Investigation of the effect of salicylic acid appilication on some parameters related to plant development in sunflower (Helianthus annuus L.) Plants under salt stress

This study was carried out to determine the effects of salicylic acid application on some plant development parameters in sunflower (Helianthus annuus L.) grown under salt stress. The research was established as a pot experiment in Siirt University, Faculty of Agriculture, Field Crops Laboratory in 2024. PL64LP130 sunflower variety was used as material. Different salicylic acid doses (0, 0,25 mM, 0,50 mM, 0,75 mM and 1,0 mM) were applied to the plants and salt stress levels (0 mM, 75 mM, 150 mM 225 mM and 300 mM NaCl) were created. The experiment was arranged according to the factorial trial design in randomized blocks with four replications. In the research, developmental parameters such as plant height, stem thickness, leaf number, root length, root thickness, fresh and dry plant weight, chlorophyll ratio and ion analysis were measured and the obtained data were statistically analyzed. According to the results obtained, increased salt stress negatively affected plant development, but salicylic acid applications significantly reduced these negative effects. As a result, it was determined that salicylic acid application could be effective in increasing the tolerance of sunflower plants to salt stress. These findings show that the use of salicylic acid in appropriate doses, especially for sunflower cultivation in saline soils, can help reduce yield losses. It is recommended that similar applications be tested under different plant varieties and stress conditions in future studies.