Occurrence of pith necrosis caused by Pseudomonas fluorescens on tomato plants in Turkey

is one ofthe most destructive diseases of tomato in Europe. Pithnecrosis of soil-grown glasshouse tomatoes was observedin Adana, Mersin, Antalya, Mugla and Izmir, in theMediterranean and Aegean regions of Turkey, during latewinter and spring of 2002 and 2003. Symptoms wereyellowing and wilting of lower leaves which progressedupwards, brown areas on stems and yellow-brown dis-coloration of the pith. Bacteria were consistently isolatedfrom affected plants and these formed fluorescent colonieson King’s medium B. Twenty-seven bacterial isolates werepurified and used for further studies. In tests performedaccording to Lelliott & Stead (1987), all isolates wereGram-negative, oxidase-, arginine dihydrolase- and gela-tin liquefaction-positive. None caused soft rot on potatoslices within 48 h at 25 ° C or produced levan-type colonieson sucrose nutrient agar, and all were negative in tobaccohypersensitivity and nitrate reduction tests. Fatty acid(FA) analysis identified the isolates as