Determination of the expression of myb transcription factors targeted by mirnas during virus infection and drought stress in tomato (solanum lycopersicum l.)

Tomato (Solanum lycopersicum L.) is one of the important agricultural products of economic value in our country and in the world. However, there are many abiotic and biotic stress factors that negatively affect yield and quality in tomato production. Drought stress is a serious problem that limits growth and development in tomatoes. In addition, Tomato spotted wilt virus (TSWV) is a virus frequently encountered in tomato production areas and causes destructive effects. In recent years, several molecular networks have been identified, including perception of stress, signal transduction, regulatory elements and molecular mechanisms involved in the response pathways to abiotic and biotic stresses in plants. These mechanisms, which have been revealed on single stress factors in various plant species, are insufficient to explain the response mechanisms of plants facing multiple stresses in nature. Transcription factors (TFs) and microRNAs (miRNAs) play a key role in regulating the response mechanisms of plants to environmental stresses. These constructs are responsible for the expression and / or repression of genes involved in many processes such as growth and development, adaptation to environmental stresses and tolerance. This thesis study, TSWV infection, drought stress and and TSWV/drought application of TSMV-sensitive Alsancak and TSWV-resistant Sedir tomato cultivars of SlMYB44, SlMYB73, SlMYB96, SlMYB101 and Sly-miR159 genes expression levels were determined. For this purpose, leaf samples were taken from tomato plants on the 7., 14. and 21. days of TSWV infection and on the 0., 3., 5. and 7. days of drought stress and TSWV/drought application. Changes in gene expression levels were determined by real-time RT-PCR using 2-∆∆CT method. As a result of the analyzes, it was determined that SlMYB44, SlMYB73, SlMYB96, SlMYB101 and Sly-miR159 genes were expressed at different levels according to the stress type during both single and multiple stress applications in tomato.