RJOAS, 9(129), September 2022

UDC 633; DOI 10.18551/rjoas.2022-09.11

EFFECT OF SEED PRIMING AGENTS (GA3, PEG, HYDROPRIMING) IN THE EARLY

DEVELOPMENT OF MAIZE

Supral Adhikari*, Roshan Subedi

Tribhuvan University, Nepal
*E-mail: supraladhikari7@gmail.com

ABSTRACT
Maize (Zea mays), the second most staple crop in Nepal is predominantly cultivated in the
hills during the spring and summer, thus, facing moisture stress during the early seedling
stages. Seed priming has proved to be an effective technique to resolve the issue. Early
development response of maize due to eight different seed priming levels viz. hydropriming,
three PEG concentrations (10%, 15%, 20%), three GA3 concentrations (50 ppm, 75 ppm,
100 ppm) and control exposed to non-stress and stress environment using 10% PEG was
studied in a two-factor factorial CRD replicated thrice. The study was conducted in the
Agronomy Laboratory of Lamjung Campus. GA3 was effective in improving the germination
percentage with 91.6% germination at 100 ppm. However, under the stressful environment,
there was a significant 16% reduction in germination. GA3 @ 50 ppm had the lowest mean
germination time (MGT) under the non-stress environment, while, increased GA3
concentration resulted in quicker germination under the stress environment. A similar trend of
increased concentration favoring quicker germination was observed for PEG as well. Non-
stress environment showed a balanced root: shoot ratio (1.00) while the stress environment
increased the R:S ratio (1.51) considering the progressive increase in root development
under stress. The lowest SVI was observed in the seeds treated with 20% PEG in both
environments. GA3 priming has a better impact on germination under stress environment for
its effect in countering the germination inhibitors and accelerating the metabolic plasticity
over the osmotic adjustments provided by PEG-priming.

KEY WORDS
GA3, PEG, metabolic plasticity, osmotic adjustment, seed priming, water-stress.

Maize is the second most important principle food crop in Nepalese agriculture both in
terms of area and production (Karki et al., 2015). During spring and summer planting of
maize, germination, and plant foundation is compromised due to moisture deficit, especially
in arid and semi-arid regions, which leads to the use of increased seed requirement as
insurance for optimal plant population. Germination plays an important role in the successful
growth and seedling development of a new plant (Wolny et al., 2018). Faster and uniform
germination of healthy seedlings signifies successful plant establishment (El-Sanatawy et al.,
2021). The delayed or very early sowing of maize outturns to the retarded or no germination
due to differences in optimum temperatures required for the maize seeds (Shrestha et al.,
2018). Although all the conditions like imbibition, respiration, synthesis of nucleic acids/
proteins, and other metabolic activities are completed; there is no protrusion of the radicle;
for which still the reasons are not scientifically clarified. Such dormant seeds can be changed
into germinable seeds by priming technique (Bewley and Black, 1994). Seed priming is an
economic pre-sowing treatment that allows partial hydration to carry out all the metabolic
activities before germination and then redried to the initial dry weight (Ur Rehman et al.,
2011). Seed priming not only improves germination and better seedling establishment but
also helps to reduce fertilizer use and increases seed vigor (Carvalho et al., 2011;
Ghassemi-Golezani et al., 2012; Laware et al., 2018). Priming with Polyethylene Glycol
(PEG) was proved to be effective for ameliorating seed germination and plant establishment
(Zhang et al., 2015). Priming with PEG decreased the mean germination time while
significantly increasing the leaf surface area along with the other plant growth parameters
(Salah et al., 2015). PEG priming has improved the rate, speed, and energy of germination

