SIGMA JOURNAL OF ENGINEERING AND NATURAL SCIENCES, cilt.42, sa.2, ss.450-458, 2024 (ESCI)
Fusarium graminearum is the primary cause of Fusarium head blight (FHB) epidemics worldwide. The characterization of F. graminearum isolates via physiological, genetic, and transcriptional analysis was aimed in the study. A total of 31 isolates and a reference strain were grown on potato dextrose agar (PDA) for 7 days. According to measurements on the 4th and 7th day of cultivation, their minimum and maximum mean linear growth rates (LGRs) were calculated as 9.62±0.44 to 13.32±0.69 mm/day, respectively. Isolates were grouped as x<10 mm/day and 10<x<20 mm/day. Amplification products of the internal transcribed spacer (ITS) regions of ribosomal RNA (rRNA) coding sequences with 1147 bp were digested with three restriction endonucleases in all isolates. Two different restriction profiles were obtained with PstI and Eco31I digestions whereas EcoRI yielded single banding profile. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) genotyping was able to distinguish isolates within the same species under four groups. FgMgv1, tri4 and MAT1-1-2 gene expression
levels of selected one each isolate (FgM1, Fg174 and Fgsh4) with the highest, moderate and the lowest LGRs (13.32±0.69, 11.32±0.15 and 9.62±0.44 mm/day, respectively) were examined by qRT-PCR. Relative mRNA abundance values of FgMgv1 were 1.715±0.199, 0.089±3.166e004 and 0.020±1.408e-004 for FgM1, Fg174 and Fgsh4, respectively. Similarly, these values for tri4 were calculated as 0.081±0.009, 0.016±0.004 and 0.002±4.338e-005 and for MAT1-2 as 2.097±0.484, 1.901±0.195, 1.047±0.136. Expression levels of these genes were significantly higher in FgM1 with the highest LGR values. Outcomes showed that PCR-RFLP method may become possible to distinguish the members of Fusarium species complex more clearly. Moreover, determined correlation among the LGRs of isolates, their aggressiveness and mycotoxin production capacities provided basic knowledge for supporting studies intended to control FHB infections.