The 6th International Mediterranean Symposium on Medicinal and Aromatic Plants (MESMAP-6), İzmir, Turkey, 15 - 17 October 2020, pp.107-119
Objectives: Stevia rebaudiana Bertoni (stevia, sweetleaf, sugarleaf) is the homeland of South America,
was discovered in 1887 by a South American natural scientist, Antonio Bertoni. S. rebaudiana is
member of Asteraceae family which likes moist conditions, temperatures mean 25°C and grows up to
60-90cm high. The plant, detected 79 species in North America is stated to be found more than 200
species in South America. The main components of stevia extract is stevioside, rebaudioside-A and
steviol molecules. The stevia plant is known to have been used as a source of sugar by the locals for
centuries. Dried form of stevia leaves is 10-15 times sweeter than sugar and the glycoside extract
obtained by purification from the stevia plant is 200-300 times sweeter than refined sugar. The existence
of some research, showing that non-calorie stevia plant does not increase blood sugar levels, has an
effect on increasing insulin sensitivity and even insulin secretion, lend support its use in the treatment
of diabetes. With this research, it was aimed to determine the favourable genotype or genotypes and the
appropriate sowing frequency by investigating the adaptation of Stevia rebaudiana, Stevia rebaudiana
Candy and Stevia rebaudiana Organic genotypes, imported as an introduction material, for Antalya
plain conditions. Methods: Compared with the varieties used in the research, Stevia rebaudiana Candy
genotype comes to the fore in terms of single plant dry leaf weight and rebaudioside-A/stevioside ratio
which is an important quality criterion. While there was no significant difference in
rebaudiosideA/stevioside ratios from three different plant densities (30x30cm, 40x40cm and 50x50cm)
applied in the experiment, single plant/herb, fresh leaf and dry leaf weights were found high in 50x50cm
application. Results: Considering the number of plants in the unit area, the yield per decare is higher
with the application of 30x30cm, but as the plant density increases, the risk of fungal disease increases
depending on the temperature and humidity. Conclusion: When the features which are examined are
taken into consideration; Plant height, number of side branches, single plant dry leaf weight values vary
depending on year, application and genotype. The values of single plant fresh herb weight and single
plant age leaf weight vary depending on application and year. Rebaudioside-A content varies depending
on the genotype, stevioside content and rebaudioside-A/stevioside ratio.