113
 RJOAS, 9(129), September 2022

compared to non-primed seeds but 5% PEG priming showed better performance than 10%
PEG priming (Subedi et al., 2015). In maize seeds, the rate of imbibition was greater in PEG
priming than in hydropriming while 15% PEG priming showed increased root and shoot
biomass with a significant increase in hundred-grain weight (Tian et al., 2014). Osmo-priming
with PEG significantly enhanced the germination percentage, germination rate, shoot length
and shoot fresh and dry weights compared to control when experimented in fields
(Mirmazloum et al., 2020). PEG priming enhances root length and can maintain uniform
water potential; also it speeds up the rate of imbibition, enhances seed metabolism and
germination rate, and maintains germination homogeneity (Laware et al., 2018). As a plant
growth regulator hormone, gibberellic acid (GA3) has many advantageous results on seed
germination, stem prolongation, foliar growth, and flowering initiation (Cornea-Cipcigan et al.,
2020). GA3 priming significantly increased germination percentage, root and shoot lengths,
seedling vigor index, and relative water content while decreasing the mean germination time
as compared to control (Gnawali & Subedi, 2021). Gibberellic acid treatment increased the
root and shoot length along with leaf length and width compared to untreated seeds.
Gibberellic acid both priming and foliar application was proved to be the most effective
method for the overall growth and development of maize under salt-stressed conditions
(Shahzad et al., 2021). Gibberellic acid treatment significantly increased the germination
rates, plant height, and biomass; subsequently enhancing the production (Ma et al., 2018).
The objective of the experiment is to assess the impacts of hydropriming, various
concentrations of polyethylene glycol and gibberellic acid priming in maize under water
abundant and PEG 10% stressed environment in controlled laboratory conditions.

MATERIALS AND METHODS OF RESEARCH

The research was conducted in the Agronomy laboratory of the Institute of Agriculture
and Animal Science (IAAS), Lamjung Campus located at 28.1448° N, 84.4120° E. 960 maize
seeds of variety Arun-4 were collected from the Maize Research Station, Rampur, Chitwan.
Surface sterilization was conducted using 95% ethanol for all types of equipment used before
the initiation of the experiment. 96 Petri dishes of 12 cm diameter and the germination
chamber (PRC 1200 WL) were used for the lab trials. The experiment was conducted in a
two-factorial design with two factors (priming agents and environments) in a completely
randomized design (CRD) replicated thrice. The priming reagents were control (unprimed),
hydropriming, 10% PEG solution, 15% PEG solution, 20% PEG solution, 50 ppm GA3
solution, 75 ppm GA3 solution, and 100 ppm GA3 solution. The environments were hydration
(water abundant) and 10% PEG solution (induced water stress environment). Twenty maize
seeds were used in every petri dish in three concentric circles (13 in outer circles, 6 in inner,
and one in the center). The Petri dishes and pots were moisturized or irrigated during the
one-day interval. Each Petri dish was rinsed with its respective environment solution to wet
the filter paper at the base to be neither dry nor get excess water on the Petri dish. Seed
germination was recorded on the daily basis. A seed was considered germinated if the
radicle emergence was 5mm. Germination was carried out in the germination chamber at
24±10C. A one-foot scale was used to measure the root and shoot lengths after one simple
washing with the tap water. Plant weights were evaluated by using an electric laboratory
weighing balance. Tap water is poured and left for 24 hours in the Petri plates to measure
the turgor weight while plants are subjected to an oven at 720C for 24 hours to measure the
dry weight. Data analysis was conducted using MS Excel 2019 and R (version 4.1.0). The
analysis of variance was carried out and the means were compared using Duncan's multiple
range test.
The 'environments' term here refers to the moisturizing/irrigating reagents used in the
experiment. There are two moisturizing reagents (hydration (water abundant) and 10% PEG
solution (water stress environment)) used in the Petri- dishes which are the two
environments. 10% solution of PEG was prepared by pouring 100gm of PEG 6000 in 1 liter
of water for the preparation and normal tap water is used as the water abundant
environment.

