Occurence and control measures of Fusarium wilt (Fusarium oxysporum f. sp. dianthi) in carnation growing areas in Izmir province

Fusarium oxysporum f. sp. dianthi (Fod) that causes Fusarium wilt is the most common and destructive biotic agent encountered in carnation production in the world and in our country. In this thesis, it was determined that the prevalence of the disease was found to be around 55% as a result of the survey and isolation studies carried out in greenhouse cut flower carnation areas in Izmir between April-August 2016. Total of 100 Fusarium spp. isolates were obtained from carnation greenhouses. 84 isolates were identified as Fusarium oxysporum f. sp. dianthi (Fod) and the remaining 16 as Fusarium proliferatum after morphological and molecular diagnoses. As a result of the PCR tests performed with race-specific primer pairs, it was determined that 67 of 84 Fod isolates were Fod race 2 and 16 were Fod race 1/8. In managemet studies of carnation wilt, the best result was obtained from prochloraz and subsequently bromuconazole in vitro and bromuconazole gave the most effective result with a 71,22% effect in vivo. Among soil disinfection applications, soil solarization with 76,3% in the first growing season, dazomet with 77,2% in the second season, and dimethyl disulfide (DMDS) with 86,30% in the third season had the best effect. The expected results in the fungicide trials could not be achieved because of high contamination of seedlings and large variation between plots in the first growing season, and very low disease incidence in the second growing season.