GC-MS metabolite profiling of Phytophthora infestans resistant to metalaxyl
Phytophthora infestans is the most important potato pathogen worldwide. Various alternatives have been used to control the pathogen, including continuous applications of phenylamide fungicides which has caused a rapid development of resistance in populations of P. infestans. Despite the importance of the disease, metabolite profiling of fungicide-resistant P. infestans has not been reported. In vitro resistance of Phytophthora infestans isolates to metalaxyl was characterized and metabolic changes in resistant isolates were evaluated at low (0.5 mg/L) and high (100 mg/L) concentrations of the fungicide. About 70% of the isolates tested showed resistance to metalaxyl and a total of 49 metabolites were differently expressed in resistant isolates growing in the presence of the fungicide. Principal components analysis revealed a distinct metabolite profile of resistant isolates exposed to both low and high levels of metalaxyl. The main metabolites responsible for the clustering in both fungicide concentrations included fatty acids such as hexadecanoic and octadecanoic acids, sugars such as glucose and fructose, aminoacids such as proline and valine, and organic acids such as butanedioic and propanoic acids. Potential resistance-related metabolic pathways are mostly involved in the regulation of the pathogen’s membrane fluidity and included the fatty acid biosynthesis as well as the glycerophospholipid metabolism pathways. This is the first metabolomic-based characterization of fungicide resistance in plant pathogens.
KeywordsPotato Late blight Metabolomics Fungicide resistance GC-MS
This research was financially supported by Escuela Superior Politécnica del Litoral (CIBE-ESPOL) and VLIR NETWORK Ecuador. Authors thank Jose Ochoa from the National Institute of Agricultural Research for donating the P. infestans isolates for this research.
- Cevallos-Cevallos, J., García-Torres, R., Etxeberria, E., & Reyes-De-Corcuera, J. I. (2011a). GC-MS analysis of headspace and liquid extracts for metabolomic differentiation of citrus huanglongbing and zinc deficiency in leaves of “Valencia” sweet orange from commercial groves. Phytochemical analysis : PCA, 22(3), 236–246.CrossRefPubMedGoogle Scholar
- Cevallos-Cevallos, J., Danyluk, M. D., & Reyes-De-Corcuera, J. I. (2011b). GC-MS based metabolomics for rapid simultaneous detection of Escherichia coli O157:H7, Salmonella Typhimurium, Salmonella Muenchen, and Salmonella Hartford in ground beef and chicken. Journal of Food Science, 76(4), M238–M246.CrossRefPubMedGoogle Scholar
- Davidse, L. C., Gerritsma, O. C. M., Ideler, J., Pie, K., & Velthuis, G. C. M. (1988). Antifungal modes of action of metalaxyl, cyprofuram, benalaxyl and oxadixyl in phenylamide-sensitive and phenylamide-resistant strains of Phytophthora megasperma F. Sp. medicaginis and Phytophthora infestans. Crop Protection, 7(6), 347–355.CrossRefGoogle Scholar
- Goodwin, S., Sujkowski, L., & Fry, W. (1996). Widespread distribution and probable origin of resistance of metalaxyl in clonal genotypes of Phytophthora infestans in the United States and western Canada. Ecology and Epidemiology, 86(7), 793–800.Google Scholar
- Riveros, F., Sotomayor, R., Rivera, V., Secor, G., & Espinoza, B. (2003). Resistance of Phytophthora infestans (Montagne) de Bary to metalaxyl in potato crops in northern Chile 1. Agricultura tecnica de Chile, 63(2), 117–124.Google Scholar
- Robson, G. D., Wiebe, M., Kuhn, P. J., & Trinci, A. P. J. (1990). Inhibitors of phospholipid biosynthesis. In P. J. Kuhn, A. P. J. Trinci, M. J. Jung, M. W. Goosey, & L. G. Copping (Eds.), Biochemistry of Cell Walls and Membranes in Fungi - Google Libros (1st ed., pp. 261–279). New York.Google Scholar
- Tamura, K., Stecher, G., Peterson, D., Filipski, A., & Kumar, S. (2013). MEGA6: Molecular evolutionary genetics analysis version 6.0. Mol. Biol. Evol, 30, 2725–2729.Google Scholar
- Yogendra, K. N., Kushalappa, A. C., Sarmiento, F., Rodriguez, E., Mosquera, T., Bassard, J., et al. (2014). Metabolomics deciphers quantitative resistance mechanisms in diploid potato clones against late blight. Functional Plant Biology, 42(3), 284–298.Google Scholar
- Yogendra, K. N., Kushalappa, A. C., Sarmiento, F., Rodriguez, E., & Mosquera, T. (2015). Metabolomics deciphers quantitative resistance mechanisms in diploid potato clones against late blight. Functional Plant Biology, 42(3), 284–298.Google Scholar