الفهرس 
REVIEW OF LITERATURE
Statistical analysisOnly 14 pages are availabe for public view
 |  | from | 435 |  |  |
| | | from | 435 | | |
Abstract
The objected of the present work is to improve chilling and
salinity stress tolerance of coriander plant (Coriandrum
sativum L.) by priming the seeds in potassium silicate (80
mM), humic acid (50 mg l-1). Radiation treatment (50 Gy) was
carried out using cesium-137, dose rate 0.758rad/sec. The
irradiated seeds were then soaked in tap water. Untreated seeed
were soaked in tap water (control).
For chilling treatments, all above mentioned treatments were
preserved in room temperature (20 ºC ±2) or in incubator at (6
ºC ± 0.5) for 16 h. However, in chilling stress, the seeds after
treatment with silicate, HA or gamma radiation were sown in
pots (30cm diameter) filled with 15 Kg clay: sand soil (2:1).
Each pot contained ten seeds. The pots were divided into two
groups, one of them was irrigated with tape water while, the
other group irrigated 4times with 150mM NaCl at 20, 27,
34and 40 days after sowing.
The effect of chilling stress(6 ºC ± 0.5) alone or in combination
with the alleviator agents (Experiment I) and the effect of salt stress ) alone or in combination with the same alleviator
agents(Experiment II) on the growth parameters at early
vegetative stage, vegetative stage and flowering stage , yield
and yield components at harvesting were determined.
In addition, endogenous phytohormones , photosynthetic
pigments ,carbohydrate contents, nitrogen constituents ,
mineral ions content ,antioxidant compounds ( ascorbic acid ,
carotenoids , flavonoids , total phenols and proline ) ,
antioxidant enzymes (PPO, POD , CAT ) polyamines
(putrescine, spermidine , spermine and total ) , amino acid
composition ,fatty acid composition , and lipid peroxidation
were also investigated total volatile oil content and
composition were also determined.
The obtained results proved the crosstalk between chilling
stress and salinity stress through either the reduction in growth
parameters , yield components IAA , GA3 contents
photosynthetic pigments , polysaccharides content , soluble –
N ,mineral ions ( K ,Mg , Ca ) or the increase in ABA soluble
sugars , protein – N total – N , Na ion lipid peroxidation
(MDA) polyamines , total free amino acids and the unsaturated
/ saturate fatty acids ratio and antioxidant enzymes (PPO ,
POD and CAT ) activities .
In addition, protein band at 53 KDa was identified as the large
subunit of RuBisCO in all samples of control stressed coriander
plants and chilling – stressed alleviated ones and salinity –
stressed alleviated plants. Chloroplast channel protein (Toc75)
was negatively affected by chilling and salinity stresses
Expression of ADC was not affected by chilling or salinity
stress.
Application of potassium silicate , humic acid or gamma
radiation activities has promotive effect on growth parameters
biochemical activities and yield characteristic of coriander plant under normal condition or in combination with either
chilling or salinity stress . These chemicals could alleviate the
adverse effect of both chilling and salt stress by improving the
nutritional value and the oil quality coriander plant through
increasing linoleic acid ( Omega 6) , linolenic acid (omega 3 )
and oleic acid ( Omega 9 ) contents in inflorescence and leaves
the most effective chemical in alleviating the chilling stress in
coriander plant is humic acid followed by silicate however the
preferable chemical in alleviating salt stress is silicate followed
by humic acid and then gamma radiation .
Key works:
Coriandrum sativum L., coriander, Chilling stress, salt stress,
growth, yield, phytohormones, antioxidant enzymes,
antioxidant compounds, fatty acids, amino acids, volatile oil,
SDS-PAGE, DOT- BLOT technique.