Genotypic and phenotypic characterization of Phytophthora infestans populations from potato in Turkey

Late blight disease caused by Phytophthora infestans is an important yield reducing, prolific, and destructive pathogen of Solanaceae family members, mainly tomato and potato. P. infestans may cause entire crop loss unless controlled by chemical and cultural control measures. The Cukurova region of Turkey is one of the main potato-producing areas of Turkey and climatic conditions incite P. infestans to develop and cause severe yield losses in the region. A total of 186 isolates of P. infestans were obtained through survey studies conducted during the 2013-2014 potato-growing seasons in the Cukurova region comprised of Hatay, Adana and Mersin provinces in Turkey. All the isolates were analyzed for their metalaxyl resistance, mating type, mitochondrial DNA (mtDNA) haplotype and allozyme genotype diversity. P. infestans isolates were metalaxyl sensitive and both mating types were found in the potato-growing areas of the Cukurova region. The A1 mating type was more common (68.8%) than A2 (22.5%) and 8.6% of the P. infestans isolates were self-compatible. mtDNA haplotypes were diverse in the region and Ia was the most common type. Allozyme analyses revealed that the US-1 (Gpi 86/100) and US-6 (Gpi 100/100) patterns were prevalent in the potato-growing areas of the Cukurova region. This study contains the first data on molecular and biochemical characterization of potato late blight in Turkey.