2011 YÜksek lisans tez özetleri

Genotyping Of Fusarium Graminearum And Fusarium Culmorum Isolates By Microsatellite Markers

It is aimed to identify fifty two isolates (thirty one of F. graminearum and twenty one of F. culmorum) causing disease on wheat, barley and maize, obtained from culture collections of Samsun Ondokuz Mayıs University and Iran Isfahan Technology University, and to determine the diversity among F. graminearum and F. culmorum isolates caused by alteration of repeat unit and number represented on three microsatellite regions (Ms-Fg97, Ms-Fg98, Ms-Fg103), which not distributed throughout the genomes of these two species. For this purpose, the Fusarium isolates in pure cultures were identified at phylum, group and species levels, by amplifying 28S rRNA gene, tri5 gene and two different SCAR markers (UBC85 and OPT18), respectively. Thirty one isolates were determined as F. graminearum, and twenty one as F. culmorum. Ms-Fg97, Ms-Fg98 and Ms-Fg103 microsatellite markers carry (CCTA)₈, (GCAA)₆, (TG)₁₉ repeat motifs, respectively, according to literature. All isolates were determined as homozygote with respect to three microsatellite loci, in this study. Ms-Fg97 marker was not amplified in F. graminearum sh1 and F. culmorum F13 isolates. Polymorphic microsatellite markers were only obtained from F. graminearum isolates. Randomly chosen twelve monomorphic and polymorphic DNA fragments were sequenced. Ms-Fg97 and Ms-Fg98 microsatellite regions, amplified in F5 and sh14 isolates, showed 100% similarity with contigs (supercontig 3 in chromosome 3, supercontig 2 in chromosome 5) of the reference genome (Gibberella zeae PH-1). Remaining isolates also displayed high level of homology (86-98%) with the reference genome, but variation was detected between the isolates, carrying expected allele size, and G.zeae PH-1 genome with respect to repeat motif and repeat number. (CCTA)₈ unit in Ms-Fg97 microsatellite region of F5 isolate was found totally identical with the reference genome. It was carried out that Ms-Fg98 marker is represented by (GCAA)₄ motif instead of (GCAA)₆ on sh14 isolate, Ms-Fg103 is represented by (TC)₁₉ motif instead of (TG)₁₉ and the microsatellit regions, carry the two repeat motifs, display high similarity with the same regions which belong to the reference genome. Despite repeat motif similarities in five isolates (F7, sh14, 4F, 56, T9), repeat number differences were detected among them. Moreover, it was shown that microsatellite motif which belongs to other five isolates (F9, T7, 2F, 3F, F3) was carried differently from G. zeae PH-1 genome. This master thesis has shown the genetic variability among the microsatellite loci, repeat motif and repeat number carried in Fusarium isolates causing disease on cereals in Turkey and Iran.

  

ÇELİK Bilge

Danışman : Doç.Dr. Ercan ARICAN

Anabilim Dalı : Moleküler Biyoloji ve Genetik

Mezuniyet Yılı : 2011

Tez Savunma Jürisi : Doç. Dr. Ercan ARICAN

Prof. Dr. Nermin Gözükırmızı

Prof. Dr. Keriman Günaydın

Doç. Dr. Gülruh Albayrak

Doç. Dr. Tamer Özcan