Determination of Phytophthora species causing root and crown rot on tomato growing areas in Antalya province and reactions of some tomato genotypes against important species

Aims of this study were determination of the prevalence and incidence of root and crown rot disease and causing Phytophthora species in Antalya province, providing more than half of the tomato production of our country. During surveys, 170 greenhouses were investigated and, samples were taken from the areas where root and crown rot, stem blight and drying symptoms were observed. In the study, mean disease prevalence and incidence in Antalya province were found as 25.88% and 4.87%, respectively. There was no plant showing Phytophthora symptoms in Demre and Kepez districts, while the highest disease prevalence with 75% was found in Elmalı district. Totally 84 Phytophthora isolates were obtained by the isolations made from the symptomatic plant and soil samples. According to their morphological features and sequences of ITS gene regions, 80 isolates were identified as P. nicotianae, and remaining 4 isolate as P. capsici. In the pathogenicity test, made by cut stem end inoculation technique, all isolates were pathogenic on tomato plants. Susceptibilities of some tomato genotypes against P. nicotianae, which was found as the most prevalent species, were also investigated. In the experiment, 22 tomato genotypes (DT-7, DT-9, DT-15, DT-31, DT-50, DT-62, DT-90, DT-233, DT-253, DT-257, DT-284, DT-289, DT-296, DT-630, BH-4, TY-83, TY-84, YS-580, YS-583, FHG-470, A-286, Batem Özçelik) in the gene pool of BATEM used in tomato breeding studies, were used. As a result of the statistical evaluations, significant differences were found among the susceptibilities of the genotypes against the pathogen. DT-9 and DT-15 were found as the most susceptible genotypes, while A-286 was the most resistant one. It is tought that this study will be a base for breeding research and contribute integrated disease management.