HRM: A TOOL TO ASSESS GENETIC DIVERSITY OF PHYTOPHTHORA CAMBIVORA ISOLATES
A. Zambounis, A. Xanthopoulou, P. Madesis, A. Tsaftaris, A. Vannini, N. Bruni, A. Tomassini, G. Chilosi, A.M. Vettraino
Phytophthora cambivora (Petri) Buisman is a widespread soil born oomycete causing root rot on several woody species. Together with P. cinnamomi, it is considered the most pathogenic species associated with chestnut ink disease all over Europe. Currently, no efficient control strategies are available for ink disease. Information about the population genetic variability of P. cambivora is quite limited, despite that it might be useful for the development of integrated control programmes. To our knowledge no such studies have been conducted in chestnut-growing regions in Europe. Therefore, we set up a reliable and accurate genotyping approach named HRM (High Resolution Melting) analysis in order to assign efficiently and accurately the signatures of genetic variation among P. cambivora isolates collected in a chestnut growing area in Central Italy. Degenerated primers were designed in conserved regions of exons 3 and 4 of the gene locus Ypt1. The resulting melting curves profiles specifically assigned all P. cambivora isolates in eight unique HRM genotypes according to their normalized curve profiles implying high intraspecific genetic variation of these isolates. Data confirmed that the HRM approach might be on a wide scale a rapid and reproducible technique for efficient intraspecific genotyping of P. cambivora populations.