Investigation of the effect of salicylic acid doses on drought resistance in lettuce plants in the Southeast Anatolia Region

This study was conducted in 2019 to examine the effect of drought resistance of salicylic acid doses on lettuce plants in Diyarbakır province. The main subjects of the experiment are 3 (three) different irrigation water amount (100% (I1), 75% (I2), 50% (I3) of the accumulated water evaporating from the class A evaporation pan), and the subtopics of the experiment 4 (four) different doses of salicylic acid (SA1) (0 mM (SA1), 0.25 mM (SA2), 0.5 mM (SA3) and 0.75 mM (SA4)). Depending on the different amounts of irrigation water use in the study and different doses of SA, lettuce plant yields varied between 442.33 - 650.20 g plant-1. The highest yield of lettuce plant was 650.20 g plant-1 obtained from where 100% of the evaporation of irrigation water from class A evaporation pan and SA dose was applied as 0.50 mM. According to the applications, , the highest lettuce plant height value was 26.52 cm and it was obtained from the I1SA1 where 100% of the evaporation amount of irrigation water from class A pan was applied and SA was not applied. The highest plant width value was obtained from I1SA3 subject with 14.06 cm. According to the experimental subjects, the highest number of leaves was obtained from the I1SA4 interaction of the subject I1, where 100% of the evaporation from class A evaporation pan was given, and the subject SA4, where SA was applied as 0.75 mM. In general, the increase in the amount of irrigation water and the increase in SA doses had a positive effect on the parameters examined. Lettuce is a sensitive plant that reacts very quickly to dry conditions due to its physiology. In this study, it was determined that the increase in the amount of irrigation water and the increase in the SA application dose, which gives resistance to drought, positively affected the yield, yield elements and quality.