REACTION OF SELECTED TYPES OF PLANT GROWTH REGULATOR FOR WATER STRESS ON WINTER WHEAT

The aim of this work was to clarify the impacts of water stress and describe the effects of stress on winter wheat. We observed the morphological and growth changes, as well as changes in selected physiological functions of plants. In this work we address the possible adaptive or defence mechanisms of plants to water scarcity. The main objective of my work was to monitor the impact of plant growth regulators on physiological parameters under drought stress. The experiment was conducted on a field experimental station in Zabcice on variety Matylda. This area (Zabcice) is located in a warm area with prevailing continental climate, with average annual rainfall of 482 mm and an average annual temperature of 9.3 degrees C. Within this experiment following growth regulators and fungicide with growth regulation effect were used: Retacel extra R68 (chlormequat chloride 720 g.l(-1)), Moddus (trinexapac-ethyl 250 g.l(-1)), Cerone (ethephon 480 g.l(-1)), Amistar (strobilurin 250 g.l(-1)). Approximately 2 and 4 weeks since the beginning of drought stress were carried out physiological measurements of chlorophyll and flavonoid content. From our preliminary results it can be concluded that under drought stress the decrease of chlorophyll content in leaves was found. Growth regulators CCC and trinexapac mitigate the decline of chlorophyll content caused by drought in the upper leaves but rather increased the impact in older (lower) leaves. Fungicide azoxystrobin alleviates the decrease of chlorophyll caused by drought in all leaves. The results show that the positive effect of regulators reducing the impact of drought on the parameter FV/FM was seen in all growth regulator treatments with the most significant effect of the active ingredience trinexapac-ethyl.