2022, Vol. 10, Issue 2, Part B

author(s)
Mohamed A Abd El-Wahab, Moustafa YM Badawy, Wafaa H Abd El-Aleem and Saber M Bakeer

abstract
Stevia as a sweetener substitute for sugar represents a significant impact on human health, especially on diabetics and children, which prompts finding a way to improve and increase its productivity with high quality. In this study, two Stevia cultivars were grown in more than cultivation media under hydroponic conditions to obtain the highest yield of dry leaves and the highest content of sweeteners. The experiment was laid out according to a split-plot arrangement. Cultivation media was kept in the main plot, whereas Stevia cultivars were randomized in sub-plots. The first factor of the hydroponic planting media was that six different mixtures of different agricultural soils such as sand, silica, perlite, peat moss, and vermiculite were used as treatments from S1 to S6. The second factor was two varieties of stevia, Stevia rebaudiana, cv Sugar High-A3 (V₁), and Stevia rebaudiana, cv Morita (V₂). The results indicated that cultivation media had an influence very evident on plant height, number of branches/plant, leaf fresh weight/plant, leaf fresh weight/m2, dry weight/plant, and leaf dry weight/m2. The highest values were recorded with the S6 treatment (sand + perlite + peat moss), especially with Stevia rebaudiana, cv Morita, and S5 (sand + perlite + peat moss + vermiculite), especially with Stevia rebaudiana, cv Sugar High-A3. Concerning the effect of varieties, the superiority of Stevia rebaudiana, cv Morita over Stevia rebaudiana, cv Sugar High-A3 was noticed in all vegetative measurements, especially the yield of fresh and dry leaves and the content of stevioside in leaves. Regarding the interaction between cultivation media and varieties of stevia, the best treatment was cultivating Stevia rebaudiana, cv Morita in media containing sand, perlite, and peat moss (V₂S₆) to produce the highest yields of fresh and dry leaf regularly in all cuts. Also, using S₃ (sand+ silica+ perlite + peat moss + vermiculite) led to obtaining the highest content of sweeteners in the two varieties, especially the stevioside.