Effect of Trinexapac-ethyl and Traffic stress on morphological and physiological traits of tall fescue cultivar Rebel

Application of growth reterdants such as trinexapac-ethyl has become popular in turf grass management. The principle goal to apply these substances is to reduce lawn vertical growth, prevent inflorescence development and increasing biotic and abiotic tolerance. The aim of the present research wasto investigatethe effect of different trinexapac-ethyl levels (0, 0.25 and 0.5 Kg/h) and traffic stress on morphological and physiological traits of tall fescue cultivar Rebel. Experiment was carried out as a factorial based on completely randomized design in three replicates. Results showed that trinexapac-ethyl and traffic significantly decreased height, dry and fresh weight. Growth reduction in 0.25 and 0.5 Kg/h of trinexapac-ethyl was about 18.84 and 22.06%, respectively. Trinexapac-ethyl application led to increase density, tillering and chlorophyll, amount while traffic treatment reduced relative chlorophyll amount, density and tillering, significantly. Its application at concentration of 0.5 Kg/h increased tillering about 36% and traffic stress reduced it about 17.2%. Results also indicated that, trinexapac-ethyl and traffic treatment increased shoots soluble carbohydrates, significantly, whereas this substance did not affect root soluble carbohydrates in comparison to traffic. Trinexapac-ethyl increased tall fescue traffic stress resistance by increasing relative water content and decreasing electrolyte leakage in traffic stress conditions.