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In this study, the phylogenetic relationship among Fusarium graminearum Schwabe isolates was established for the first time based on mitochondrial cox3 and rnl gene variations. The genes were amplified from 45 isolates purified from Türkiye and Iran together with 2 Korean strains by polymerase chain reaction. The amplicons were sequenced and nucleotide polymorphisms were detected by alignment. The phylogenetic relationship was constructed by using PAUP 4.0a with the maximum parsimony method. Fragments with 477 bp length, belonging to cox3, were obtained from 46 samples; 1547 bp-amplicons of rnl were produced from 45 samples. Sequence similarities were calculated as 30-100 % and 17-94 % for cox3 and rnl, respectively. Nucleotide variations within the rnl was found higher than within cox3. It was shown that SNPs and in-dels, found in coding regions, cause a codon change and may alter more than one codon by causing frame shift without affect gene functions. Bootstrap values belonging to cox3 and rnl dataset was found ranging from 57 to 84 %, and 54 to 100 %, respectively. Parsimony analysis revealed that Korean isolates were in monophyletic relationship with Turkish and Iranian isolates. It is proposed that the methodology can be applied to other fungal species because the phylogenetic relationships at the intraspecific level are able to establish among Fusarium species based on mitochondrial gene variation.

Abstract Fusarium culmorum produces polyketide-structured aurofusarin and its precursor metabolites. Aurofusarin biosynthetic pathway is catalysed by the products of eleven genes located in gene cluster. In this study, the effects of the expression levels of Pks12, Gip6, and Gip7, responsible genes for the intracellular steps of the pathway, on pigmentation were investigated in an F. culmorum field isolate. Presence of three genes were determined via PCR and sequencing. Their expressions were investigated by qPCR at 48th, 72nd, 120th and 168th hours. Aurofusarin and rubrofusarin production were verified by HPLC at the same time periods. Mycelial pigmentation, which was initially white, turned yellow, then carmine red during the seven-day culture. Pks12, Gip6, Gip7 genes with 1282, 449 and 1278 bps had sequence similarities (86,6%, 99,4% and 80,5% respectively) with the genes of reference (FcUK99). The ΣCp values of all genes ranged from 29th to 32nd cycles, whereas the Σ∆∆Ct values were calculated between 9,59 E-02 and 1,30 E-02. Relative quantification revealed these genes were controlled by down-regulation compared to the β-tubulin expression. Aurofusarin quantities ranged from 2,355 ppm to 27,350 ppm between the 72nd and 168th hours whereas the yield of rubrofusarin decreased from 0,098 ppm to 0,063 ppm. (4) Conclusion: This study becomes first report for both investigating the expression levels of the genes responsible for the catalysis of intracellular steps of aurofusarin biosynthesis in F. culmorum, and for examining the relationship between gene expression and mycelium pigmentation.

Fusarium graminearum and F. culmorum are phytopathogens, which cause destructive diseases in cereals. Epidemics of these phytopathogens are caused by mycotoxin contamination and the reduction of crop quality. In this study, the alteration due to in vitro camphor treatment on F. culmorum 9F and F. graminearum H11 isolates was investigated in terms of epigenetic, cellular, and transcription levels. Camphor with different concentrations (0.2, 0.4, 0.8, 1, 2, and 4 µg/µL) was applied to potato dextrose agar (PDA) growth media. The minimum inhibitory concentration (MIC) and the half maximal inhibitory concentration (IC50) were calculated as 2 and 1 µg/µL, respectively. hog1, mst20, CAT, POD, mgv1, stuA, and tri5 genes, which are related to various cellular processes and pathogenesis, were examined by qPCR assay. qPCR analysis showed that camphor treatment leads to the downregulation of tri5 expression but the upregulation of the remaining genes. Apoptosis and oxidative stress were confirmed via acridine orange/ethidium bromide (AO/EB) and dichlorofluorescin diacetate (DCF-DA) staining, respectively. Moreover, coupled restriction enzyme digestion-random amplification (CRED-RA) assay, used for DNA methylation analysis, was carried out to evaluate epigenetic alterations. The decrease in genomic template stability (GTS) values, which resulted due to the alterations in random amplified polymorphic DNA (RAPD) profiles caused by camphor treatment, were detected as 97.60% in F. culmorum 9F and 66.27% in F. graminearum H-11. The outer and inner methylated cytosine profiles are determined by CRED-RA assay as type I⁻IV epigenetic alterations. The outcomes indicated that camphor could lead to alterations at several molecular levels of F. graminearum and F. culmorum.