Throughout the development of fertilizers in the past ten years, seaweed fertilizers are still attracting attention, but there are not many introductions about how seaweed fertilizers work. So, what exactly is a scientific, efficient and stable seaweed fertilizer?
Seaweed fertilizer refers to a product made from macroalgae (kelp, sargassum, Ascophyllum nodosum, etc.) that grow in the ocean through chemical, physical, biological, and enzymatic processes. By stimulating the synthesis of endogenous hormones in crops, it can promote plant growth, increase yield, and improve the quality of agricultural products.
So which core ingredient in seaweed fertilizer is at work?
1. The essence of seaweed extraction: fucoidan oligosaccharides
Let’s first try to discuss the often mentioned seaweed extract. Three elements of seaweed essence:
- Not mixed with other chemical substances;
- Does not destroy the essence of seaweed,
- Release the essence of seaweed to the greatest extent.
2. Can the very small amount of hormones in the seaweed extract play a role?
The seaweed extract prepared by simple physical, chemical, biological and other methods, after collation of the data of many documents, shows that the above-mentioned essential ingredients – fucoidan oligosaccharides, cannot be released. And the seaweed extract only contains seaweed macromolecular substances such as polysaccharides and alginic acid. Even if they contain hormones such as zeatin, indole acetic acid, and abscisic acid, the content is only in μg/g units. Can they exert their effect? When it is added to the fertilizer, it has been diluted hundreds of times, and the fertilizer will be diluted hundreds of times in the terminal use. So it is equivalent to tens of thousands of times of dilution, and the content is negligible.
3. The relationship between seaweed extract, alginic acid, alginate, and highly active fucoidan oligosaccharides.
When it comes to seaweed fertilizer, terms such as seaweed extract, alginic acid, alginate, and fucoidan oligosaccharides usually come to mind, but there are huge differences in prices. The reason is that these substances are related but not equal, and there is a huge difference in value.
The active substance content in the seaweed extract is low, and the small molecular active substance cannot be released. Alginate and alginic acid, one is that alginic acid and alginate are insoluble substances. The second is that the molecular weight is large, and it is usually colloidal in shape after dissolve in water, which is difficult for plants to absorb.
Fucoidan oligosaccharides are sugars that crack macromolecules of alginic acid and alginate into small molecules, which are beneficial for plants to absorb and utilize. Studies have shown that molecular weight <1000 is more active.
4. How does the essence of seaweed fertilizer (highly active fucoidan oligosaccharide) work?
Highly active fucoidan oligosaccharides play a key role in plant growth promotion, and can stimulate and induce the synthesis of plant endogenous hormones.
Plant endogenous hormones are signaling compounds that regulate key aspects of plant growth, development, and environmental stress responses. For example:
IAA (auuxin): promotes seed germination, ovary development, and promotes rooting;
ABA (abscisic acid): promotes dormancy, causes stomata to close, improves crop and stress resistance, and promotes fruit coloring;
GA (gibberellin): Promotes cell elongation, stimulates leaf and bud growth.
Studies have shown that the treatment of fucoidan oligosaccharides can significantly increase the content of indole acetic acid (IAA) and gibberellin (GA). When the concentration of fucoidan oligosaccharides is 0.15%, the effect is the best, and the growth of roots and shoots of seaweed fertilizer is significantly improved.
