Pathogenicity, molecular diagnosis and obtained nit mutants of agent fusarium oxysporum f. sp. lycopersici and f. oxysporum f. sp. radicis-lycopersici in tomato in the central black sea region

In this study, it was aimed to determine prevalence and severity of Fusarium wilt agent, Fusarium oxysporum f. sp. lycopersici (FOL) and Fusarium root and crown rot agent Fusarium oxysporum f. sp radicis-lycopersici (FORL) cannot be distinguished from each other morphologically in tomato production areas of Central Black Sea Region, distinguish between FOL (race 1, 2, 3) and FORL isolates using molecular methods, their pathogenicity and identification of nit mutants. As a result of the survey conducted to determine the prevalence and severity of wilt and root and crown rot diseases, wilt symptoms were most common in Ordu (11%), and the highest disease severity was observed in Ordu (3.3%). Root and crown rot disease symptoms were most common in Amasya with 52.3%, while the highest disease severity was found in Amasya (19.4%). While 121 FORL isolates were obtained from diseased plant samples taken from the surveyed areas, 50 (41.3%) of the isolates were from Samsun, followed by 40 (33.1%) Tokat, 20 (16.5%) Amasya, six (5%) Çorum and five. (4.1%) was obtained from the province of Ordu. A total of 27 isolates were obtained from the agent FOL with three different races, seven from Tokat and four FOL-1 isolates from Samsun, three FOL-2 isolates from Tokat and five from Tokat, four from Samsun, three from Amasya and one from Ordu isolates of the FOL-3 strain were obtained. FOL isolate was not obtained from Çorum province. Thus, it has been revealed that FORL is the most common subtype in our region and has the highest disease severity. It was determined that all three races (1, 2, 3) belonging to the FOL agents were in the Central Black Sea region. Evaluated criteria of the isolates obtained as a result of the pathogenicity test showed significant differences with the control (P<0.01). It was understood that there were statistical differences between the isolates in relation to plant growth parameters. In addition, a negative relationship was determined between the scale values of the isolates and plant growth parameters. When the nit mutants obtained were evaluated according to their phenotypes, nit1 was found at the rate of 74% (28) for FOL, followed by NitM at 24% (9) and nit3 at 2% (1). For FORL, nit1 was obtained with 82% (123), followed by NitM with 15% (22) and nit3 with 3% (5). Keywords: Root and crown rot, Wilt, Plant growth, Pathogenicity, Nit mutant