114
 RJOAS, 9(129), September 2022

Normal tap water was used for hydropriming. The three solutions of PEG were
prepared by pouring 100gm, 150gm, and 200 gm of PEG 6000 in 1 liter of water for the
preparation of 10%, 15%, and 20% of PEG solutions respectively. Firstly, a stock solution of
5000 ppm gibberellic acid was prepared; by pouring 5 gm of gibberellic acid powder in
ethanol to dissolve completely then making thus prepared solution 1 liter by the additional
pouring of water. From the stock solution of 5000 ppm; 10 ml, 15 ml, and 20 ml of GA3
solution were extracted differently by the pipette and made 1/1-liter solution by pouring
additional water into three beakers to prepare 50 ppm, 75 ppm, and 100 ppm GA3 solutions
respectively.
Research parameters:
1. Germination percentage: Germination percentage was calculated according to Scott
et al. (1984) and Ahammad et al. (2014):
The total number of seeds germinated
Germination percentage = ∗ 100% (1)
Total number of planted seeds

2. Mean Germination Time: Mean germination time was calculated as per the formula
given by Orchard (1977):
∑ 𝑓𝑥
MGT= ∑𝑓
(2)

Where: MGT - Mean Germination Time; f - Number of seeds germinated in ‘x’ days.
3. Root- shoot ratio: Root and shoot lengths were measured by using a simple one-foot
scale and measured in centimeters (cm) on the eighth day of the experiment and the ratio
was obtained.
4. Seedling Vigor Index II: Seedling Vigor Index II was calculated by using the following
formulae Anderson (1973) as stated in Anupama et al. (2014):

SVI II= DW* GP (3)

Where: SVI II - Seedling Vigor Index; DW - Dry Weight of seedling; GP - Germination

Percentage.

RESULTS AND DISCUSSION

The highest germination percentage was recorded in the 75 ppm GA3 treated seeds in
water abundant environment while this highest GP abated significantly by 16% in the case of
PEG stressed environment which coordinates with the conclusion exhibited by Afzal et al.
(2008) and Bhatt et al. (2022). Hydropriming has also been efficacious in escalating the
germination percentage giving the second highest GP. Similar trend was also reported by
Lara-viveros et al. (2018). In stressed environments, the GP of all eight treatments was
significantly diminished which complements with the outcomes obtained by Gnawali &
Subedi (2021). The least germination was documented in the 15% PEG solution treated
seeds in the stressed environment. GA3 treatments have revealed positive response for
germination percentage in both water-abundant and stressed environments. GA3 being a
natural regulator stimulates the production of A- amylase: a hydrolytic enzyme that helps in
germination (Gupta & Chakrabarty, 2013). In addition to this, catabolism activities of GA3 also
play the vital role in the metabolic pathways of germination inhibitors like ABA. In addition to
this, GA3 also acts as an antioxidant and reduces lipid peroxidation thus helping in enhancing
germination (Marthandan et al., 2020). PEG has been observed to ameliorate the
germination performance in the case of stressed conditions. This is due to the osmotic
adjustment by accumulating the osmolytes; decreasing the osmotic potential in response to
stress (Saha et al., 2022).
Mean Germination Time in the stressed condition is found to be longer than the water
abundant conditions irrespective of the treatments used. Similar results were also reported

115
 RJOAS, 9(129), September 2022

by Khodarahmpour (2011). GA3 100 ppm treated maize seeds required the least time for
germination.

Figure 1 – Germination Percentage (GP)

Although all priming treatments required a lower mean germination time compared to
control, maize seeds treated with all three gibberellic acid concentrations and 10% PEG
treated seeds have significantly lower mean germination time. These results have similarities
with the results obtained from Tian et al. (2014). There is also a significant difference in
mean germination time when only environments are considered. With the increasing
concentration of PEG treatments, germination time required also soared while there is an
exactly opposite trend in the case of gibberellic acid. These results complements with the
consequences obtained by Tian et al. (2014) and Gnawali & Subedi (2021). Slanting graphs
are observed in 15% PEG and 75 ppm GA3 as observed in the facet wrap graph shown
below. With the increasing GA3 concentration, cytological enzymes have been activated
which resulted in higher cell plasticity with rapid water absorption that caused quicker
germination (Chauhan et al., 2019), and with the decreasing PEG concentration, the time
required for seeds to germinate increased as a higher concentration of PEG have negative
effects in germination (Yuan et al., 2010). So, for prompt germination, a higher concentration
of GA3, lower concentration of PEG, or hydropriming can be recommended while the best
results can be obtained from priming by GA3 100 ppm solution.

