Abstract:
Saline stress is one of the
most deleterious abiotic stress determining a
considerable reduction in agricultural
production. Seed germination is the
primitive plant growth stage and considered
as vulnerable to saline stress. However, the
exogenous application of natural plant
growth regulators has been reported as one
of the mitigation strategies. A Petri dish
experiment under controlled conditions was
conducted at King Saud University. The aim
was to quantify the negative impact of
induced saline stress (NaCl) on seed
germination attributes and role of
gibberellic acid (GA3) and salicylic acid
(SA) to reduce the inhibitory effect of
saline stress on cucumber (Cucumis sativus
L.) seeds. The treatments consist of two sets
as: seed pre-soaking solution and NaCl
stress. Five pre-soaking solutions were
prepared as: H2O (control), GA3 (100 ppm),
GA3 (200 ppm), SA (0.5 ppm) and
SA (1.0 ppm). While saline stress was
imposed by NaCl at three levels such as: no
stress (distilled water, control), mild stress
(NaCl, 50 mM) and higher stress (NaCl,
100 mM). Results depicted that NaCl
induced stress has significantly affected the
all studied germinations attributes. The
maximum NaCl stress (100 mM) stood
highest in inhibiting seed germination
percentage, seedling length, and seedling
fresh and dry weights, followed by mild
stress and control, respectively. Seed presoaking
treatments were recorded nonsignificant
for seedling length, fresh and dry
weights while significant for germination
percentage and number of seeds germinated
over period of time. The interaction between
seed pre-soaking treatments and induced
saline stress was recorded significant.
Overall, GA3 at the rate of 100 ppm
solution performed a contributory role to
mitigate the negative effect of saline stress.
