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Explora: Environment
and Resource Application of Algae for seed priming

which are critical for DNA replication, protein synthesis, and oxidative stress. By supplying osmoprotectants,
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and ATP production during germination. Green algae, regulating ion transport, modulating stress-responsive
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such as C. vulgaris and S. platensis are known for their high gene expression, and activating protective proteins, algal
nitrogen content in the form of amino acids and peptides, extracts help seeds overcome abiotic challenges and ensure
serving as immediate nitrogen sources for metabolic successful germination (Figure 8). This makes algal-
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activation in germinating seeds. 123,124 Phosphorus, an based seed priming an effective and sustainable strategy for
essential component of nucleotides and energy-transfer improving germination rates and seedling establishment in
molecules, is also present in bioavailable forms in algal diverse environmental conditions. Germination is highly
extracts, ensuring optimal energy metabolism during sensitive to external stressors, and disruptions in water
the transition from seed dormancy to active growth. uptake, ion homeostasis, or cellular integrity can delay
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Moreover, bioactive compounds, such as polyphenols, or even inhibit seedling emergence. Algal extracts, rich
flavonoids, and amino acids in algal extracts not only in osmoprotectants and bioactive compounds, help seeds
improve nutrient uptake but also enhance enzymatic maintain cellular water balance, mitigate ionic toxicity, and
activity related to nutrient metabolism. For example, improve resilience to abiotic stressors. 2,135
3,4
seaweed-based priming has been shown to upregulate
genes involved in nutrient transport, particularly for One primary mechanism for regulating osmotic balance
nitrogen and phosphorus, ensuring that absorbed involves the high content of osmolytes – such as proline,
nutrients are efficiently utilized for metabolism, resulting betaine, and polyols – in algal extracts. These compounds
in faster and more uniform germination. Polysaccharides, function as osmoprotectants, stabilizing cellular
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such as fucoidans and laminarins, abundant in brown structures and preventing dehydration under water-deficit
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and red algae, such as F. vesiculosus and K. alvarezii, also conditions. For example, green algae, such as C. vulgaris
act as nutrient carriers and biostimulants. They facilitate and D. salina accumulate high levels of betaine and
nutrient transport across cell membranes and promote glycerol, which preserve intracellular osmotic pressure,
root hair formation, improving nutrient uptake efficiency. prevent water loss, and protect membrane integrity and
This ensures a steady nutrient supply during germination, enzymatic activity under osmotic stress. 136,137 In addition,
shortens the lag phase, and improves seedling vigor. 83,104 algal priming improves ion homeostasis by regulating
the uptake and distribution of essential and toxic ions
4.5. Regulating osmotic balance and enhancing during germination. Salinity stress often leads to excessive
stress tolerance accumulation of sodium and chloride ions, which disrupt
Algal priming plays a crucial role in regulating osmotic cellular function. Algal extracts derived from salt-tolerant
balance and enhancing stress tolerance during seed species, such as K. alvarezii, Gracilaria dura, and S. wightii
germination, enabling seeds to withstand unfavorable mitigate salt-induced stress by promoting potassium ion
environmental conditions, such as drought, salinity, retention and reducing sodium toxicity. Since potassium
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Figure 8. Effect of seed priming on osmotic balance and stress tolerance

Volume 2 Issue 2 (2025) 15 doi: 10.36922/EER025120025