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Explora: Environment
and Resource Application of Algae for seed priming

is crucial for enzyme activation, osmotic regulation, and algae, such as Grateloupia doryphore, Crassiphycus corneus,
metabolic processes, its efficient uptake ensures optimal U. fasciata, Nannochloropsis oculata, and Gracilaria cornea,
cellular function even in saline conditions. 139 not only preserve osmotic balance but also enhance seed
Phytohormones, particularly ABA from species, such vigor by promoting rapid metabolic activation during
as A. nodosum, help fine-tune germination under stress germination. 141
by inducing protective responses that delay germination 5. Influence of algal priming on the primary
until favorable conditions prevail. ABA-like compounds
also regulate seed dormancy release by allowing seeds metabolism of seedlings
to germinate only when water conditions are favorable. Algal priming plays a crucial role in modulating primary
This mechanism prevents pre-mature germination under metabolism during seed germination by enhancing
transient moisture conditions, reducing the risk of seedling carbohydrate, nitrogen, and lipid metabolic pathways
mortality. Algal priming also enhances the synthesis of (Figure 9). Among these, the hydrolysis of stored
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142
stress-related proteins and heat shock proteins, which carbohydrates is an important event in early seedling
play a key role in protecting cellular components from development, providing the energy required for cellular
damage caused by temperature fluctuations and osmotic processes. Algal-derived biomolecules regulate the
stress. These proteins prevent protein denaturation and expression of hydrolytic enzymes, such as α-amylase,
assist in proper protein folding, maintaining cellular β-amylase, and invertases, facilitating the breakdown of
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stability during germination. In addition, sulfated starch reserves into soluble sugars. These sugars, including
polysaccharides, such as fucoidans and carrageenans form glucose, fructose, and sucrose, serve as primary energy
brown and red algae, exhibit strong protective effects sources fueling glycolysis and the tricarboxylic acid (TCA)
against oxidative and osmotic stress by reinforcing cell cycle. 76,77,143 Extracts from A. nodosum and K. alvarezii
wall integrity and stabilizing membrane lipids. 83,115 Algal- have been reported to enhance amylase activity in primed
derived polyamines, such as putrescine, spermidine, seeds, leading to higher availability of soluble sugars and
and spermine, also contribute to stress tolerance by improved ATP production. This rapid mobilization of
modulating ion channels, stabilizing nucleic acids, and carbohydrate reserves accelerates radicle protrusion and
improving membrane fluidity. These molecules, found in seedling emergence. 144

Figure 9. Influence of algal priming on primary metabolism during seedling development
Abbreviation: TCA: Tricarboxylic acid.

Volume 2 Issue 2 (2025) 16 doi: 10.36922/EER025120025