The Effect of Different Plant Population and Plant Age on Some Yield and Quality Parameters of Sugar Grass (Stevia Rebaudiana Bertoni L.)

This study was established in 2017 and 2018 to determine the yield and quality parameters of sugar grass (Stevia rebaudiana Bertoni L.) at different plant densities (25x50, 30×50, 35x50, 40×50 cm) and number of harvesting (1st harvest and 2nd harvest). The experiment was carried out according to ‘split plots experimental design’ with 4 replications. Fresh herb yield, dry herb yield, stevioside (steviol glycoside) ratio, different sugar components in leaves, rebaudioside A, B and C (Reb A, Reb C, Reb D) were analysed. As a result, the highest fresh herb yield was obtained at 25x50 cm plant density with 502.33 kg/da and 417.90 kg/da in the first and second year, respectively in the 2nd form, while the lowest fresh herb yield was obtained at 40x50 cm plant density in the 1st form with 129.99 kg/da and 223.76 kg/da, respectively. The highest dry herb yield was obtained in the first and second year with 150,32 kg/da and 164,50 kg/da at 25x50 cm plant density in the 2nd form, and the lowest dry herb yield was obtained with 37,12 kg/da and 69,93 kg/da at 40x50 cm plant density in the 1st form. Stevioside ratios were between 7.47 and 5.71 in the first year and between 7.69 and 6.58 in the second year, the amounts of different sugar components in the leaves were between 13.27 mg/ml and 10.37 mg/ml in the first year and between 13.47 mg/ml and 10.85 mg/ml in the second year, RebaudiosideA ratios were between 13.27 mg/ml and 10.37 mg/ml in the first year and between 13.47 mg/ml and 10.85 mg/ml in the second year, 09 to 2.39 in the first year and 3.20 to 2.58 in the second year, RebaudiosideC rates varied between 1.00 and 0.76 in the first year and between 1.15 and 0.76 in the second year, and RebaudiosideD rates varied between 1.56 and 1.07 in the first year and between 1.56 and 0.00 in the second year. According to the results of the two-year study, it was determined that frequent planting, especially 25x50 cm planting frequency, gave better results in Hayrat district conditions.