Introduction
Seed priming is a low-risk and straightforward seed treatment that improves seed germination
and seedling growth. Priming techniques include hydropriming, hormopriming, nutripriming,
biopriming, and osmopriming. This experiment involves the best priming method and how it
affects germination percentage and seedling growth. It is a pre-sowing seed preparation that
assists seeds to digest water and progress through the early stages of germination more
successfully.
Materials
Sterile distilled water, NaCl, PEG, GA, sodium hypochlorite, chili seed, beaker, petri dish,
filter paper, forceps.
Method
Preparation
1. For preparation, 0.05% NaOCl, 3% of NaCl (halopriming) and 200 ppm GA were
prepared. 0.05% NaOCl was prepared to rinse the seeds.
The formula M1V1=M2V2 was used to calculate the volume of NaOCl needed. M1V1
= M2V2, where M1 is the initial concentration, V1 is the initial volume, M2 is the
concentration after mixing or diluting, and V2 is the total final volume.
5.25%
5.25(V) = 0.05(50)
V= 2.5
= 2.5
5.25
V= 0.47 ml of NaOCl was needed for 50 ml solution.
3% of NaCl
3% of NaCl refers to 30g in 1L.
3g/100 ml of NaCl was prepared.
200 ppm GA
200 ppm is equal to 200 mg/L.
200 × 50 = 10 mg/50ml was prepared.
1000
2. 50 seeds were weighted for each treatment.
3. The seed was steriled with 0.05% of NaOCl for 5 min and then wash with sterile
distilled water.
4. For control, after sterilization, it was straight away germinated.
5. The seed was soaked in each treatment for 24 hr at room temperature in the dark.
Experiment
1. The seed was removed from priming solution.
2. The seed was dried at 25 oC for 24 hrs.
3. The dry seed was weighed (the seed must be as close as to its original weight).
4. The seed was germinated in the plate containing moist filter paper in the growth
chamber at 25 oC for 21 days.
5. On day 21, the length and fresh weight of the seedling were checked.
Result
Treatment
Giberelic
acid (GA)
Halopriming
(NaCl)
Control
Seedling
length (cm)
7.5
4.0
3.5
2.0
4.0
1.5
2.5
6.0
1.0
2.0
8.0
5.0
2.0
7.0
6.0
2.5
5.5
3.0
5.0
4.5
0.9
3.0
6.0
0.4
0.4
1.3
0.4
3.5
Total
Total of nonnumber of germinated
germinated
seeds
seeds
Germination
percentage
(%)
Seed
weight
(mg)
Seedling
fresh
weight
(mg)
after 21
days
44
6
88
277.3
260.2
33
17
66
167.2
364.5
10
18
35.71
460.4
170.9
Discussion
1. Which priming shows the best treatment? Explain your answer based on the scientific
reason and compare with previous studies.
Priming that shows the best treatment is Gibberellic Acid. Based from the result,
it is proven that priming seeds with Gibberellic Acid has the highest germination rate
than priming seeds with halopriming (NaCl) and control. As what is stated in previous
study, Gibberellic acid has been frequently utilized to promote seedling growth
(Chunthaburee et al., 2014). This is because seed priming with Gibberellic acid has
been shown to break seed dormancy by weakening endosperm layers and activating
embryo growth effectively compared to control and priming with NaCl (Pallaoro et al.,
2016).
On the other hand, seed priming with NaCl improves tissue tolerance and
protects photosynthetic ability of seeds (Paul et al., 2023). Therefore, the priming NaCl
results in higher germination rate compared to control but lower germination rate than
priming with Gibberellic Acid.
Not only that, based from the result the germination of Gibberellic acid priming
shows more uniform growth compared to priming with NaCl and control. The result of
priming with Gibberellic acid also shows more synchronized germination followed by
priming with NaCl and control.
