PCR method to identify Tilletia indica
A PCR method has been developed in USA to identify Tilletia indica (EPPO A1 quarantine pest), the causal agent of Karnal bunt of wheat. The authors pointed out that a major problem encountered with the identification of T. indica in wheat shipment is the possible confusion with other Tilletia species, and in particular with T. barclayana (kernel smut of rice) which produces very similar teliospores. A set a T. indica-specific primers were used in this study, and their specificity was evaluated by testing 78 isolates of T. indica and 79 isolates of other Tilletia species (T. barclayana, T. controversa, T. tritici, T. laevis, T. fusca). By using teliospores germinated from a seed wash extraction method of infested grain, the authors demonstrated that T. indica can be reliably detected at an infestation level of 5 teliospores per 50 g of grain sample. The authors concluded that their method could be very useful in international trade to detect infected seed lots.
Sources
Smith, O.P.; Peterson, G.L.; Beck, R.J.; Schaad, N.W.; Bonde, M.R. (1996) Development of a PCR-based method for identification of Tilletia indica, causal agent of Karnal bunt of wheat.
Phytopathology, 86(1), 115-122.