Effects of chitosan application on the yield and quality of lettuce

Modern agricultural production has adopted the principle of maximizing yields in an environmental-friendly, inexpensive, and non-hazardous way. With these characteristics, chitosan has become an increasingly preferred biostimulant in sustainable agriculture. The aim of this study was to determine the effects of chitosan application on yield and quality in lettuce cultivation. For this purpose, Yedikule 5107 lettuce variety was used, and foliar chitosan applications were applied 3 times at 4 different doses of 0, 75, 150, and 300 ppm levels. The total yield, leaf number, leaf width, chlorophyll, total phenolic, and antiradical activity values ranged from 2970 to 3290 kg da-1, from 35.8 to 37.7, from 11.27 to 12.33 cm, from 38.05 to 41.82, from 21.50 to 38.71 mg/100 g, and 46.0% to 54.9%, respectively, and the highest values were obtained in the 300 ppm chitosan application. The highest root collar and plant diameter values were determined at 75 ppm and 150 ppm chitosan doses, respectively. All chitosan applications increased leaf length. Furthermore, chitosan applications were effective in preventing nitrate accumulation. In conclusion, it was determined that the effect of pre-harvest chitosan application was positive, and especially 300 ppm chitosan dose was more effective than other doses.