Weight changes caused by priming are a result of the temporary hydration and
drying process. Based from the result, the seedling fresh weight of GA primed seed is
decrease in comparison to the initial weight whereas the seedling fresh weight in NaCl
is increase compared to its initial weight. This is because primed seeds in GA are dried
to a lower moisture content and in drying phase while seeds in NaCl is in hydration
phase that involves absorption of water and temporarily become heavier. Hence,
priming with Gibberellic acid is better than with NaCl because the speed of hydration
process is faster than primed in NaCl.
2. How priming can enhance seed germination compared to control?
Priming involves hydrate and rehydrate seeds. It does not allow full germination
(Savaedi et al., 2019). Priming is conducted in order to activate the pre-germinative
metabolism of the seed but also preventing germination. Priming usually involves
soaking seeds less than 24 hours and drying seeds back until the weight is similar as
original weight. As stated in previous research, seed priming not only enhances
germination rate and uniformity but also significantly improves plant growth and stress
resistance.
In control germination, seeds often germinate not in uniform germination.
Germination uniformity can vary under normal conditions, with some seeds
germinating earlier or later than others. Compared to priming seeds, they germinate in
a more synchronized emergence of seedlings. Hence, this is useful in agricultural
industry where uniform plant establishment is requested.
In addition, in control germination, seeds may expose to environmental stress
problems, potentially affecting germination success compared to primed seeds. They
are frequently more resistant to stress. The priming process causes biochemical and
molecular changes in the seedlings, making them more resilient to environmental
challenges.
Furthermore, control seeds may mobilise and utilise stored reserves not
efficiently, resulting in lower performance in energy utilisation for germination
compared to primed seeds. On the other hand, primed seeds result in good performance
in energy utilisation for germination process and early growth (Yamaguchi, 2008).
All in all, priming is a specialised technique used to improve and synchronise
the germination process, resulting in better seedling performance. It is especially
effective in cases when rapid and uniform germination is required, and it can provide
benefits in terms of stress tolerance and resource utilisation above standard
germination.
References
Anwar, M. P., Jahan, R., Rahman, M. R., Islam, A. K. M. M., & Uddin, F. M. J. (2021).
Seed priming for increased seed germination and enhanced seedling vigor of
winter rice. IOP Conference Series: Earth and Environmental Science, 756(1),
012047. https://doi.org/10.1088/1755-1315/756/1/012047
Chuntaburee, S., Sanitchon, J., Pattanagul, W., & Theerakulpisut, P. (2014). Alleviation
of Salt Stress in Seedlings of Black Glutinous Rice by Seed Priming with
Spermidine and Gibberellic Acid. Notulae Botanicae Horti Agrobotanici ClujNapoca, 42(2). https://doi.org/10.15835/nbha.42.2.9688
Farhan Jalees Ahmad, Kamal, A., Singh, A., Farha Ashfaque, Saud Alamri, Siddiqui,
M. H., & Iqbal, M. (2020). Seed priming with gibberellic acid induces high
salinity tolerance in Pisum sativum through antioxidants, secondary metabolites
and up‐regulation of antiporter genes. Plant Biology, 23(S1), 113–121.
https://doi.org/10.1111/plb.13187
Paul, A., Mondal, S., Pal, A., Biswas, S., Chakraborty, K., Mazumder, A., Biswas, A.,
& Kundu, R. K. (2023). Seed priming with NaCl helps to improve tissue
tolerance, potassium retention ability of plants, and protects the photosynthetic
ability in two different legumes, chickpea and lentil, under salt stress. Planta,
257(6). https://doi.org/10.1007/s00425-023-04150-y
Savaedi, Z., Parmoon, G., Moosavi, S. A., & Bakhshande, A. (2019). The role of light
and Gibberellic Acid on cardinal temperatures and thermal time required for
germination of Charnushka (Nigella sativa) seed. Industrial Crops and Products,
132, 140–149. https://doi.org/10.1016/j.indcrop.2019.02.025
Yamaguchi S. Gibberellin metabolism and its regulation. Annu. Rev. Plant Biol.
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