Figure 2 – Mean Germination Time (MGT)

116
 RJOAS, 9(129), September 2022

The root-shoot ratio is remarkably impacted by both the seed priming treatments and
the environments used in the experiment. A balanced root-shoot ratio was found in water
abundant environment while a 1.51 R-S ratio was observed in the 10% PEG-induced stress
environment. This result is obtained because, in the induced environment, root length
increased significantly in search of water which directly influenced the R-S ratio. Similar
results were also demonstrated by Magar et al. (2019) and Queiroz et al. (2019). The highest
R-S ratio was noted in the maize seeds pre-treated with 50 ppm GA3 which significantly
decreased in the other two higher concentrations viz. 75 ppm and 100 ppm. As previously
discovered, gibberellic acid enhances leaf expansion but impedes root growth (Stowe &
Yamaki, 1957) although low GA3 concentration is essential for root elongation as per
Tanimoto (2012) and higher GA concentrations are inhibitory for root growth (Hedden &
Sponsel, 2015). These studies have exactly matched with our experiment's results. There
was no significant difference in the results of the R-S ratio observed in the different
concentrations of PEG as treatments. Similarly, hydropriming and control seeds also showed
a similar R-S ratio.

Figure 3 – Root-shoot ratio (R-S ratio)

Seedling Vigor Index II is not significantly affected by the priming agents and
environments. The highest SVI II was found to be in the maize seeds pre-treated with 75
ppm GA3. Similar results were also obtained in the other two concentrations (50 ppm and
100 ppm) of gibberellic acid which matches with the results exhibited by Chauhan et al.
(2019). Increasing the PEG concentration of priming treatments decreased the SVI II
(Khodarahmpour, 2011) while hydropriming caused to increase in SVI II. Similar trends were
also followed by the experiments conducted by Khodarahmpour (2011), ur Rehman et al.
(2015), and Marthandan et al. (2020).

117
 RJOAS, 9(129), September 2022

Figure 4 – Seedling Vigor Index II (SVI II)

Table 1 – Interaction effect of priming agents and environment on GP, MGT, RS ratio and
SVI II of Arun-4 maize seeds
Gemination Percentage Mean Germination time (MGT) Root shoot ratio (RS Seedling vigor index II
Treatment
(GP)(%) (Days) ratio) (SVI II)
Priming agent
Control 73.20 ab 4.97 a 1.37 a 312.80 ab
Hydro priming 76.45 a 4.89 ab 1.36 a 339.13 a
PEG (10%) 75.83 ab 4.77 bcd 1.25 ab 326.71 ab
PEG(15%) 61.67 bc 4.86 abc 1.27 ab 302.68 ab
PEG(20%) 58.38 c 4.91 a 1.27 ab 263.76 b
GA3 (50 ppm) 75.83 ab 4.75 cd 1.40 a 360.23 a
GA3 (75 ppm) 83.33 a 4.77 bcd 0.98 c 368.78 a
GA3 (100 ppm) 82.50 a 4.67 d 1.19 b 361.48 a
LSD0.05 14.46 0.13 0.17 71.96
p- value * 0.05 **0.05 ***0.05 . 0.05
Environment
Water 76.71 4.72 b 1.00 b 323.08 a
PEG (10%) 70.08 4.92 a 1.51 a 335.81 a
LSD0.05 7.23 0.06 0.08 35.98
p-value . 0.05 *** 0.05 ***0.05 - 0.05
CV% 16.75 2.33 11.64 18.57
Grand mean 73.39 4.82 1.26 329.44

Gibberellic acid increases metabolic plasticity which is the principal cellular mechanism
responsible for inducing growth. Polyethylene glycol induces electrolyte leaching due to
increased membrane plasticity that decreases the seed vigor. Thus, GA3 is recommended for
increasing seedling vigor. In addition to this, hydropriming can also be an effective economic
method for increasing seedling vigor.

