First report on the molecular identification of phytoplasma (16SrII-D) associated with witches' broom of Kalmegh (Andrographis paniculata) in India.

Andrographis paniculata (family Acanthaceae), also known as “King of Bitters” or Kalmegh, is an important medicinal plant used for the treatment of various diseases. It has antimicrobial, antiviral, anti-inflammatory, hepatoprotective, antidiabetic, antihyperglycemic, and antioxidant properties (1). During June 2014, while performing a routine survey of the commercial trial fields of Kalmegh at Central Institute of Medicinal and Aromatic Plants (CIMAP), Lucknow, India, typical phytoplasma disease symptoms such as virescence, proliferation, and witches' broom along with little leaf and stunted growth were observed. The disease incidence was estimated to be approximately 7 to 10%. To ascertain the presence of phytoplasma, 16 samples of leaves were collected from nine different field sites, and total genomic DNA was extracted from the symptomatic and symptomless Kalmegh plants by the CTAB method. Direct and nested PCR assays were performed targeting the 16S rDNA using generic phytoplasma primer pairs P1/P6 f...