In botany, pneumatodes describe air-containing structures in roots. [1] Their function is to allow gaseous exchange in root tissues. This can be beneficial to semi-aquatic plants, such as neo-tropical palms. [2] Plants with photosynthetic roots, such as epiphytic orchids like Dendrophylax lindenii also possess these structures. They play a role in fungal interactions. [3]
The name of the structure is derived from the Greek word πνεῦμα (pneûma), meaning breath and ὁδός (hodós), meaning pathway. [4]
Fungal infections of plants may begin through penetration of the roots through pneumatodes. [5]
Pneumatodes are considered as a special type of cyclocytic stomata. The entire structure may rise above the adjacent epidermis. The pneumatodes may function as double structures for gas exchange and liquid water elimination (guttation). [6] Leafless orchids with photosynthetic roots rely on the gas exchange through pneumatodes for photosynthesis.
These structures are characteristic for different species and can be used to differentiate between them. These features can be used to distinguish between palm species. [7] They can also be used in the field of paleobotany, as the structures may be preserved in fossilized roots. [8]
Orchidaceae, commonly called the orchid family, is a diverse and widespread family of flowering plants, with blooms that are often colourful and fragrant.
An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water or from debris accumulating around it. The plants, on which epiphytes grow, are called phorophytes. Epiphytes take part in nutrient cycles and add to both the diversity and biomass of the ecosystem in which they occur, like any other organism. They are an important source of food for many species. Typically, the older parts of a plant will have more epiphytes growing on them. Epiphytes differ from parasites in that they grow on other plants for physical support and do not necessarily affect the host negatively. An organism that grows on another organism that is not a plant may be called an epibiont. Epiphytes are usually found in the temperate zone or in the tropics. Epiphyte species make good houseplants due to their minimal water and soil requirements. Epiphytes provide a rich and diverse habitat for other organisms including animals, fungi, bacteria, and myxomycetes.
In botany, a stoma, also called a stomate, is a pore found in the epidermis of leaves, stems, and other organs, that controls the rate of gas exchange. The pore is bordered by a pair of specialized parenchyma cells known as guard cells that are responsible for regulating the size of the stomatal opening.
Vanda, abbreviated in the horticultural trade as V., is a genus in the orchid family, Orchidaceae. There are about 87 species, and the genus is commonly cultivated for the marketplace. This genus and its allies are considered to be among the most specifically adapted of all orchids within the Orchidaceae. The genus is highly prized in horticulture for its showy, fragrant, long-lasting, and intensely colorful flowers. Vanda species are widespread across East Asia, Southeast Asia, and New Guinea, with a few species extending into Queensland and some of the islands of the western Pacific.
A lenticel is a porous tissue consisting of cells with large intercellular spaces in the periderm of the secondarily thickened organs and the bark of woody stems and roots of dicotyledonous flowering plants. It functions as a pore, providing a pathway for the direct exchange of gases between the internal tissues and atmosphere through the bark, which is otherwise impermeable to gases. The name lenticel, pronounced with an, derives from its lenticular (lens-like) shape. The shape of lenticels is one of the characteristics used for tree identification.
Crassulacean acid metabolism, also known as CAM photosynthesis, is a carbon fixation pathway that evolved in some plants as an adaptation to arid conditions that allows a plant to photosynthesize during the day, but only exchange gases at night. In a plant using full CAM, the stomata in the leaves remain shut during the day to reduce evapotranspiration, but they open at night to collect carbon dioxide and allow it to diffuse into the mesophyll cells. The CO2 is stored as the four-carbon acid malic acid in vacuoles at night, and then in the daytime, the malate is transported to chloroplasts where it is converted back to CO2, which is then used during photosynthesis. The pre-collected CO2 is concentrated around the enzyme RuBisCO, increasing photosynthetic efficiency. This mechanism of acid metabolism was first discovered in plants of the family Crassulaceae.
PhalaenopsisBlume (1825), commonly known as moth orchids, is a genus of about seventy species of plants in the family Orchidaceae. Orchids in this genus are monopodial epiphytes or lithophytes with long, coarse roots, short, leafy stems and long-lasting, flat flowers arranged in a flowering stem that often branches near the end. Orchids in this genus are native to India, Taiwan, China, Southeast Asia, New Guinea and Australia with the majority in Indonesia and the Philippines.
