Tez özetleri Astronomi ve Uzay Bilimleri Anabilim Dalı 2

Genotypıng of Fusarium graminearum Isolates wıth Caps Markers
Fusarium graminarum is a prevalent plant pathogen which has a high intraspecific diversity all over the world. Therefore, genotyping of isolates belonging to the species has a great importance. In this thesis, it was aimed to both genotype of 45 F. graminearum isolates obtained from different geographic regions and determine of single nucleotide polymorphisms (SNPs). In this context, CAPS molecular marker method was used in the analysis of four genes (histone 3, ribosomal protein, actin and hypothetical protein genes) and one RAPD marker (D3G3 related to hypothetical protein). SNPs were searched by digestion of polymerase chain reaction (PCR) amplification products of them with seven different restriction endonucleases (Ava II, Rsa I, Fok I, Hae III, EcoR I, Cla I, Tfi I).
In this study, polymorphism was not obtained in histone 3 and actin genes. However, transversion of C to G and transition C to T as SNPs were determined with Tfi I restriction digestion of ribosomal protein gene in F5 and F7 isolates, respectively. In addition, single (G) and double base deletion (AG) were found in the gene sequences. Besides, one SNP (C to T transition) and an deletion with 6 nucleotides (GCGGGG) were seen in D3G3 RAPD marker of Sh15 isolate. EcoR I restriction digestion revealed these differences. Also, a transition type mutation (G to A) was determined with the Ava II restriction digestion of gene sequences encoding hypotheticial protein in Sh14 isolate. It was observed that none of these mutations resulted in stop codon in open reading frame (ORF) of studied gene regions and in marker sequences. As a result, mutations- deletions together with SNPs- were found in the genes which are participating in basic cellular process by employing both RAPD with CAPS marker analysis, in this study. It is estimated that these mutations could change amino acid sequence of related proteins.