Duplex PCR assay for detection of chickpea chlorotic dwarf virus and peanut witches' broom phytoplasma in chickpea.

A duplex PCR assay was standardized by optimizing PCR reaction constituents and cycles for the simultaneous detection of chickpea chlorotic dwarf virus (CpCDV) and a peanut witches' broom (PnWB) phytoplasma associated with the chickpea stunt disease. Coat protein gene and gene specific primers for CpCDV and phytoplasmas were used. Different concentrations of the PCR components such as polymerase, primers and PCR annealing temperature were standardized for the identification of the two agents by a duplex PCR assay. Expected amplicons of 590 bp for CpCDV and 1090 bp for phytoplasmas were consistently amplified from the symptomatic chickpea tissues. That resulted in equally efficient and sensitive in detecting single or mixed infection of CpCDV and PnWB phytoplasma in 148 symptomatic chickpea stunt samples collected in two states of India. The results indicate the robustness in the detection of pathogens present in chickpea showing stunt disease and for theoretical use in epidemiological studies that would help the appropriate disease management strategies.