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Explora: Environment
and Resource Application of Algae for seed priming

Figure 5. Modulation of algal phytohormones in seedling growth
Abbreviations: ABA: Abscisic acid; GA: Gibberellin.

stress and promoting healthy seedling development. 3,121 integrity. Algal extracts from U. lactuca and K. alvarezii
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Integrating algal priming into agricultural practices, can are rich in polyphenolic compounds that scavenge free
significantly improve seed viability and germination radicals, reducing oxidative damage during germinating.
efficiency, particularly under stress-prone environments Carotenoids, abundantly found in D. salina and H. pluvialis,
(Figure 6). During early germination, ROS, such as act as potent ROS quenchers, stabilizing membrane
superoxide radicals, hydrogen peroxide, and hydroxyl structures and ensuring efficient energy metabolism
radicals are naturally generated as metabolic activity during early seedling establishment. 126,127 Furthermore,
increases. While controlled ROS levels act as signaling algal polysaccharides, such as fucoidans, laminarins, and
molecules for seed dormancy release and metabolic alginates help mitigate oxidative stress by acting as signaling
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activation, excessive accumulation leads to oxidative stress, molecules that induce stress-responsive pathways. Marine
causing lipid peroxidation, protein oxidation, and DNA algae, such as Laminaria, Kappaphycus, Sargassum, Ulva,
damage. and Fucus are particularly rich in these polysaccharides,
which enhance the synthesis of stress-protective proteins
Algal extracts, rich in natural antioxidants, help regulate
this balance by enhancing both enzymatic and non- and antioxidants in germinating seeds. These compounds
not only improve germination percentage and speed but
enzymatic antioxidant systems within seeds. Enzymatic also increase the resilience of emerging seedlings under
antioxidants, including SOD, CAT, and peroxidases, play adverse environmental conditions. 4,96
a vital role in scavenging ROS and preventing cellular
damage. 3,122 Several studies have demonstrated that 4.4. Boosting nutrient bioavailability
priming seeds with algal extracts enhances the activity of Algal priming significantly boosts nutrient bioavailability
these enzymes, leading to improved germination rates during seed germination, ensuring essential macro- and
and seedling vigor. Microalgae, such as S. platensis and micronutrients are readily available for early seedling
C. vulgaris contain high levels of antioxidant enzymes development. This increased nutrient availability provides
and stimulate endogenous defense mechanisms in primed a significant advantage, particularly in nutrient-deficient
seeds, enabling them to withstand oxidative stress during or stress-prone environments. Algal extracts supply
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germination. 123,124 Similarly, brown seaweeds, such as chelated minerals, bioavailable nitrogen and phosphorus,
A. nodosum and S. wightii provide bioactive compounds that and bioactive compounds that stimulate nutrient uptake
upregulate the expression of genes related to antioxidant and metabolism, acting as natural growth enhancers to
enzyme synthesis, ensuring a robust defense response. 77
support robust seedling establishment and long-term
In addition to enzymatic antioxidants, non-enzymatic plant health (Figure 7). Seeds require a precise balance
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antioxidants, such as polyphenols, flavonoids, carotenoids, of nutrients – such as nitrogen, phosphorus, potassium,
and vitamins (e.g., vitamin C and vitamin E) play a iron, calcium, magnesium, and trace elements, such as
crucial role in neutralizing ROS and protecting cellular zinc, manganese, and selenium – to support metabolic

Volume 2 Issue 2 (2025) 13 doi: 10.36922/EER025120025