Overview:
Parmotrema sulphuratum (Nees & Flotow) Hale is a species of foliose lichen belonging to the family Parmeliaceae. This lichen is primarily found in the tropical regions of Africa, Asia, Australia, and Central and South America.
Common Names:
Some of the common names used for Parmotrema sulphuratum are sulfur shield lichen, sulphur colored shield lichen, and yellow shield lichen.
Appearance:
Parmotrema sulphuratum has a distinctive yellowish-green coloration that sets it apart from other lichen species. The lichen body is foliose, which means that it has a flat and leaf-like shape. It grows to a size of around 15-20 centimeters and has an irregular lobed margin. The surface of the lichen body is covered with a sorediate layer, which is a powdery substance that contains fungal and algal cells. This layer helps the lichen to spread and reproduce.
Uses:
Parmotrema sulphuratum is used in traditional medicine for various purposes. In some parts of Africa, it is used to treat jaundice, stomachaches, and liver problems. The lichen is also used as a source of food for certain insects and animals. Some studies have shown that the lichen has antibacterial and antifungal properties, which makes it a potential source of natural drugs.
Light requirements
As a foliose lichen, Parmotrema sulphuratum requires moderate light levels for optimal growth. Direct sunlight can damage the thalli and reduce their ability to photosynthesize, while too little light can limit growth and reproduction.
Temperature requirements
Parmotrema sulphuratum grows best in mesic (moderately moist) environments, with temperatures ranging from 15-25°C. In hotter or drier environments, the lichen may become desiccated and cease growing.
Soil requirements
As a lichen, Parmotrema sulphuratum does not grow in soil. Instead, it grows on rocks, bark, or other substrates, often in epiphytic (tree-dwelling) habitats. The specific substrate type can influence the lichen's growth rate and morphology.
Cultivation methods
Parmotrema sulphuratum is a lichen species that grows naturally on the bark of trees. Cultivating it is more complicated than growing other types of plants. To culture this lichen, you must prepare a substrate that mimics the conditions found in its natural habitat. This will entail introducing more than one type of substrate like branches, twigs, and even soil.Watering needs
Parmotrema sulphuratum doesn't require much watering. As a lichen, it obtains nutrients through photosynthesis and absorption from the atmosphere. Watering can be done by misting the culture regularly, ensuring the substrate remains moist but not waterlogged. The depth of the mist should be such that water doesn't remain on the substrate surface for too long.Fertilization
Unlike other plants, Parmotrema sulphuratum doesn't require regular feeding or fertilization. The lichen gets its nutrients from the environment through photosynthesis and respiration. However, you can add substrate components that provide essential nutrients like phosphorous, potassium, and nitrogen. You can use a substrate that has soil or another organic fertilizer that slowly releases nutrients, promoting healthy growth.Pruning
The only aspect of Parmotrema sulphuratum that requires pruning is cutting the twigs or branches used as the substrate to fit the size of the growing container. When pruning the substrate material, ensure you don't damage the thallus, which is vital for photosynthesis and nutrient absorption. Additionally, removing any dead or diseased portions of the lichen will promote healthy growth. This can be done by carefully peeling off the affected parts using a pair of tweezers or a sharp blade.Propagation of Parmotrema sulphuratum
Propagating Parmotrema sulphuratum can be challenging, but not impossible. The plant can be propagated through fragmentation and spores.
Fragmentation
Fragmentation involves dividing the thallus into smaller pieces and attaching them onto a substrate. To propagate Parmotrema sulphuratum through fragmentation, select a healthy thallus and use a sterilized blade to cut it into smaller pieces. Ensure that each piece has at least one attachment point, which is usually the rhizome. Moist the surface of the substrate, place the fragments on it, and mist the fragments with sterile water. Cover the fragments with a clear lid to maintain humidity and avoid desiccation. Place the setup in an area with dappled light and maintain moisture levels. After some weeks, the fragments will attach to the substrate and start growing.
Spores
Propagating Parmotrema sulphuratum through spores is more challenging and requires specific conditions. The spores are usually produced in the apothecia, which are the reproductive structures of the plant. To collect the spores, harvest the thalli with mature apothecia and place them in a paper bag. Let the bag sit in a dry area for some days to allow the apothecia to release the spores. Collect the spores and sterilize them with ethanol. Sow the spores onto a substrate, usually a mixture of soil and sand, and moisten it with sterile water. Cover the container with a clear lid to maintain humidity and avoid desiccation. Place the container in an area with indirect light and maintain moisture levels. After some weeks, the spores will germinate and start growing into thalli.
Disease Management
Parmotrema sulphuratum (Nees & Flotow) Hale is a lichen species that typically does not suffer from any major diseases, but it might face some problems due to environmental changes. Overexposure to pollutants, improper temperature, and humidity levels might create stressful conditions, leading to reduced growth and development. In case of any adverse symptoms like browning, drying, or discoloration, it is essential to investigate further to identify the cause and take corrective measures promptly.
The management of lichen diseases is usually challenging because they represent a symbiotic relationship between a fungal host and an algal or cyanobacterial partner. Any intervention should be focused on maintaining optimal environmental conditions by reducing the effects of pollution and providing enough air circulation, light, and moisture. Applying fungicides or pesticides to lichens is hardly possible due to their particular structure, which prevents the penetration of external agents.
Pest Management
Although Parmotrema sulphuratum is not commonly affected by pests or insects, some disturbances might arise, especially when it grows in artificially modified environments like gardens, greenhouses, or indoor terrariums. Pest infestation might affect the lichen's health, leading to reduced photosynthesis, respiration, and energy storage.
The most common pests that might attack lichens are mites, aphids, mealybugs, and scale insects. To manage these pests, the first step is to detect their presence early by visually inspecting the plant for any signs of damage or droppings. Using a soft-bristled brush, it is possible to remove the insects manually, or by applying pressurized water sprays.
In case of a severe infestation, it is essential to consult a professional pest control service that can offer specialized treatments that do not harm the lichen's structure or alter its ecology. Chemical insecticides or pesticides should be avoided because they might do more harm than good, affecting other beneficial insects and microorganisms in the lichen's ecosystem.
