Discover the most important examples of unicellular algae in agriculture: Chlorella, Scenedesmus, Spirulina. Benefits, applications, and costs. Complete guide.
Unicellular algae are photosynthetic microorganisms that include species such as Chlorella vulgaris, Scenedesmus obliquus, Spirulina platensis, and Dunaliella salina. These aquatic organisms are key examples of unicellular algae used in agriculture as biostimulants, fertilizers, and bioprotectants. Their controlled cultivation yields biomass rich in phytohormones, amino acids, vitamins, and minerals that enhance plant growth, abiotic stress tolerance, and crop quality. By 2026, their use has expanded in Latin America for crops such as coffee, avocado, citrus, and maize, offering a sustainable alternative to synthetic inputs.
What are unicellular algae and what are their main examples?
Unicellular algae, also known as microalgae, are eukaryotic or prokaryotic organisms (cyanobacteria) that perform photosynthesis and live in aquatic environments. They are characterized by their high growth rate and ability to accumulate bioactive compounds. The most relevant examples for agriculture include:
- Chlorella vulgaris: a unicellular green alga rich in proteins, B vitamins, iron, and nucleic acids. It stimulates cell division and rooting. It is used in vegetable and fruit crops.
- Scenedesmus obliquus: colonial green alga that produces polysaccharides and plant hormones such as auxins and cytokinins. It improves photosynthesis and nutrient uptake. Applied in corn, soybeans, and coffee.
- Spirulina platensis: unicellular cyanobacterium (though it forms filaments) with high content of phycocyanin, antioxidants, and essential fatty acids. It strengthens plants' immune system against pathogens.
- Dunaliella salina: halophilic alga that produces beta-carotene and glycerol. Useful under saline stress conditions, improving crop tolerance in saline soils.
- Haematococcus pluvialis: green alga that accumulates astaxanthin, a potent antioxidant. It is being researched to protect crops from oxidative stress caused by UV radiation.
Agricultural applications of unicellular algae
Microalgae are applied in agriculture as foliar or root biostimulants. For example, Chlorella vulgaris is used at doses of 2-5 L/ha in tomatoes to improve fruit set and increase soluble solids content. Scenedesmus obliquus has been tested in corn at a rate of 3 L/ha at the V6 stage, achieving yield increases of up to 15% in field trials. Spirulina platensis is applied in citrus to reduce the incidence of fungi such as Phytophthora, thanks to its elicitor effect. Dunaliella salina is recommended in saline soils for avocado and strawberry, improving stomatal conductance and net photosynthesis.
The most common application method is foliar, during critical phenological stages: flowering, fruit set, and fruit filling. They are also used in fertigation at doses of 1-2 L/ha, combined with fulvic acids to improve micronutrient chelation. Application frequency ranges from 2 to 4 applications per cycle, depending on the crop and stress conditions.
Prices and costs of commercial products
Prices of commercial products based on unicellular algae vary according to species, concentration, and presentation. Below is a table with estimated prices in USD for 2026 in Latin America:
| Algae Type | Presentation | Concentration | Price (USD/L or kg) | Region |
|---|---|---|---|---|
| Chlorella vulgaris | Liquid | 10^7 cells/mL | 15-25 | Mexico, Colombia |
| Scenedesmus obliquus | Liquid | 10^6 cells/mL | 12-20 | Brazil, Argentina |
| Spirulina platensis | Powder | 100% pure | 30-50 | Peru, Ecuador |
| Dunaliella salina | Liquid | 10^5 cells/mL | 18-30 | Chile, Mexico |
| Haematococcus pluvialis | Powder | 2% astaxanthin | 80-120 | Global |
These prices are for reference only and may vary depending on the supplier and purchase volume. Costs per hectare per application range from 30 to 80 USD, depending on the dosage and number of applications.
Documented Agronomic Benefits
Recent research has shown that unicellular algae improve seed germination, root development, and nutrient use efficiency. For example, in trials with Chlorella on tomatoes, a 20% increase in root biomass and greater nitrate reductase enzyme activity were observed. Scenedesmus has shown increases in chlorophyll concentration and photosynthetic rate in maize under water stress. Spirulina induces systemic resistance in citrus against black spot, reducing disease severity by 40% according to field studies.
Additionally, microalgae contribute to soil health by releasing exopolysaccharides that improve aggregation and water retention. They also promote beneficial microbial activity, such as nitrogen-fixing bacteria and mycorrhizal fungi. These effects result in more resilient and higher-quality crops.
