Comparison of the activities of some mobile genetic elements (Transposon) associated with drought in some citrus rootstocks

Citrus is a commercially important genus of the Rutaceae family and is a widely grown fruit group in the world. Considering the agricultural land used in the world, drought stress has the highest rate of 26% among the stress factors. In this case, it is very important to develop drought-resistant genotypes. Transposon studies have gained importance in citrus plants rich in transposons. Transposons are common components of plant genomes, functioning at transcription and integration levels, and their quantification and transposing abilities make them potential markers. Transposons also serve as a rich source of polymorphism. In this study, Cs18SrR, Cs_Pol-1, CsCLCoy_1, CsCc1-8, Retro_Cc1_32, Sire_Cc1, Sire_Cc1_74 and Sire_Cc1_83 transposons were studied for the first time under drought stress, Tuzcu 31-31, Cleopatra mandarin, Macrophylla and Rough Limon used as citrus rootstocks plants were studied. Samples were taken from the root and leaf tissues of the examined genotypes. Expression levels of some transposon genes, which have important effects on gene function and genome, were measured by real-time PCR in different 4 rootstock genotypes that were subjected to drought stress. As a result, with this thesis study, new information has been brought to the literature about the changes at the molecular level developed by some citrus fruits under drought stress. With the results obtained, the gene expression levels of the retrotransposons used between genotypes are discussed.