Seaweed extract fertilizer is a type of fertilizer produced from marine brown algae. It is often further processed with a certain amount of nitrogen, phosphorus, potassium, and trace elements. The product comes in various forms, with liquid and powder being the most common on the market, and granules being relatively rare.
Main Active Substances
Marine brown algae contain a variety of substances. The main active substances that have been studied in seaweed and seaweed plant growth regulators include the following:
Cytokinins
Cytokinins belong to the class of cell division factors and are physiologically active purine derivatives. Research shows that brown algae and red algae like Gracilaria mainly contain cytokinins such as t-zeatin, dihydrozeatin, isopentenyladenine, and t-zeatin riboside.
Auxins
Existing research indicates that auxins stimulate the development of crop root systems and have a frost-resistant effect. Treating plants with it during cutting can significantly improve the survival rate.
Gibberellins
Gibberellins promote plant germination, growth, flowering, and fruiting.
Abscisic Acid (ABA)
Also known as abscission acid, ABA is a plant growth inhibitor that promotes the maturation of abscission cells, leading to organ shedding. Abscisic acid has an antagonistic effect with gibberellins.
Ethylene
The role of ethylene in plant growth is to reduce growth speed and promote early fruit ripening.
Betaine
Betaine is a derivative of amino acids or sub-amino acids. At very low concentrations, it can significantly increase the chlorophyll content in plants.
Polyamines
Polyamines are a group of compounds similar in action to plant auxins but are not classified as plant hormones. Polyamines can broadly affect the physiological growth processes of plants.
Mechanism of Action
Seaweed is the primary producer of marine organic matter and has a strong adsorption capacity. It can concentrate marine substances up to 440,000 times its own mass, making it extremely rich and balanced in nutrients.”
Composition of Seaweed Fertilizer
Organic Seaweed fertilizer is a bio-fertilizer made from marine plants, primarily seaweed, through scientific processing. Its main components are natural bioactive substances extracted from seaweed that are beneficial for plant growth and development, as well as mineral nutrients that seaweed absorbs and accumulates from the ocean. These include:
- Seaweed Polysaccharides: Complex carbohydrates beneficial for plant growth.
- Phenolic Polymers: Organic compounds that have various beneficial effects on plants.
- Mannitol: A type of sugar alcohol that serves as an osmoprotectant.
- Betaine: An amino acid derivative that enhances chlorophyll content in plants.
- Plant Growth Regulators: Such as cytokinins, gibberellins, auxins, and abscisic acid.
- Micro and Macro Nutrients: Including nitrogen, phosphorus, potassium, as well as trace elements like iron, boron, molybdenum, and iodine.
In addition, to enhance the fertilizer’s efficacy and chelating action, a suitable amount of humic acid and trace elements are also dissolved in it.
Foliar fertilization, also known as non-root fertilization, involves supplementing plants with essential nutrients by spraying them onto the leaf surface. This method helps regulate plant growth, replenish missing elements, prevent early aging, and increase yield. Seaweed fertilizer is a branch of foliar fertilizers.
Application Techniques
Foliar Fertilization: Also known as non-root fertilization, this method involves supplementing plants with essential nutrients by spraying them onto the leaf surface. It helps regulate plant growth, replenish missing elements, prevent early aging, and increase yield. Seaweed fertilizer is a branch of foliar fertilizers.
It’s crucial to emphasize two points:
- Field Experiment Results: A significant amount of field experiment results have shown that plants under growth stress factors (nutrition, climate, moisture) tend to exhibit more pronounced effects from foliar fertilization.
- Root Fertilization: Root fertilization is the fundamental fertilization method, while non-root fertilization is supplementary. It’s essential not to invert the importance of the two.