Effeciacy of cluster thinning on semiquinone radicals, phytohormones, sugar uptake and plant nutrients in different organs of pistachio

Pistachios are known as "Green Gold" in the Middle East region, and provide important revenue for producers. Pistachio cultivation is done economically and has a big potential in Turkey. "Kirmizi" is one of the commercially grown varieties produced numerously in Turkey. Since pistachio is a type of nut that shows alternate bearing phenomena, and so production varies according to years and countries. The main goal of this thesis was to examine the effect of the flower cluster thinning application, on metabolic responses of pistachio (Pistacia vera L.cv. Kirmizi) depending on the time that has elapsed since making the flower cluster thinning. The first objective was to determine whether the above treatment alters the generation of semiquinone radicals in pistachio organs (fruits, leaves and shoots). The second objective was to verify whether it causes elevated generation signaling molecules, i.e. phytohormones such as abscisic acid (ABA), salicylic acid (SA) and indole-3-acetic acid (IAA) and changes in the sequence/period of their generation, and in the transduction of signals from organ to organ. Moreover, the third objective was to determine whether changes in the sugar levels occur after the flower cluster thinning. Additionally, it was aimed to determine the nutrient element concentrations in leaves, shoots and fruits after the flower cluster thinning application in the "Kırmızı" pistachio variety