title: Characterization of Phytophthora infestans resistance to mefenoxam using FTIR spectroscopy.
abstract: Phytophthora infestans (P. infestans) is the causal agent of late blight in potato and tomato. This pathogen devastated the potato crops in Ireland more than a century years ago and is still causing great losses worldwide. Although fungicides controlling P. infestans have been used successfully for almost 100 years, some isolates have developed resistance to most common fungicides. Identification and characterization of these resistant isolates is required for better control of the disease. Current methods that are based on microbiological and molecular techniques are both expensive and time consuming. Fourier Transform Infra-Red spectroscopy (FTIR) is an inexpensive and reagent-free technique that provides accurate results in only a few minutes. In this study the infrared absorption spectra of the sporangia of P. infestans were measured to evaluate the potential of FTIR spectroscopy in tandem with multivariate analysis in order to classify those sporangia into those that were resistant and those that were non-resistant to the phenylamide fungicide mefenoxam. Based on individual measurements, our results show that FTIR spectroscopy enables classification of P. infestans isolates into mefenoxam resistant and mefenoxam non-resistant types with specificity of 81.9% and sensitivity of 75.5%. Using average spectra per leaf, it was possible to improve the classification results to 88% sensitivity and 95% specificity.
authors.affiliation: Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
authors.forename: A
authors.initials: A
authors.lastname: Pomerantz
authors.affiliation: Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel.
authors.forename: Y
authors.initials: Y
authors.lastname: Cohen
authors.affiliation: Department of Physics, SCE - Shamoon College of Engineering, Beer-Sheva 84100, Israel.
authors.forename: E
authors.initials: E
authors.lastname: Shufan
authors.affiliation: Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel.
authors.forename: Y
authors.initials: Y
authors.lastname: Ben-Naim
authors.affiliation: Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
authors.forename: S
authors.initials: S
authors.lastname: Mordechai
authors.affiliation: Department of Physics, SCE - Shamoon College of Engineering, Beer-Sheva 84100, Israel. Electronic address: ahmad@sce.ac.il.
authors.forename: A
authors.initials: A
authors.lastname: Salman
authors.affiliation: Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel. Electronic address: mahmoudh@bgu.ac.il.
authors.forename: M
authors.initials: M
authors.lastname: Huleihel
mesh_terms: D000409:Alanine / Q000031:analogs & derivatives* / Q000494:pharmacology; D016002:Discriminant Analysis; D004351:Drug Resistance; D005659:Fungicides, Industrial / Q000494:pharmacology; D018551:Solanum lycopersicum / Q000254:growth & development; D055750:Phytophthora infestans / Q000737:chemistry / Q000187:drug effects* / Q000302:isolation & purification; D010935:Plant Diseases / Q000469:parasitology; D018515:Plant Leaves / Q000469:parasitology; D025341:Principal Component Analysis; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D005659:Fungicides, Industrial; C473256:mefenoxam; D000409:Alanine