CONCLUSION

Gibberellic acid priming with 75 ppm provided the best results in the early development
of maize among all the treatments. Increasing GA3 concentration while priming also gave
better results compared to control. In contrast to this, rising the concentration of polyethylene
glycol reduced the germination parameters. Thus, 5% PEG is the best pre-treating agent
when different levels of PEG are to be considered. For the consideration of the
environments, a PEG-induced stress environment resulted in a worsening of the germination
parameters. As indicated by the results of the experiment, the PEG-induced stress
environment negatively affected the germination percentage, mean germination time, and
seedling vigor index II. Application of GA3 priming in stressed environments exhibited better
germination performance than non-primed seeds. Thus, water abundant environment is the
best condition for enhancing germination; however in water stressed environment GA3
priming is the best priming reagent that provides better germination performance even in
water scarce conditions. Hydropriming also gave better results almost similar to that of GA3
priming. Thus, hydropriming practiced by farmers for better germination should be continued
and if available and affordable, GA3 priming should be practiced.

118
 RJOAS, 9(129), September 2022

REFERENCES

1. Abdul‐Baki, A.A. & Anderson, J.D. (1973) Vigor determination in soybean seed by
multiple criteria. Crop Science. [Online] 13 (6), 630–633.
2. Afzal, I., Basra, S. M. A., Shahid, M., & Farooq, M. (2008). Priming enhances germination
of spring maize (Zea mays L.) under cool conditions. January 2014.
https://doi.org/10.15258/sst.2008.36.2.26.
3. Ahammad, K., Rahman, M., & Ali, M. (2014). Effect of hydropriming method on maize
(Zea mays) seedling emergence. Bangladesh Journal of Agricultural Research, 39(1),
143–150. https://doi.org/10.3329/bjar.v39i1.20164.
4. Anupama, N., Murali, M., Jogaiah, S., & Amruthesh, K. N. (2014). Crude Oligossacarides
from Alternaria solani with Bacillus subtilis Enhance Defense Activity and Induce
Resistance Against Early Blight Disease of Tomato. Asian Journal of Science and
Technology, 5(7), 412–416.
5. Bhatt, A., Daibes, L. F., Gallacher, D. J., Jarma-orozco, A., & Pompelli, M. F. (2022).
Water Stress Inhibits Germination While Maintaining Embryo Viability of Subtropical
Wetland Seeds : A Functional Approach With Phylogenetic Contrasts. 13(May).
https://doi.org/10.3389/fpls.2022.906771.
6. Carvalho, R. F., Piotto, F. A., Schmidt, D., Peters, L. P., Monteiro, C. C., Azevedo, R. A.,
& Medici, L. O. (n.d.). Seed priming with hormones does not alleviate induced oxidative
stress in maize seedlings subjected to salt stress. In Sci. Agric (Issue 5).
