Polymorphisms in Phytophthora infestans: four mitochondrial haplotypes are detected after PCR amplification of DNA from pure cultures or from host lesions

A study was conducted to analyze a polymerase chain reaction-based technique for the rapid detection of mtDNA polymorphisms in Phytophthora infestans. Fungi from agar cultures or infected host tissues were utilized to carry out the analysis. Leaf and stem lesions of late blight were obtained from naturally infected crops while DNA was determined by cutting slabs of agar-containing mycelium. In addition, polymerase chain reaction was carried out with the PC2 PCR thermal cycler.