Abstract:
Stevia (Stevia
rebaudiana Bertoni), with great potential as
a natural sweeteners source, has a high
content of sweeteners, which are up to 150
times sweeter than sugar, but virtually with
no calories. Stevia also suitable to be
cultivated in semiarid climates and coastal
areas, which are characterized by the low
quality of the irrigation water. Soil salinity
occupies a prominent place among the soil
problems that threaten the sustainability of
agriculture over a vast area in the world.
Glycine betaine is an osmoprotectant, that
plays an important role and accumulates
rapidly in many plants during salinity or
drought stress. In order to evaluation of
glycine betaine amending effects on salinity
stress in stevia under in vitro condition, a
factorial experiment was conducted in 2015.
Four NaCl levels, including 0, 50, 75 and
100 mM, along with 0, 1, 12.5, 25 and 50
mM of glycine betaine concentrations were
used in Murashige and Skoog (MS)
medium. The results showed that salinity
levels had significant reduction effects on
plant height, root length, shoot fresh weight,
number of leaf, total chlorophyll,
rebaudioside A and stevioside of the stevia
genotype. Due to increasing of glycine
betaine, levels all the traits were increased.
Owing to amending effect of glycine
betaine, its high concentrations made less
hazarding effects of salinity on the
researched traits. The highest mean value of
rebaudioside A (10.62rt) and stevioside
(23.38rt) determined at 50 mM of glycine
betaine with 0 mM of NaCl concentration.
