What Is A Pseudobulb In Orchids?
A pseudobulb is a plant part which resembles a small flower but does not have any flowers. They are commonly found in the family Apiaceae (orchid) and include species such as the common dahlia, daisy, dogwood, hyacinth, lily of the valley and many others. They are sometimes called “pseudo-flowers” because they resemble flowers but do not actually produce seeds.
The word “pseudobulb” comes from the Greek words pseudein (“to hide”) and boulos (“flower”). The Latin name for these plants was “pseudo-dahlias”.
There are two main types of pseudobulbs: those with only one petal, and those with two petals. There are also some that have three petals. Some pseudobulbs have no sepals at all.
Pseudobulbs with only one petal are often referred to as “true” orchids, while those with two petals are known as “false” orchids. True orchids usually grow in groups of several plants and may even form clumps, whereas false orchid varieties tend to grow alone and look like single flowers.
Pseudobulbs also come in various shapes. When cut open, they may reveal a spongy mass with small tubular cavities and narrow channels. This mass (known as the “bulb”) sometimes has fleshy roots or root hairs growing from it. The purpose of a bulb is to store nutrients for the plant to use when conditions are too dry or otherwise unfavourable.
Some orchids can survive for years without putting forth leaves, storing all their energy in the bulb to see them through dry spells.
Some pseudobulbs do not have bulbs, but these may be swollen bases of stem with no leaves. A few species have “pseudobulbs” that are not at all like those described above; instead of being swollen stems or roots, they are more like leaves folded up to look like a bulb or even a seed pod.
Orchids with pseudobulbs include members of the following orchid genera: Aplectrum, Bletilla, Calanthe, Cattleya, Coelogyne, Encyclia, Eria, Oeonia, Orchis, Platystele, Rhyncostylis, Sacoila and Triphora.
These plants are epiphytes. They have fleshy roots and may lack any chlorophyll, although they are not parasites. They grow on other plants, usually trees, in the moist forests of tropical regions. About 2000 species of orchids have this growth habit, but it is more common in the tropics than in temperate zones.
Found more commonly at lower altitudes than other orchid types, these plants can be found growing on rocks or tree branches. They are more common in the subtropical and tropical zones (excluding the equator), but they can also be found at higher latitudes in areas that don’t experience freezing temperatures. Many epiphytes have aerial roots that can help them cling to tree branches or rocks.
Some epiphytes, such as many species of Cattleya, grow pseudobulbs. These growths resemble thick, short stems and store nutrients for the plant. They may act as a storage organs that can allow the orchid to survive periods of drought.
Other epiphytes, such as the species in the genus Hapalorchis, grow neither pseudobulbs nor aerial roots. These plants are also known as “twig orchids” due to their shape and habit of growing on twigs.
These orchids are usually found on trees in humid forests. They can also be found in other kinds of habitats, such as swamps and marshes, provided there is plenty of water. The roots of these plants require wet soil to grow.
The leaves of these orchids have a special window that helps them absorb more sunlight. They are often hidden beneath the thick leaves of the trees on which they grow, so they get only indirect sunlight. Without the ability to make their own food, these plants obtain all the nutrients they need from the air.
These plants are commonly found at low altitudes, in swamps and marshes. They can also be found in other kinds of moist habitats. These orchids are parasites that get all the nutrients they need from other plants. They lack roots and leaves, but instead have thick stems that store nutrients.
These plants grow on rocks or tree branches in dry, open areas. They are most commonly found in the temperate zones, but can also be found at higher latitudes in the Southern Hemisphere. They need a certain amount of direct sunlight each day to synthesize food from air and water.
They have thick, waxy leaves that help them retain moisture. They can grow in very dry conditions because of this, as well as their thick, fleshy roots that allow them to access water deep in the ground.
These plants have flowers that hang upside-down. They get most of their nutrients from decaying matter that falls on top of them, instead of directly from soil.
Sources & references used in this article:
What does morphology tell us about orchid relationships?—A cladistic analysis by JV Freudenstein, FN Rasmussen – American Journal of Botany, 1999 – Wiley Online Library
Effects of light intensity and temperature on growth, flowering, and single-leaf CO2 assimilation in Odontioda orchid by 窪田聡， 山本淳子， 高沢容子， 逆井肇， 渡部一夫… – 園芸学会雑誌, 2005 – jlc.jst.go.jp
Vegetative propagation of orchids by YI Lee – Orchid Propagation: From Laboratories to …, 2018 – Springer