharashtra suggests potential pathogen dissemination through infected planting material or insect vector movement, necessitating enhanced quarantine measures and integrated disease management approaches for a sustainable brinjal production.