7. Chauhan, A., AbuAmarah, B. A., Kumar, A., Verma, J. S., Ghramh, H. A., Khan, K. A., &
Ansari, M. J. (2019). Influence of gibberellic acid and different salt concentrations on
germination percentage and physiological parameters of oat cultivars. Saudi Journal of
Biological Sciences, 26(6), 1298–1304. https://doi.org/10.1016/j.sjbs.2019.04.014.
8. Cornea-Cipcigan, M., Pamfil, D., Sisea, C. R., & Mărgăoan, R. (2020). Gibberellic acid
can improve seed germination and ornamental quality of selected cyclamen species
grown under short and long days. Agronomy, 10(4).
https://doi.org/10.3390/agronomy10040516.
9. El-Sanatawy, A. M., El-Kholy, A. S. M., Ali, M. M. A., Awad, M. F., & Mansour, E. (2021).
Maize seedling establishment, grain yield and crop water productivity response to seed
priming and irrigation management in a mediterranean arid environment. Agronomy,
11(4). https://doi.org/10.3390/agronomy11040756.
10. Ghassemi-Golezani, K., Hosseinzadeh-Mahootchy, A., Zehtab-Salmasi, S., & Tourchi, M.
(n.d.). Improving Field Performance Of Aged Chickpea Seeds By Hydro-Priming Under
Water Stress. www.ijpaes.com.
11. Gnawali, A., & Subedi, R. (2021). Gibberellic Acid Priming Enhances Maize Seed
Germination Under Low Water Potential Priming Asam Giberelat Meningkatkan
Perkecambahan Benih Jagung pada Tekanan Potensial Air Rendah. Indonesian Journal
of Agricultural Science, 22(1), 17–26. https://doi.org/10.21082/ijas.v.22.n1.2021.p.17-26
12. Gupta, R., & Chakrabarty, S. K. (2013). Gibberellic acid in plant Still a mystery
unresolved. September, 1–5.
13. Hedden, P., & Sponsel, V. (2015). A Century of Gibberellin Research. Journal of Plant
Growth Regulation, 34(4), 740–760. https://doi.org/10.1007/s00344-015-9546-1.
14. Karki, T. B., Shrestha, J., & Achhami, B. B. (2015). Status and prospects of maize
research in Nepal. Journal of Maize Research and Development, 1(1), 1–9.
https://doi.org/10.5281/zenodo.34284.
15. Khodarahmpour, Z. (2011). Effect of drought stress induced by polyethylene glycol ( PEG
) on germination indices in corn ( Zea mays L.) hybrids. 10(79), 18222–18227.
https://doi.org/10.5897/AJB11.2639.
16. Lara-viveros, F. M., Landero-valenzuela, N., Javier, G., Bautista-rodríguez, E. I.,
Martínez-acosta, E., & Viveros, L. (2018). Effects of hydropriming on maize seeds ( Zea
mays L ) on growth , development , and yield of crops. 72–86.
17. Laware, S. L., Pawar, V. A., & Laware, S. L. (2018). Seed Priming A Critical Review Seed
Priming: A Critical Review. International Journal of Scientific Research in Review Paper.
Biological Sciences, 5(5), 94–101. https://doi.org/10.26438/ijsrbs/v5i5.94101.
18. Ma, H. Y., Zhao, D. D., Ning, Q. R., Wei, J. P., Li, Y., Wang, M. M., Liu, X. L., Jiang, C. J.,
& Liang, Z. W. (2018). A Multi-year Beneficial Effect of Seed Priming with Gibberellic

