Abstract:
Drought is still accounted as a serious agronomic p
roblem and also one of the most
important factors contributing to crop yield loss.
The effect of sodium silicate (Na
2
SiO
3
,
abbreviated as Si) was investigated on the four maj
or antioxidant enzyme activities and
five other relevant components in two different gra
pevine cultivars (
Vitis vinifera
L., cvs
Mish Pestan and Sahebi, as tolerant and sensitive c
ultivars) under drought stress. The
experiment was performed in a completely randomized
design including three treatments
i.e. the control, drought with no Si, and Si-drough
t (0.004M sodium silicate kg
-1
soil), with
three replications in a greenhouse. The results ind
icated that Si partially offset the
negative impacts of drought stress by increasing th
e tolerance of grapevine by rising
antioxidant enzyme activities and soluble protein c
ontent. Si treatment significantly
affected the enzyme activities in both cultivars. W
ater stress induced a decrease in total
Chlorophyll (Chl) and total protein contents, which
was much larger in no-Si stress than
in Si treatment. The results indicated that sodium
silicate might decrease drought stress
damages by raising the antioxidant enzymes activity
.
Keywords
: Antioxidant enzymes, Drought stress, Grapevine, S
ilicon.
