3.1. Effect of storage period and storage condition
3.1.1. Effect on final germination
Both storage period and storage conditions and their interactions
significantly affected final germination percentage of the
two species (P < 0.001, Table 1). Generally, storage in freezer didn’t
affect the level of final germination, compared to the other storage
conditions, especially seeds stored under natural field conditions.
The germination of fresh seeds was 76% and 68.3% in H. salicornicum
and S. imbricata, respectively. Storage for three months significantly
increased germination of seeds stored under different
conditions, compared to germination of fresh seeds. The range of
the germination increase was between 10.5% for seeds stored
under warm conditions and 22.8% for seeds stored in field
conditions in H. salicornicum and between 18.9% for seeds stored
in freezer and 37.4% for seeds stored under warm conditions in S.
imbricata.
In H. salicornicum, storage for nine and 12 months completely
inhibited germination of seeds stored in the field and significantly
reduced germination of seeds stored in warm and room temperature
conditions, but not affected germination of seeds stored in
freezer, compared to fresh seeds. Further storage for 17 months
led for almost complete inhibition in germination of seeds stored
in warm and room temperature conditions and to a significant
reduction for the germination of seeds stored in the freezer (Fig. 1a).
For S. imbricata, nine months storage inhibited germination of
field seeds, but not affect it for seeds stored under the other conditions.
Storage for 12 and 17 months significantly reduced final germination
of cold, room and warm storage seeds, but did not
completely deteriorate it. The deteriorations in final germination,
compared to fresh seeds, under warm, room temperature and cold
conditions were 32.6%, 21.1% and 17.2%, respectively, after
12 months and 60%, 55.4% and 27.7%, respectively, after 17 months
(Fig. 1b).
3.1.2. Effect on germination speed
Similar to the impact on final germination, both storage period
and storage conditions and their interactions significantly affected
final germination speed of the two species (P < 0.001, Table 1).
There was no significant difference in germination rate index
between fresh seeds and those stored for three months under different
conditions. Storage significantly increased germinate rate
index of seeds stored for nine months in all storage conditions,
except field seeds, which did not germinate. After 12 and
17 months, the increase in germination speed, compare to fresh
seeds, was significant for S. imbricata stored at the different conditions,
but was significant only for seeds of H. salicornicum stored in
freezer (Fig. 2). After 17 months, the germination rate index of H.
salicornicum seeds stored in room temperatures and warm conditions
was significantly low, compared to that of fresh seeds (Fig. 2a).
3.2. Effects of storage condition and temperature of incubation
3.2.1. Effect on final germination
The effects of storage condition and temperature of incubation
and their interaction on final germination were significant in both