A ligule (from Latin: ligula “strap”, variant of lingula, from lingua “tongue”) is a thin outgrowth at the junction of leaf and leafstalk of many grasses (Poaceae) and sedges. A ligule is also a strap-shaped extension of the corolla, such as that of a ray floret in plants in the daisy family Asteraceae.
What is ligule in plants?
: a scalelike projection especially on a plant: such as. a : a thin appendage of a foliage leaf and especially of the sheath of a blade of grass. b : a ligulate corolla of a ray floret in a composite head.
What is ligule and auricle?
is that ligule is (botany) in many grasses (poaceae) and some sedges (cyperaceae), the membranous appendage or ring of hairs projecting from the inner side of a leaf at the junction between the blade and the sheath while auricle is (botany) any appendage in the shape of an earlobe.
What is the structure of ligule?
The ligule is considered to be a highly organized and differentiated leaf organ with a pholosynthetic mesophyll and an adaxial epidermis active in the synthesis of protein and polysaccharide.
What forms can a ligule take?
The ligule is an extra piece of tissue that forms at the growth point. I like to think of it as a “cuticle” that forms as the leaf blade grows. These ligules can be smooth or shaggy, pointed or flat. There are many, many different ways the ligule can take shape.
Where we can see ligule in Selaginella?
A small, membranous, tongue-like structure, ligule (latin ligula = a small tongue), is located at the base of each vegetative, leaf and sporophyll (Fig. 7.51). The ligule is found on the ventral (upper) surface of the leaf.
Does Lycopodium have a ligule?
lycophytes. …a leaf; this is the ligule, a peculiar tonguelike outgrowth from the leaf surface near the leaf base. Leaves of Lycopodium and Selaginella can be differentiated on this basis. The ligule, which appears very early in the development of a leaf, is a surprisingly complex structure at maturity.
Is ligule present in Lycopodium?
Note: In Lycopodium there is a ligule, a strange tongue-like outcrop from the surface of the leaf at the base of the leaf. Leaves of Lycopodium and Selaginella can be distinguished on this basis. The ligule, which occurs very early in the growth of the leaf, is surprisingly complex at maturity.
Do all grasses have ligules?
Ligules and Auricles
None of the cool-season turfgrasses have ligules that appear as a fringe of hairs, but this feature is common on many weed grasses and most warm-season turfgrasses.
What is leaf sheath?
noun. botany the basal part of a grass leaf that encircles the stem.
What are Auricles on grass?
Definition: Used for identifying different types of grass, depending on the shape and presence. An auricle is typically a short claw-shaped, rounded, or pointed attachment at the base of a leaf blade, which tends to attach the lower part of the leaf to the stem of the leaf or blade.
What is the function of ligule in selaginella?
The ligule is specialized for the production and secretion of extracellular mucilage. The ligule is a structure on the adaxial surface of the microphylls and sporophylls of Selaginella and consists of apical, basal, glossopodial, and sheath cells.
What do you mean by Ramenta?
ramenta. (Science: botany) thin brownish chaffy scales upon the leaves or young shoots of some plants, especially upon the petioles and leaves of ferns. Origin: L, scrapings.
Does grass have hair?
At the base of the grass plant, roots grow down into the earth. Typically, grass roots are fibrous, or threadlike. … In most grasses, a ligule surrounds the connection between the sheath and the blade. A ligule can take the form of a thin membrane or a fringe of hair-like projections.
What is the occurrence of Lycopodium?
They are found in colder arctic region as well as in temperate, tropical and sub-tropical regions but they are abundantly found in tropical zones. Thirty three species of Lycopodium have been reported from India. Mostly it is found growing in moist and shady places which are rich in humus and other organic matters.
What is true Lycopodium?
They are flowerless, vascular, terrestrial or epiphytic plants, with widely branched, erect, prostrate, or creeping stems, with small, simple, needle-like or scale-like leaves that cover the stem and branches thickly. The leaves contain a single, unbranched vascular strand, and are microphylls by definition.
Does Selaginella have Microphylls?
Description. Selaginella species are creeping or ascendant plants with simple, scale-like leaves (microphylls) on branching stems from which roots also arise. … In Selaginella, each microphyll and sporophyll has a small scale-like outgrowth called a ligule at the base of the upper surface.
Why is fern called pteridophyta?
Because pteridophytes produce neither flowers nor seeds, they are sometimes referred to as “cryptogams”, meaning that their means of reproduction is hidden. Ferns, horsetails (often treated as ferns), and lycophytes (clubmosses, spikemosses, and quillworts) are all pteridophytes.
Which is absent leaf of Selaginella?
Because Selaginella has both microspores and megaspores, the plant is called heterosporous. They have a different type of leaf so it has heterophylly. The leaf bears on its upper surface near its base a small, membranous, tongue-like outgrowth called the ligule.
Does selaginella have ligules?
In Selaginella, each microphyll and sporophyll has a small scale-like outgrowth called a ligule at the base of the upper surface. The plants are heterosporous with spores of two different size classes, known as megaspores and microspores. Under dry conditions, some species of Selaginella can survive dehydration.
What is a petiole on a leaf?
A plant leaf is generally composed of a petiole and a leaf blade. The petiole connects the leaf blade to the plant stem and, from a structural viewpoint, it resembles a cantilever beam.
What is the function of Auricles in plants?
The auricle, which acts as a hinge allowing the leaf blade to project at an angle from the vertical stem, might also affect LA, although this has not been demonstrated.