What is Eriksson’s Medium and How is it Used in Tissue Culture?
Plant tissue culture offers tremendous prospects in agriculture, horticulture, and biotechnology, enabling researchers to propagate plants, conserve rare species, and produce genetically identical clones quickly. A key aspect of successful plant tissue culture is the use of appropriate culture media. One such medium that has gained popularity, especially in studies involving algae and some specific higher plants, is Eriksson’s Medium.
In this blog post, we will break down what Eriksson’s Medium is, its uses, and its formulation on a per-litre basis.
What is Eriksson’s Medium?
Eriksson’s Medium (sometimes abbreviated as ER) is a synthetic nutrient medium used in plant tissue culture systems. It was first developed by Torsten Eriksson in 1965, and it has been especially tailored for algal cultures but also supports the growth of vascular plants in vitro. The medium provides essential macronutrients and micronutrients that support cell growth, tissue regeneration, and organ formation.
Eriksson’s Medium distinguishes itself from other widely-used plant tissue culture media (like MS medium, developed by Murashige and Skoog) in its nutrient composition, especially in how it caters to different types of plant tissues’ specific needs.
What is Eriksson’s Medium Used For?
Eriksson’s Medium is primarily used for:
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Algal Studies: Eriksson’s Medium has often been used for the growth and study of algae. Algae play important roles in ecological systems and are being increasingly studied for biofuel production, bioremediation, and food source trials.
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Plant Tissue Culture: While not as commonly used for general plant tissue culture as MS medium, Eriksson’s Medium has been applied for certain specialized plant cultures. It provides a fine balance of nutrients that can work well for the in vitro culture of some mosses, ferns, and specific vascular plant tissues.
- Experimental Studies: Many researchers use Eriksson’s Medium for experimental purposes to study plant cell metabolism, growth, and differentiation, particularly to investigate the effect of micronutrients or trace elements at specific concentrations on plant regeneration.
Components of Eriksson’s Medium
Like other plant tissue culture media, Eriksson’s Medium supplies the necessary nutrients and sustenance for plant cells to thrive in an in vitro environment. It contains:
- Macronutrients like nitrogen, potassium, and phosphorus.
- Micronutrients, including essential trace elements like iron, zinc, and manganese.
- Vitamins, which help support cellular metabolism.
- Additionally, plant hormones or growth regulators can be added to the medium to promote specific outcomes like shoot or root formation, though they are not inherently part of the original composition.
Formulation of Eriksson’s Medium (per litre)
Below is the standard formulation of Eriksson’s Medium on a per-litre basis:
Macronutrients:
- NH₄NO₃ (Ammonium nitrate): 100 mg
- KNO₃ (Potassium nitrate): 800 mg
- CaCl₂·2H₂O (Calcium chloride dihydrate): 150 mg
- MgSO₄·7H₂O (Magnesium sulfate heptahydrate): 370 mg
- KH₂PO₄ (Potassium dihydrogen phosphate): 136 mg
Micronutrients:
- FeSO₄·7H₂O (Ferrous sulfate heptahydrate): 20 mg
- *Na₂EDTA2H₄O (Disodium EDTA):** 27 mg
- MnSO₄·4H₂O (Manganese sulfate tetrahydrate): 10 mg
- ZnSO₄·7H₂O (Zinc sulfate heptahydrate): 5.3 mg
- H₃BO₃ (Boric acid): 3 mg
- CuSO₄·5H₂O (Copper sulfate pentahydrate): 0.01 mg
- Na₂MoO₄·2H₂O (Sodium molybdate dihydrate): 0.025 mg
- CoCl₂·6H₂O (Cobalt chloride hexahydrate): 0.025 mg
Vitamins:
- Inositol: 100 mg
- Thiamine hydrochloride (Vitamin B₁): 1 mg
- Pyridoxine hydrochloride (Vitamin B₆): 0.5 mg
- Nicotinic acid (Vitamin B₃): 0.5 mg
Carbon Source:
- Sucrose (as a carbon source, required for plant cell metabolism): 20,000 mg (2%)
Agar (optional for solid medium):
- Agar: 7,000-8,000 mg (typically 0.7–0.8% for solidifying the medium)
pH Adjustment:
- The pH of the medium should be adjusted to around 5.8 before autoclaving (sterilization).
Growth Regulators (Optional):
- Eriksson’s Medium alone provides a broad spectrum of nutrients but, in practice, plant growth regulators (such as auxins, cytokinins, or gibberellins) are often added to direct plant morphogenesis or callus induction.
How Eriksson’s Medium Supports Plant Tissue Growth
The unique formulation of macronutrients, including NH₄NO₃ and KNO₃, provides a balanced source of nitrogen, essential for cell division and growth. The micronutrients supply key enzymes and cofactors that assist in various metabolic functions. Iron, delivered in the form of a chelated complex (EDTA), is necessary for chloroplast development and photosynthesis. Vitamins like thiamine and inositol further support enzymatic activities inside plant cells, while pyridoxine supports metabolic processes related to nitrogen.
Conclusion
Eriksson’s Medium may not be as universally used as the famed Murashige and Skoog (MS) medium, but it’s an excellent choice for specific tissue cultures, especially in studies of algae or experimental in vitro studies on moss and ferns. The unique balance of macro and micronutrients makes it ideal for supporting the complex metabolic and physiological needs of plant cells under in vitro conditions.
Understanding how to select the right culture medium, and knowing the formulation of Eriksson’s Medium, in particular, can significantly contribute to the success of your plant tissue culture experiments. Whether for research purposes, algal studies, or tissue regeneration, Eriksson’s Medium could be the key to unlocking successful plant behavior in a controlled environment.