Genomic fingerprinting and PCR analysis: rapid, sensitive and inexpensive means of differentiating strains of Pseudomonas-solanacearum

Analysis of the total genomic restriction pattern, and restriction analysis of an amplified fragment of the endopolygalacturonase gene (pehH) both readily differentiate isolates, subdividing P. solanacearum into groups based on genetic relationships. They have allowed rapid identification of unknown isolates, and provided information on the evolution and epidemiology of individual strains. DNA fingerprinting has been used to establish the current distribution of individual strains, to reconstruct their possible origins and subsequent dissemination. In some cases, individual strains were shown to have restricted natural geographic distribution and-or plant hosts. The established classification schemes of biovars and races were confirmed by this analysis, with the exception of race 1, which cut across biovars and genetic groups.