3. Introduction
Seed priming is a pre-sowing treatment that enables
seeds to germinate more efficiently.
It is the method of improving germination and uniform
emergence of seedlings in field conditions.
It involves the imbibition of seeds under controlled
conditions, followed by drying the seed back to its
initial moisture content.
4. History
Ancient Greeks experimented with lettuce and cress seeds
in seawater.
Theophrastus(371-287 B.C.) observed soaked cucumber
seeds resulted in faster and uniform germination as
compared to the unprimed seeds.
The term seed priming was coined by Heydecker in 1973.
7. Benefits of seed priming
•Faster emergence
•Improves seed performance under stress conditions
•Improves uniformity to optimize harvesting efficiency
•Increases vigor for fast and strong plant development
•Increases the yield potential
•Increases the germination percentage of crop
•Crops can compete more effectively with weeds
•Protects the seed from soil-borne pathogens
8. Methods of
Priming
Conventional methods
• Hydro priming
• Halo priming
• Osmo-priming
• Solid matrix priming
• Hormonal priming
• Bio priming
Advanced methods
•Priming through
nanoparticles
•Priming through physical
agents
9. Hydro priming
Soaking of seeds in water before sowing is known as hydro
priming.
Water is used as priming agent.
Hydro priming enhances seed germination percentage and
seedling emergence.
Plant can perform better under drought condition.
10. Halo priming
Seeds are soaked in solution of inorganic salts like
NaCl, KNO3, CaCl2, CaSO4, etc.
Results in improvement in seed germination, seedling
emergence and establishment and final crop yield in
salt affected soil.
11. Osmo-priming
It is a technique where seeds are soaked in sugar solution for a
certain period followed by air drying of seeds before sowing.
PEG(Polyethylene Glycol), sugar, mannitol are widely used osmo-
priming agent.
Priming affected the plant height, grain rows and 1000-grain
weight, grain and biological yield, and harvest index. (Rehman et
al., 2015).
12. Solid Matrix Priming
Solid matrix priming is the process of combining seed in a
precise ratio with water and solid substance.
Peat moss, vermiculite, charcoal, clay, and sand are the
most often employed solid carriers.
13. Hormonal priming
In this method seeds are treated with different plant growth
hormones like GA3, kinetin, NAA and ascorbate etc.
Commonly utilized substances include regulators such
salicylic acid, abscisic acid, and ascorbic acid, cytokinins,
auxins, gibberellins, kinetin, ethylene, and polyamines(Tania
& Khatun, 2020).
14. Hydration of
Seeds
Bio priming
In this method seeds are inoculated with microbial
inoculation.
The microbes used for bio-priming belong to Pseudomonas
spp., Enterobacter spp., Trichoderma spp., and Bacillus spp.
It not only promotes the germination and seedling
emergence of crop but also protects the seed against the
soil borne pathogens.
+ Bio Agents
Bio-priming of
seeds
=
15. Advanced Method of Seed
Priming
Seed priming through Nanoparticles
This technology utilizes nanoparticles less than 100nm in size.
Different nanomaterials like metallic, biogenic metallic, and
polymeric nanoparticles are used for seed nano priming.
Seed priming through physical agents
Magnetic field, UV radiation, gamma radiation, X-rays and
microwaves are some of the physical agents used for priming
16. Crop Priming method Observation Reference
Rice Hydro priming Higher germnation rate
Higher enzymatic activities
Longer radicle and plumule
(Lemmens et al.,
2019)
Sorghum Hydro priming Increase in plant weight, root
length, roots number, shoot
length, vigor index and time
taken to 50% percent
emergence
(Adnan, Abd-ur-
Rahman, et al.,
2020)
Rice Halo
priming[KNO3
and Mg(NO3)2]
Improve plant height, leaf
number, leaf area, viable
tillers, grain yield, and panicle
quality
(Srivastava & Bose,
2012)
Maize Halo
priming(KNO3)
enhanced biological yield,
weight of tassel, harvest
index, germination, faster
emergence, and inhibition of
abiotic and biotic factors
(Vazirimehr et al.,
2014)
Impact of Priming on
Germination
17. Crop Priming methods Observation References
Wheat Osmo priming Improve grain yield, and
economic yield under
drought as well as
irrigated conditions,
compensated the
drought-induced losses
(Farooq et al.,
2017)
Soybean Solid matrix
priming
Increase in seed vigor
and faster germination
(Adnan, Abd-Ur-
Rahman, et al.,
2020)
Maize Solid matrix
priming
A-amylase activity, and
emergence speed
boosted
(Adnan, Abd-Ur-
Rahman, et al.,
2020)
Wheat Hormonal
priming(GA3)
improved salt tolerance
with respect to growth
and grain yield
(Tania & Khatun,
2020)
18. Crop Priming methods Observation Reference
Bio priming improve overall plant
growth and development
altering the physiological,
biochemical and molecular
mechanism
(Sukanya, 2018)
Wheat Nano particlces(zinc
and iron oxides)
increasing spike length,
plant biomass, chlorophyll
contents, and
photosynthetic parameters
(Rizwan et al,
2019)
Sorghum Nano particles(iron
oxide)
Enhanced seed
germination and plant
growth
(Maswada, 2018)
19. Conclusion
Easy and economical method to enhance germination and
crop stand in the field.
Various priming techniques used worldwide for increasing
the germination percentage, vigor, and other physiological,
morphological, and metabolic traits.
Climatic change has affected the crop environment so as to
combat the severity priming techniques can be appropriate
one.
