The effects of various planting density, cutting times and cutting numbers on yield and quality of Stevia rebaudiana in Çukurova conditions

This study was conducted at the experimental area of Field Crops Department, Agricultural Faculty of Çukurova University in 2013 to determine the effect of various planting density (30×60, 45×60 and 60×60 cm), different cutting times and cutting numbers on yield and quality of Stevia rebaudiana Bertoni. Field trials was arranged in split split plot and randomized complete blocks with three replications. The plant density, cutting times and cutting numbers were as main, sub and sub-sub plots respectively. According to the results, the highest plant height, stem number, stem diameter, fresh and dry herb, stem and leaf yield, inflorescence number, fresh and dry inflorescence yield and seed yield were determined in 30×60 cm planting density. In terms of cutting time, the highest plant height, stem number, stem diameter, fresh and dry herb, stem and leaf yield were obtained from flowering stage and the highest leaf/stem ratio was obtained from preflowering stage. Also, the highes stem diameter, fresh and dry herb, stem and leaf yield and leaf yield were determined at first cuttings and stem number, inflorescence number, fresh and dry inflorescence yield and seed yield were determined at second cuttings. The highest dry leaves Stevioside ratio were was identified in 30×60 cm planting density, preflowering stage and 2nd cuttings. In terms of the other dry leaves sugar components, the highest Sucrose, glucose and fructose were found in second cuttings and sorbitol was found in first cuttings. In this study, the highest yield in Cukurova region for the Stevia rebaudiana Bertoni, which is a potential non-calorie sweetener used for remedy of hypertension and hyperglycemic patients, was obtained in 30×60 cm planting density and preflowering stage.