Origin and Common Names
Parmotrema ultralucens (Krog) Hale is a species of lichen that belongs to the family Parmeliaceae. The plant is native to South America and can be found growing on trees, rocks, and soil surfaces in various environments. The common names for Parmotrema ultralucens include barba de viejo (Spanish for "old man's beard") and croa preta (Portuguese for "black crust").
General Appearance
Parmotrema ultralucens has a thallus that is pale greenish-grey in color, with numerous narrow, flat branches that grow in an irregular pattern. It forms dense mats on the surface it grows on, which can measure up to several centimeters in thickness. The underside of the thallus has a black coloration that is earthy in texture, with rhizine bundles that end in black to brown fibrils. The lichen can reach up to 15 cm in diameter and has a sorediate surface.
Uses
Parmotrema ultralucens can be utilized for various purposes, including bioprospecting, antifungal, and antimicrobial activities. Extracts from the plant are rich in secondary metabolites, such as atranorin, salacinol, and usnic acid, which have been shown to exhibit biological activities that are useful in agriculture, medicine, and the biotechnology industry. The lichen has been used extensively in traditional medicine to treat ailments such as inflammation, stomach disorders, and respiratory diseases.
Growth Conditions of Parmotrema ultralucens (Krog) Hale
Parmotrema ultralucens is a foliose lichen that belongs to the family Parmeliaceae. It is commonly found growing on tree branches in tropical and subtropical regions. The following are the growth conditions required for the healthy growth of Parmotrema ultralucens.
Light Requirements
Parmotrema ultralucens requires moderate to high levels of light for healthy growth. It can tolerate some shade, but it grows best in bright filtered sunlight. Direct sunlight should be avoided as it can damage the thallus and reduce its growth rate. In natural conditions, it is often found growing on the upper side of tree branches where it receives ample sunlight.
Temperature Requirements
Parmotrema ultralucens grows best in warm and moist environments. It can tolerate a wide range of temperatures from 20°C to 35°C. However, it prefers temperatures between 25°C to 30°C. It cannot survive in extremely hot or cold temperatures and will show stunted growth in such conditions.
Soil Requirements
Parmotrema ultralucens is a epiphytic lichen, meaning that it does not require soil to grow. Instead, it grows on the surface of trees, rocks, or other substrates. It prefers substrates that are not too acidic or alkaline. It can tolerate a pH range of 5.0 to 7.0, but its growth rate reduces beyond this range. The substrate should be able to hold moisture, but it should not be waterlogged.
Cultivation
Parmotrema ultralucens is a lichen species that typically grows in subtropical to tropical environments. It can be cultivated on a variety of substrates, such as rocks, trees, and soil. The best way to cultivate this species is by locating an area with ample sunlight and warm temperatures.
Watering Needs
While Parmotrema ultralucens does require regular watering, it is important not to overwater the plant. The species can tolerate some drought, but it prefers consistent moisture. It is essential to avoid direct sunlight on the plant, as it can cause the moisture to evaporate quickly and leave the plant vulnerable to damage.
Fertilization
This species of lichen does not require fertilization. In fact, it is best to avoid any fertilizers or chemicals, as they may harm or kill the plant. Instead, the plant depends on natural nutrients and moisture from the environment.
Pruning
Pruning isn't necessary for Parmotrema ultralucens. The plant is a lichen that does not grow stalks, stems, or leaves. It maintains a low profile and tends to spread out over rocks or trees. However, if there is a buildup of debris or leaf litter surrounding the plant, it is best to clean it up to prevent smothering or damage from pests.
Propagation of Parmotrema ultralucens
Parmotrema ultralucens (Krog) Hale, commonly known as "Light-loving Parmotrema" is a leafy lichen. Parmotrema ultralucens reproduces both asexually and sexually and is adaptable to a wide range of environments.
Asexual Propagation
Parmotrema ultralucens asexually reproduces through fragmentation or the breaking off of a piece of the thallus. This portion of the thallus can then be transplanted onto another surface, preferably one with a similar substrate. Ideally, the surface should be moist, windy and have shaded sunlight.
Sexual Propagation
Parmotrema ultralucens sexually reproduces through spores called Ascospores, which are produced in small, circular disk-like structures on the thallus surface called apothecia. Once an apothecia is mature, it releases spores onto the surrounding area. These spores end up as new individuals if the conditions are right. Conditions that are conducive to germination for Parmotrema ultralucens spores include moist surfaces, good air circulation and low to medium light conditions.
Propagation through sexual means can be particularly slow, so asexual propagation tends to be more preferred and more commonly used.
Disease Management
Plant Parmotrema ultralucens is susceptible to various diseases that can lead to significant damages if not addressed timely. Here are some common diseases that can affect Parmotrema ultralucens, along with their management:
Leaf Spot
Leaf spot is one of the most common diseases that affect Parmotrema ultralucens. It is characterized by the development of small, circular, or oval-shaped spots on the leaves. The spots may vary in color from yellow, brown, black, or gray, depending on the pathogen that causes it. Leaf spot can cause defoliation, stunted growth, and poor plant health. To manage this disease, you should:
- Remove all infected leaves and debris around the plant
- Avoid overcrowding by planting Parmotrema ultralucens at an appropriate distance from each other
- Ensure proper drainage to prevent standing water around the roots
- Apply a fungicide such as copper-based fungicides to the affected leaves
Anthracnose
Anthracnose is another common disease that affects Parmotrema ultralucens. It is caused by the fungal pathogen Colletotrichum spp. and is characterized by the development of dark, sunken spots on leaves, stems, and fruits. Infected leaves may also develop yellow or brown necrotic areas that can cause defoliation and stunt growth. To manage this disease, you should:
- Remove all infected plant debris
- Prune infected branches and stems during dry weather to avoid spreading the pathogen
- Avoid overhead watering to prevent creating a moist environment that favors fungal growth
- Apply a copper-based fungicide to the affected areas, following the manufacturer's recommendations
Pest Management
Plant Parmotrema ultralucens is also prone to several pests that can cause considerable damage to the plant. Here are some common pests that can affect Parmotrema ultralucens, along with their management:
Spider Mites
Spider mites are tiny pests that can cause significant damage by sucking sap from the leaves, leading to discoloration and distortion. The infested leaves may also develop tiny webs. To manage spider mites, you should:
- Spray the infected leaves with a strong jet of water to dislodge and rinse off the mites
- Introduce predatory insects such as ladybugs and lacewings that feed on spider mites
- Use insecticidal soap, following the manufacturer's instructions
Scale Insects
Scale insects are small, immobile pests that feed on the sap of Parmotrema ultralucens, causing stunted growth and yellowing of the leaves. They secrete a protective waxy layer that shields them from predators and chemicals. To manage scale insects, you should:
- Scrub off the scales carefully with a soft-bristled brush or cloth dipped in soapy water
- Introduce natural predators such as ladybugs, lacewings, and parasitic wasps that feed on the scales
- Use horticultural oil or neem oil, following the manufacturer's recommendations
