Genomics and Applied Biology 2018, Vol.9, No.2, 6-13
7
There are many kinds of GA, such as GA1, GA3, GA7, etc., it could effectively eliminate the dormancy of seeds,
roots and buds, increase the content of IAA, promote cell division, induce synthesis α-amylase, speed up the
starch hydrolysis in endosperm, and then, break seed dormancy. In this way, it could promote the germination of
seed and the elongation of stem, and also facilitate the forming of male flower, plant blossoms, meanwhile
promote the germination of seed (Wang et al., 2017). GA1, GA3, GA4, contained 3β-OH groups, so it had high
bioactivity. And GA3 had the highest bioactivity among them, and it was the most widely used kind (Li D.L.,
2013), which could improve the growth of seed and fruit, inhibit maturation, inhibit the dormancy and the
senescence of lateral buds, as well as the formation of tuber (Pan et al., 2006). The research, which studied the
germination effects of plant hormone (eg: IAA, 6-BA, GA3, etc.) and plant growth regulators on wheat seeds
showed that GA3 might have optimal effects on improving the germination of seeds, but the germination rate was
low and without the growth conditions of the plant after germination.
The application of GA was an ideal way to break seed dormancy in view of the wide spread and practicability of
agriculture. But now, there was little research had been done to study the seeds of
Sophora davidii
with GA. In
this study, the
Sophora davidii
seeds were treated by GA with different concentrations for different times. Then we
measured physiological and biochemical indexes of the
Sophora davidii
seeds, as well as the sites of water
absorption. This study aimed to clarify the effect on the growth conditions of roots and the seed germination by
GA3 with different concentrations.
1 Results and Analyses
1.1 Morphological characteristics of
Sophora davidii
seeds
By observing the whole and anatomical map of the
Sophora davidii
seeds under anatomic microscope and
recording the data, we can see that the seed of
Sophora davidii
is smaller and the seed coat is thicker (Table 1).
The volume and quality of
Sophora davidii
seeds were relatively small which indicated that the injected-water
volume was smaller and the seed coat was thicker, meanwhile, it would be the barrier to the absorption of water
and gas exchange, and had bound effect on germination of seeds.
Table 1 Quality, length, width, thickness and seed coat thickness of
Sophora davidii
seeds
Seed length(mm)
Seed width (mm)
Seed thickness (mm) Seed radius (mm) Seed quality (mg) Seed coat thickness (mm)
3.65±0.12
2.62±0.07
2.42±0.13
2.90±0.21
1.63±0.22
0.0853±0.0093
1.2 The effect on germination rates of
Sophora davidii
seeds treated by GAwith different concentrations
The polishing group and unfinished group treated by GA3 with the same concentration gradient under the same
condition were observed, from which we found the significant difference of germination rates. Took the seeds
treated by GA3 with 200 mg/L and 500 mg/L concentration as an example. The germination rate of polishing
group treated by GA3 up to 51% on the 3
th
day, and the lowest rate was 32%; meanwhile, the group treated by
GA3 without polishing started to sprout on the 5
th
day. Compared the state of seeds treated by GA3 in two groups
with the control group, we found the seeds treated by GA3 which sprouted on the1
st
day and 5
th
day was earlier
than the seeds in control group which sprouted on the2
nd
day and 8
th
day. In the polishing group treated by GA3,
GA3 with 200 mg/L concentration showed the biggest accelerating effect for seed germination. In the group
without polishing treated by GA3, 100 mg/L concentration showed the biggest accelerating effect for seed
germination (Figure 1; Figure 2).
Compared with the control group treated with vaseline seal, the germination rate of unsealed group was 38.46%
from the beginning of germination to the 4
th
day. However, from 5
th
day to 13
th
day, the maximum germination
rate of every group except sealing raphe and hilum was 53.33%, which was higher than no sealing control group.
The lowest germination rates of sealing raphe and hilum groups showed that raphe and hilum couldplay a big part
in the water absorption and the germination of seeds. But there was a higher germination rate after sealing raphe
and a lower germination rate after sealing hilum, which showed that the main water absorption site was raphe. In
