Wavelengths of Light for Anthuriums

Light of different wavelengths has a significant influence on the physiological and biochemical processes in plants, especially on photosynthesis and photomorphogenetic development.
The wavelengths of the visible spectrum, typically between 380nm and 750nm, are of particular importance because they are absorbed and processed by the plant photoreceptors. The following is an analysis of the wavelength ranges and their specific functions:

1. blue light (400-500nm)

• Effect: The blue spectrum is strongly absorbed by the photoreceptors cryptochrome and phototropin. It influences the regulation of stomata, phototrophic growth and the synthesis of secondary metabolites.
• Importance for photosynthesis: Chlorophyll efficiently absorbs blue light and is therefore essential for primary production. It promotes compact growth by inhibiting cell elongation.
• Application: Blue light is particularly important in the vegetative growth phase and is often used in combination with other wavelengths.

2. red light (600-700nm)

• Effect: It is mainly absorbed by chlorophyll a and b and is therefore one of the most efficient wavelengths for photosynthesis. It also interacts with the phytochrome system, which regulates germination, flowering and photoperiodic responses, among others.
• Importance for development: Red light induces flowering and improves the energy efficiency of photosynthesis.
• Application: Important in the flowering and fruiting phase; in combination with blue light to maximize biomass production.

3. green light (500-600nm)

• Effect: Green light is less absorbed by chlorophyll, but penetrates into deeper layers of the leaf tissue and enables photosynthesis in the subepidermal cells.
• Functional role: Complements other wavelengths of light and improves spectral balance in artificial lighting systems.
• Application: Less effective than blue and red light, but important for regulating light scattering and leaf canophoria.

4. UV light (below 400nm)

• Effect: UV-A (315-400nm) promotes the synthesis of flavonoids and phenolic compounds, which serve as protective mechanisms against UV stress. UV-B (280-315nm) has a lower penetration depth, but regulates DNA repair mechanisms and activates stress signals.
• Risks: Excessive UV exposure can cause cell damage, so controlled dosing is required.
• Applications: Selective UV irradiation to improve the formation of secondary plant substances, especially in medicinal and useful plants. 

5. far red light (700-750nm)

• Effect: Influences plant morphogenesis via the ratio of active phytochrome (Pfr) to inactive phytochrome (Pr), including shade avoidance responses and flowering induction.
• Combination with red light: Supports synergistic effects in controlling growth cycles and adapting to the light environment.
• Application: Particularly relevant for the control of the developmental phases of long-day and short-day plants.

The spectral quality of light is a crucial factor in optimizing plant growth and development. In practice, a combination of blue and red light is often used, although specific additions such as UV and far-red light can be integrated depending on the objective. Modern LED technologies enable the targeted provision of the required wavelengths to maximize photosynthetic efficiency and crop quality.