119
 RJOAS, 9(129), September 2022

Acid-3 (GA3) on Plant Growth and Production in a Perennial Grass, Leymus chinensis.
Scientific Reports, 8(1). https://doi.org/10.1038/s41598-018-31471-w.
19. Magar, M. M., Parajuli, A., Sah, B. P., Shrestha, J., Sakh, B. M., & Koirala, K. B. (2019).
Effect of PEG Induced Drought Stress on Germination and Seedling Traits of Maize ( Zea
mays L.) Lines. 6(2), 196–205.
20. Marthandan, V., Geetha, R., & Kumutha, K. (2020). Seed Priming : A Feasible Strategy to
Enhance Drought Tolerance in Crop Plants. Int. Journal of Molecular Sciences, 21, 1–23.
21. Mirmazloum, I., Kiss, A., Erdélyi, É., Ladányi, M., Németh, É. Z., & Radácsi, P. (2020).
The effect of osmopriming on seed germination and early seedling characteristics of
carum carvi L. Agriculture (Switzerland), 10(4).
https://doi.org/10.3390/agriculture10040094.
22. Queiroz, M. S., Oliveira, C. E. S., Steiner, F., Zuffo, A. M., Zoz, T., Vendruscolo, E. P.,
Silva, M. V, Mello, B. F. F. R., Cabral, R. C., & Menis, F. T. (2019). Drought Stresses on
Seed Germination and Early Growth of Maize and Sorghum. 11(2), 310–318.
https://doi.org/10.5539/jas.v11n2p310.
23. Saha, D., Choyal, P., Nandan, U., Dey, P., Bose, B., Kumar, N., Kumar, B., Kumar, P.,
Pandey, S., Chauhan, J., & Kumar, R. (2022). Plant Stress in plants. Plant Stress,
4(February), 100066. https://doi.org/10.1016/j.stress.2022.100066.
24. Salah, S. M., Yajing, G., Dongdong, C., Jie, L., Aamir, N., Qijuan, H., Weimin, H., Mingyu,
N., & Jin, H. (2015). Seed priming with polyethylene glycol regulating the physiological
and molecular mechanism in rice (Oryza sativa L.) under nano-ZnO stress. Scientific
Reports, 5(August), 1–14. https://doi.org/10.1038/srep14278.
25. Scott, S. J., Jones, R. A., & Williams, W. A. (1984). Review of Data Analysis Methods for
Seed Germination 1. Crop Science, 24(6), 1192–1199.
https://doi.org/10.2135/cropsci1984.0011183x002400060043x.
26. Shahzad, K., Hussain, S., Arfan, M., Hussain, S., Waraich, E. A., Zamir, S., Saddique,
M., Rauf, A., Kamal, K. Y., Hano, C., & El-Esawi, M. A. (2021). Exogenously applied
gibberellic acid enhances growth and salinity stress tolerance of maize through
modulating the morpho-physiological, biochemical and molecular attributes.
Biomolecules, 11(7), 1–17. https://doi.org/10.3390/biom11071005.
27. Shrestha, J., Kandel, M., & Chaudhary, A. (2018). Effects of planting time on growth,
development and productivity of maize (Zea mays L.). Journal of Agriculture and Natural
Resources, 1(1), 43–50.
28. Stowe, B. B., & Yamaki, T. (1957). The history. Plant Physiology, 8, 181–216.
29. Subedi, R., Maharjan, B., & Adhikari, R. (2015). Effect of different priming methods in rice
(Oryza sativa). Journal of Agriculture and Environment, 16(June), 152–160.
https://doi.org/10.3126/aej.v16i0.19848.
30. Tanimoto, E. (2012). Tall or short ? Slender or thick ? A plant strategy for regulating
elongation growth of roots by low concentrations of gibberellin. 373–381.
https://doi.org/10.1093/aob/mcs049.
31. Tian, Y., Guan, B., Zhou, D., Yu, J., Li, G., & Lou, Y. (2014). Responses of seed
germination, seedling growth, and seed yield traits to seed pretreatment in maize (Zea
mays L.). Scientific World Journal, 2014. https://doi.org/10.1155/2014/834630.
32. Ur Rehman, H., Basra, S. M. A., & Farooq, M. (2011). Field appraisal of seed priming to
improve the growth, yield, and quality of direct seeded rice. Turkish Journal of Agriculture
and Forestry, 35(4), 357–367. https://doi.org/10.3906/tar-1004-954.
33. ur Rehman, H., Iqbal, H., Basra, S. M. A., Afzal, I., Farooq, M., Wakeel, A., & Wang, N.
(2015). Seed priming improves early seedling vigor, growth and productivity of spring
maize. Journal of Integrative Agriculture, 14(9), 1745–1754.
https://doi.org/10.1016/S2095-3119(14)61000-5.
34. Wolny, E., Betekhtin, A., Rojek, M., Braszewska-Zalewska, A., Lusinska, J., & Hasterok,
R. (2018). Germination and the early stages of seedling development in brachypodium
distachyon. International Journal of Molecular Sciences, 19(10).
https://doi.org/10.3390/ijms19102916.
35. Zhang, F., Yu, J., Johnston, C. R., Wang, Y., Zhu, K., Lu, F., Zhang, Z., & Zou, J. (2015).
Seed priming with polyethylene glycol induces physiological changes in sorghum
(Sorghum bicolor L. moench) seedlings under suboptimal soil moisture environments.
PLoS ONE, 10(10). https://doi.org/10.1371/journal.pone.0140620.

120