Punctelia subpraesignis (Nyl.) Krog: Description
Punctelia subpraesignis, also known as Lungwort Lichen, is a foliose lichen belonging to the family Parmeliaceae. This lichen is commonly found in North America, Europe, and Asia on old trees, rocks, or soil.
General Appearance
The thallus of Punctelia subpraesignis is foliose and can grow up to 10-20 cm in diameter. The upper surface is pale greenish-grey or bluish-grey when dry and dark green when wet. The lower surface is cream-colored with small pores scattered over it. The lobe margins are irregularly cleft or lacerate, and the tips are rounded or slightly pointed.
Uses
Punctelia subpraesignis contains various bioactive compounds, including usnic acid and atranorin. These compounds have been shown to possess antimicrobial, anti-inflammatory, and antioxidant properties. Indigenous people have used this lichen to treat respiratory ailments, such as cough, asthma, and tuberculosis. It has also been used as a natural dye for wool and leather.
Growth Conditions for Punctelia subpraesignis (Nyl.) Krog
Punctelia subpraesignis (Nyl.) Krog is a species of foliose lichen commonly found in North America. To grow and develop optimally, this species requires specific environmental conditions regarding light, temperature, and soil.
Light Requirements
Punctelia subpraesignis needs a moderate amount of indirect light to thrive. Direct sunlight can be harmful to the lichen, leading to excessive drying out and damage to the photosynthetic machinery. It grows best in a shaded or partially shaded area where it can receive enough light without being exposed to direct sun rays. In the wild, it can be found growing on tree trunks or branches under a dense canopy of leaves.
Temperature Requirements
The temperature range required for the growth of Punctelia subpraesignis is diverse. This lichen species can grow in a variety of climates ranging from cool, moist environments to arid regions. Generally, it prefers a cool and damp environment, with a temperature range between 10-25°C (50-77°F). At temperatures above 30°C (86°F), growth can be inhibited, causing dehydration and a decrease in the photosynthetic rate essential for survival.
Soil Requirements
The soil or substrate is an essential factor facilitating the growth of Punctelia subpraesignis. This lichen requires a stable substrate rich in nutrients and minerals to adhere and establish. It can be found growing on bark, rock, or soil surfaces, and it doesn't tolerate polluted or acidic environments. It also requires an adequate amount of moisture to grow well and exhibit nutrients' uptake and utilization from the substrate.
In conclusion, Punctelia subpraesignis needs a moderate amount of indirect light, a temperature range between 10-25°C (50-77°F), and a stable, nutrient-rich substrate to grow well. These environmental factors should be optimal and consistent for the lichen's growth and development to thrive.
Cultivation methods
Punctelia subpraesignis is a lichen plant that grows on tree bark and rocks. It can also be cultivated indoors by using suitable substrate (tree bark, rocks, or stones) and maintaining appropriate environmental conditions.
The best time to cultivate this plant is in the spring and summer, where the temperature is warm and humid. The plant should be placed in a bright area with indirect sunlight and well-ventilated space to prevent stagnant air.
Watering needs
Punctelia subpraesignis needs to be watered regularly to keep it hydrated. The substrate should be misted with water every two to three days, and the plant should be watered once a week with distilled water.
It's important not to overwater the plant, as this can cause root rot and other problems. The substrate should be moist but not waterlogged.
Fertilization
Punctelia subpraesignis doesn't require regular fertilization. However, you can use a mild liquid fertilizer with low nitrogen content every 4-6 weeks during the growing season.
It's important not to apply too much fertilizer as this can damage the plant and its growth.
Pruning
Punctelia subpraesignis doesn't require pruning like other plants, as it's a lichen and doesn't have proper leaves or stems. However, it's essential to remove any dead or brown tissue to prevent any harmful fungi or bacteria from infecting the plant.
It's important to use sterilized scissors or sharp blades to remove any dead tissue without damaging the healthy ones.
Propagating Punctelia subpraesignis
Punctelia subpraesignis is a lichen species that generally grows on the bark of trees or rocks. It is commonly found across North America and Europe. Propagation of this species can be done in several ways, as listed below:
Vegetative Propagation
Vegetative propagation of Punctelia subpraesignis can be carried out by fragmentation of the thallus. In this method, parts of the thallus are taken and then attached to new substrates. The fragments need to be compact and free of any airborne contamination. It's important to note that the success rate of this method is highly dependent on the level of fragmentation- the smaller the fragments the longer it takes for the thallus to spread and develop fully.
Spore Propagation
Propagation of the Punctelia subpraesignis species can also be done by spore dispersal. This involves collecting the spores of the species which can be carried out using air, water or an aerodynamic method. The spores are then transferred to new substrates that are conducive to their growth.
Tissue Culture
In tissue culture, small amounts of the species are extracted and cultivated in the laboratory. This method ensures that the newly propagated lichens are free of any bacteria or fungal infections. The success rate of tissue culture varies depending on the substrates used and the conditions of the culture medium.
Disease Management
Punctelia subpraesignis is susceptible to several diseases, including:
- Lichen spot disease: caused by the fungus Lichenomyces puncteliae, this disease causes small spots on the thallus of the plant. It can be managed by removing infected parts of the plant and spraying fungicides.
- Phytophthora root rot: caused by the fungus-like microorganism Phytophthora, this disease causes rotting of the roots and can lead to stunted growth and death of the plant. It can be managed by improving drainage and avoiding over-watering.
- Anthracnose: caused by the fungus Colletotrichum gloeosporioides, this disease causes dark spots and cankers on the bark of the plant. It can be managed by pruning infected branches and spraying with fungicides.
Pest Management
Pests that commonly affect Punctelia subpraesignis include:
- Lichen mites: these pests feed on the thallus of the plant and can cause significant damage. They can be managed by pruning infected parts of the plant and spraying with miticides.
- Snails and slugs: these pests can feed on the thallus of the plant and cause significant damage. They can be managed by handpicking and using traps or baits.
- Caterpillars: the larvae of some moths can feed on the thallus of the plant and cause significant damage. They can be managed by handpicking and using biological controls such as Bacillus thuringiensis.
