The effect of different plant density and harvesting number on the yield and quality parameters of sugarleaf (Stevia rebaudiana bertoni L.) in Rize conditions

THE EFFECT OF DIFFERENT PLANT DENSITY AND HARVESTING NUMBER ON THE YIELD AND QUALITY PARAMETERS OF SUGARLEAF (Stevia rebaudiana Bertoni L.) IN RİZE CONDITIONS ABSTRACT This study was established in order to determine yield and quality parameters of sugarleaf (Stevia rebaudiana Bertoni L.) harvesting numbers at different plant densities (25x50, 30×50, 35x50, 40 × 50 cm) in 2017. The experiment was carried out with 4 replications according to the "split plots trial pattern''. In the research, the plant density, number of branches, green herba weight, green leaf weight, dry leaf weight, green leaf yield, green herba yield, dry herba yield, dry leaf yield, fresh leaf yield, branch weight, fresh branch yield, dry branch weight, dry branch yield, fresh leaf / fresh stalk ratio, dry leaf / stalk ratio, number of inflorescences per plant, seed weight per plant, seed yield, thousand seed weight and stevioside (steviol) glycoside) ratio etc. characteristics of sugarleaf were investigated. As a result; the highest plant length average of 82.31 cm and 25x50 cm plant density in the 2nd form, the lowest plant height in the first form 57.31 cm and 30x50 cm plant density was determined. The maximum number of branches per plant in the 2nd arvesting is 13.88 / plant average with a plant density of 25x50 cm while the minimum number of branches per plant in the first harvesting is 1.71 pcs / plant with average again in 25x50 cm plant density was obtained. The highest yield of fresh herba in the 2nd harvest was obtained with 502.32 kg / da at 25x50 cm plant density, While yield of fresh herba at least 129.99 kg / da with a plant density of 40x50 cm was obtained in the first harvest. Maximum dry herba yield 150.32 kg / da with 25x50 cm plant density in the 2nd harvesting, at least dry herba yield 37.12 kg / ha with a plant density of 40x50 cm was obtained in the first harvesting. Maximum fresh leaf yield in the first harvesting 192.68 kg / da with a plant density of 25x50 cm, at least fresh leaf yield was determined as 83.12 kg / da with a density of 40x50 cm. The highest dry leaf yield 57.34 kg / da with 25x50 cm planting density in the first harvesting, dry leaf yield at least 23.56 kg / da 40x50cm planting density was obtained in the first harvesting. Stevioside rate is highest with 40x50 cm plant density with 7.68% in 2nd harvesting, at least 5.71% with a plant density of 40x50 cm was obtained in the first harvesting. RebaudiosideA ratio with the highest 40x50 cm plant density in the second harvesting with 3.09%, at least 35x50 cm plant density 1. form 2.39% were obtained. According to the results of one year study, 25x50 cm plant density was found to give better results in Hayrat district conditions.