Our Field Experience
At Ecoganic, we have worked with unicellular algae since 2018, developing formulations based on Scenedesmus and Chlorella for avocado crops in Michoacán (Mexico) and coffee in Huila (Colombia). In a 2023-2025 project on Hass avocado, applying Scenedesmus at 3 L/ha at three stages (flowering, fruit set, and filling) resulted in an average 18% increase in yield and improved fruit firmness. In coffee, combined application with fulvic acids reduced rust incidence by 30% on farms in the Sierra Nevada de Santa Marta.
We have observed that effectiveness depends on the quality of the application water (pH between 6 and 7, low hardness) and integration with other management practices such as balanced fertilization and biological control. Our technicians train farmers to adjust dosages and timing according to the crop and climatic conditions.
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Frequently asked questions
What are the most common examples of unicellular algae in agriculture?
The most common examples are Chlorella vulgaris, Scenedesmus obliquus, Spirulina platensis, and Dunaliella salina. These microalgae are commercially cultivated and sold as liquid or powder biostimulants.
How much does a liter of unicellular algae biostimulant cost?
The price ranges from 12 to 30 USD per liter for liquid Chlorella or Scenedesmus products, depending on concentration and supplier. Spirulina powders can cost between 30 and 50 USD per kg.
On which crops is it recommended to apply unicellular algae?
They are recommended for high-value crops such as avocado, citrus, coffee, tomato, corn, and soybean. Also for greenhouse vegetables and fruit trees. They are especially useful under abiotic stress conditions (drought, salinity, high temperatures).
What is the typical dose per hectare?
The typical foliar dose is 2 to 5 L/ha, depending on the crop and formulation. For fertigation, 1-2 L/ha are used. 2 to 4 applications per cycle are recommended at key phenological stages.
Do unicellular algae replace chemical fertilizers?
They do not completely replace them, but they reduce the need for synthetic fertilizers by improving nutrient uptake efficiency. They act as biostimulants that complement conventional or organic nutrition.
Where to buy unicellular algae products in Latin America?
They can be purchased through specialized agricultural distributors or directly from manufacturers like Ecoganic, which offers certified formulations for organic farming. Request your free quote to learn about options.
How long does it take to see results?
The effects on plant growth are visible between 7 and 14 days after application. Improvements in yield and quality are observed at the end of the cycle, after 2-3 applications.
Are unicellular algae safe for the environment?
Yes, they are biodegradable and non-toxic. Their production has a low carbon footprint and generates no hazardous waste. They are permitted in organic agriculture under regulations such as EU 2018/848 and NOP USDA.
Related articles
- Organic agricultural biostimulants
- Certified organic fertilizers
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Frequently Asked Questions
What are the most common examples of unicellular algae in agriculture?
The most common examples are Chlorella vulgaris, Scenedesmus obliquus, Spirulina platensis, and Dunaliella salina. These microalgae are commercially cultivated and sold as liquid biostimulants or powders.
How much does a liter of unicellular algae biostimulant cost?
The price ranges from 12 to 30 USD per liter for liquid products of Chlorella or Scenedesmus, depending on concentration and supplier. Spirulina powders can cost between 30 and 50 USD per kg.
On which crops is it recommended to apply unicellular algae?
They are recommended for high-value crops such as avocado, citrus, coffee, tomato, corn, and soybeans. Also for greenhouse vegetables and fruit trees. They are especially useful under abiotic stress conditions.
What is the typical dosage per hectare?
The typical foliar dosage is 2 to 5 L/ha, depending on the crop and formulation. For fertigation, 1-2 L/ha are used. 2 to 4 applications per cycle are recommended at key phenological stages.
Do unicellular algae replace chemical fertilizers?
They do not completely replace them, but they reduce the need for synthetic fertilizers by improving nutrient uptake efficiency. They act as biostimulants that complement conventional or organic nutrition.
Where can I buy unicellular algae products in Latin America?
They can be purchased through specialized agricultural distributors or directly from manufacturers such as Ecoganic, which offers certified formulations for organic agriculture. Request your free quote to learn about options.
How long does it take to see results?
The effects on plant growth are visible between 7 and 14 days after application. Improvements in yield and quality are observed at the end of the cycle, after 2-3 applications.
Are unicellular algae safe for the environment?
Yes, they are biodegradable and non-toxic. Their production has a low carbon footprint and does not generate hazardous waste. They are permitted in organic farming under regulations such as EU 2018/848 and NOP USDA.
