Bu çalışmada, domateste bakteriyel benek hastalığı etmeni Pseudomonas syringae pv. tomato (PST)'ya karşı dayanıklılık reaksiyonlarının belirlenmesi amacıyla 50 farklı domates çeşidi incelenmiştir. İki farklı Pst izolatı( YA-1 ve YA-2)'nın 108 hücre/ml yoğunluktaki süspansiyonu ile inokule edilen ve steril saf su ile muamele edilen kontrol bitkiler, 250C ve %60-70 nispi nemde tutulmuşlardır. Oluşan tipik yaprak lekeleri inokkulasyondan sonraki 21. günde sayılmışlar, bitkilerin dayanıklılık düzeyleri Chambers ve Merriman skalasına göre sınıflandırılmıştır. Sağlıklı domates bitkilerinde, patojene karşı dayanıklılık geninin (pto) 963 bp'lik fragmentinin varlığı SSP17 ve JCP32 spesifik primerleri kullanılarak PCR yöntemiyle tespit edilmiştir. Veriler varyans analizi (Anova ver. 10) ve MSTAT programında Duncan çoklu karşılaştırma testiyle değerlendirilmiş ve istatistiki olarak önemli bulunmuşlardır (p?0,01). İncelenen 50 farklı domates çeşidinden 15'inde pto geninin varlığı belirlenirken, çeşitlerin farklı bakteriyel izolatlara karşı verdikleri reaksiyonlar farklılıklar göstermiştir.
Pseudomonas syringae pv. tomato is the causative agent of the bacterial speck disease of tomato (Lycopersicon lycopersicum), a disease that occurs worldwide and causes severe reduction in fruit yield and quality. Disease resistance conferred by the pto gene, encodes a serine?threonine protein kinase, is one of the first R-genes to be cloned and sequenced. In this research, the resistance reactions of 50 popular tomato cultivars which are grown commonly in Turkey against P. s. pv. tomato causal agent of bacterial speck disease were determined. Six-week-old plants were inoculated by spraying of P. s. pv. tomato YA-1 and YA-2 strains (108 cfu ml-1) with an airbrush until leaf surfaces were uniformly wet. After inoculation, the plants were incubated at 25±1 °C in 60-70?% relative humidity with a 12 h photoperiod and the disease progress occurred on the seedling leaves by P. s. pv. tomato was followed by counting the dark brown-black leaf necroses in 21st days after inoculation of the seedlings. Each experiment was performed at least three times and control plants were sprayed with sterile distilled water. The results of resistance reactions on plants were evaluated according to Chambers and Merriman scale. The resistance levels of the cultivars were statistically determined by using ANOVA variance analyze and Duncan multiple, range tests. Presence of pto gene (963 bp) in the tomato cultivars was verified by using the primers SSP17 and JCP32 by PCR and the gene was determined in 15 different tomato cultivars.