Ansellia is considered a monotypic genus of orchid, with only one species, Ansellia africana, commonly known as African ansellia or leopard orchid, however, it may in fact be a complex group of species which share common floral structure and growth habit.
Catopsis berteroniana, commonly known as the powdery strap airplant or the lantern of the forest, is an epiphytic bromeliad thought to be a possible carnivorous plant, similar to Brocchinia reducta, although the evidence is equivocal. Its native range is from southern Florida to southern Brazil. It generally grows on the unshaded twigs of trees, and has been shown experimentally to trap more insects in its tank than other bromeliads of comparable size. There are several other species in the genus, none of which is believed to be carnivorous.
Velamen or velamen radicum is a spongy, multiple epidermis that covers the roots of some epiphytic or semi-epiphytic plants, such as orchid and Clivia species.
Dendrophylax lindenii, the ghost orchid is a perennial epiphyte from the orchid family (Orchidaceae). It is native to Florida and Cuba. Other common names include palm polly and white frog orchid.
In natural science, subaerial, has been used since 1833, notably in geology and botany, to describe features and events occurring or formed on or near the Earth's land surface. They are thus exposed to Earth's atmosphere. This may be contrasted with subaqueous events or features located below a water surface, submarine events or features located below a sea surface, subterranean events or features located below ground, or subglacial events or features located below glacial ice such as ice sheets.
Epipogium aphyllum, the ghost orchid is a hardy myco-heterotrophic orchid lacking chlorophyll.
Dendrophylax is a genus of leafless neotropical orchids native to Mexico, Central America, the West Indies, and Florida. The name is from Greek δένδρον ("tree") and φύλαξ. One species, Dendrophylax lindenii, featured heavily in the book The Orchid Thief.
Taeniophyllum, commonly known as ribbon roots or 带叶兰属 is a genus of about 240 species of epiphytic or lithophytic plants from the orchid family, Orchidaceae. Plants in this genus are more or less leafless with a very short stem and roots that are often flat, green and photosynthetic. The flowers are small, short-lived, flat or tube-shaped and arranged on short, thin flowering stems. Orchids in this genus are found in Africa, tropical and subtropical Asia, New Guinea, Australia and some Western Pacific Islands.
Angraecinae is a subtribe in the family Orchidaceae. The subtribe consists of approximately 18 genera and about 360 species. The type genus is Angraecum. Most of the genera are endemic to Africa, Madagascar and other Indian Ocean Islands, a few genera can also be found in the Americas.
The mycorrhizosphere is the region around a mycorrhizal fungus in which nutrients released from the fungus increase the microbial population and its activities. The roots of most terrestrial plants, including most crop plants and almost all woody plants, are colonized by mycorrhiza-forming symbiotic fungi. In this relationship, the plant roots are infected by a fungus, but the rest of the fungal mycelium continues to grow through the soil, digesting and absorbing nutrients and water and sharing these with its plant host. The fungus in turn benefits by receiving photosynthetic sugars from its host. The mycorrhizosphere consists of roots, hyphae of the directly connected mycorrhizal fungi, associated microorganisms, and the soil in their direct influence.
Dendrophylax porrectus, the jingle bell orchid, or needleroot orchid, is a species of epiphytic orchid native to Mexico, El Salvador, Guatemala, Florida, Cayman Islands, Cuba, Hispaniola, Jamaica, and Puerto Rico.
Orchid mycorrhizae are symbiotic relationships between the roots of plants of the family Orchidaceae and a variety of fungi. Nearly all orchids are myco-heterotrophic at some point in their life cycle. Orchid mycorrhizae are critically important during orchid germination, as an orchid seed has virtually no energy reserve and obtains its carbon from the fungal symbiont.
Michael Jeffrey Balick is an American ethnobotanist, economic botanist, and pharmacognosist, known as a leading expert on medicinal and toxic plants, biocultural conservation and the plant family Arecaceae (palms).
 | This article needs additional or more specific categories .(March 2022) |