Identification of ‘Candidatus Phytoplasma asteris’ associated with witches’ broom disease of linseed and its weed host in India Gopala1,*, Nair Beena1, Kaushal Ashulata2, Rathnakumar Arulthambi Luke3, Sujatha Mulpuri3, Rao Ashutosh4, Mane Shyamsunder Shioram5, Parbat Jagdish Madhukar1 1Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola, AICRP on Linseed, College of Agriculture, Nagpur-440001, Maharashtra, India 2Indira Gandhi Krishi Vishwavidyalaya, Department of Plant Pathology, College of Agriculture, Raipur-492012, Chhattisgarh, India 3Indian Institute of Oil Seeds Research, Rajendra Nagar-500030, Hyderabad, India 4National Bureau of Plant Genetic Resources, Division of Plant Quarantine, Pusa Campus, New Delhi-110012, India 5Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola, Department of Plant Pathology, India *Corresponding author e-mail: Gopala (gplpatho33@gmail.com)
Online Published on 11 January, 2024. Abstract During March 2023, stem fasciation and witches’ broom symptoms were observed in linseed and Parthenium hysterophorus in Raipur, India. Total DNA from both symptomatic linseed and Parthenium plants was subjected to nested PCR assays using universal phytoplasma specific primers P1/P7 followed by R16F2n/R16R2 to amplify the 16S rDNA fragments. PCR amplification with primer pair P1/P7 did not yield expected 1.8 kb products of 16S rRNA gene region from any of the symptomatic tested samples. However, DNA fragments of approximately 1.2 kb were amplified from linseed and P. hysteroporus using R16F2n/R16R2 primer pair in nested PCR reaction. BLASTn comparison and phylogenetic analysis of 16S rDNA phytoplasma sequences of linseed and Parthenium witches’ broom phytoplasma strains revealed the presence of ‘Candidatus Phytoplasma asteris’ (16SrI group) in the symptomatic samples. The virtual RFLP analysis of the 16Sr DNA sequence of linseed and Parthenium further identified the phytoplasma strains as belonging to the 16SrI-B subgroup. The Parthenium weed was identified as a alternative host of the 16SrI-B group phytoplasma detected in the present study and may play an important role in its natural spread. Top Keywords Alternative host, Phytoplasma, Flax, Parthenium, 16S rDNA. Top |