Title
Polymorphisms in P. infestans: four mitochondrial haplotypes are deteced after PCR amplification of DNA from pure cultures or from host lesions.
Abstract
Four pairs of primers were designed for PCR amplification of known polymorphic regions of the mitochondrial
genome of Phytophthora infestans. Digestion of the amplified products with restriction enzymes allows
identification of previously identified haplotypes. Product P2 cut with MspI uniquely identifies haplotypes Ib
and IIa, while types Ia and IIb are differentiated by digestion of product P4 with EcoRI. Digestion of products
P1 and P3 gave results similar to that with digestion of P4, but amplification of these products was less robust.
Thus, all four common haplotypes are identified by amplifying and digesting products P2 and P4. Identification
of haplotypes was also possible from DNA extracted directly from small, late-blight lesions on both tomato and
potato leaves, making isolation of the fungus unnecessary. A rapid and efficient method of monitoring changes
in the pathogen population is facilitated. These PCR primers were also useful for differentiating other
Phytophthora species.
Authors
GARETH W. GRIFFITH* AND DAVID S. SHAW
Journal
Appl. Environ. Microbiol., 1998 : 64(0), 4007~4014