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Mairia Hirsuta
''Mairia'' is a genus of Perennial plant, perennial herbaceous plants assigned to the family Asteraceae. All species have leathery, entire or toothed leaves in Rosette (botany), rosettes, directly from the underground rootstock, and one or few flower heads sit at the top of the stems that carry few bracts. These have a whorl of white to mauve ray florets surrounding yellow disc florets in the centre. In general, flowering only occurs after the vegetation has burned down. The six species currently assigned to ''Mairia'' are endemic to the Western Cape and Eastern Cape provinces of South Africa. Some of the species are called fire daisy in English and vuuraster in Afrikaans. Description ''Mairia'' consists of species which store their reserves in their succulent brown underground roots (so-called geophytes). They have evergreen, broad to narrow, oval, elliptic or line-shaped, leathery, often more or less succulent leaves, narrowed at their base in to a Petiole (botany), leaf stalk ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nees
Christian Gottfried Daniel Nees von Esenbeck (14 February 1776 – 16 March 1858) was a prolific German botanist, physician, zoologist, and natural philosopher. He was a contemporary of Goethe and was born within the lifetime of Linnaeus. He described approximately 7,000 plant species (almost as many as Linnaeus himself). His last official act as president of the German Academy of Natural Scientists Leopoldina was to admit Charles Darwin as a member. He was the author of numerous monographs on botany and zoology and majority of his best-known works deal with fungi. Biography Nees von Esenbeck was born in Schloss Reichenberg near Reichelsheim (Odenwald) in Hesse, Germany. He showed an early interest in science and, after receiving his primary education in Darmstadt, went on to the University of Jena and obtained his degree in biology (natural history) and medicine in 1800. He practiced as a physician for Francis I (Erbach-Erbach), but he had developed a great inte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geophyte
A storage organ is a part of a plant specifically modified for storage of energy (generally in the form of carbohydrates) or water. Storage organs often grow underground, where they are better protected from attack by herbivores. Plants that have an underground storage organ are called geophytes in the Raunkiær plant life-form classification system.; reprinted (1977) in ''History of ecology'' series, New York: Arno Press, Storage organs often, but not always, act as perennating organs which enable plants to survive adverse conditions (such as cold, excessive heat, lack of light or drought). Relationship to perennating organ Storage organs may act as perennating organs ('perennating' as in perennial, meaning "through the year", used in the sense of continuing beyond the year and in due course lasting for multiple years). These are used by plants to survive adverse periods in the plant's life-cycle (e.g. caused by cold, excessive heat, lack of light or drought). During these per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cypsela (botany)
Asteraceae () is a large family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the order Asterales. The number of species in Asteraceae is rivaled only by the Orchidaceae, and which is the larger family is unclear as the quantity of extant species in each family is unknown. The Asteraceae were first described in the year 1740 and given the original name Compositae. The family is commonly known as the aster, daisy, composite, or sunflower family. Most species of Asteraceae are herbaceous plants, and may be annual, biennial, or perennial, but there are also shrubs, vines, and trees. The family has a widespread distribution, from subpolar to tropical regions, in a wide variety of habitats. Most occur in hot desert and cold or hot semi-desert climates, and they are found on every continent but Antarctica. Their common primary characteristic is compound flower heads, technically known as capitula, consisting of sometimes hundreds of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehiscence (botany)
Dehiscence is the splitting of a mature plant structure along a built-in line of weakness to release its contents. This is common among fruits, anthers and sporangia. Sometimes this involves the complete detachment of a part. Structures that open in this way are said to be dehiscent. Structures that do not open in this way are called indehiscent, and rely on other mechanisms such as decay, digestion by herbivores, or predation to release the contents. A similar process to dehiscence occurs in some flower buds (e.g., '' Platycodon'', '' Fuchsia''), but this is rarely referred to as dehiscence unless circumscissile dehiscence is involved; anthesis is the usual term for the opening of flowers. Dehiscence may or may not involve the loss of a structure through the process of abscission. The lost structures are said to be caducous. Association with crop breeding Manipulation of dehiscence can improve crop yield since a trait that causes seed dispersal is a disadvantage for fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stamen
The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament and an anther which contains sporangium, microsporangia. Most commonly, anthers are two-lobed (each lobe is termed a locule) and are attached to the filament either at the base or in the middle area of the anther. The sterile (i.e. nonreproductive) tissue between the lobes is called the Connective (botany), connective, an extension of the filament containing conducting strands. It can be seen as an extension on the dorsal side of the anther. A pollen grain develops from a microspore in the microsporangium and contains the male gametophyte. The size of anthers differs greatly, from a tiny fraction of a millimeter in ''Wolfia'' spp up to five inches (13 centimeters) in ''Canna iridiflora'' and ''Strelitzia nicolai''. The stamens in a flower ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ovary (botany)
In the flowering plants, an ovary is a part of the female reproductive organ of the flower or gynoecium. Specifically, it is the part of the pistil which holds the ovule(s) and is located above or below or at the point of connection with the base of the petals and sepals. The pistil may be made up of one carpel or of several fused carpels (e.g. dicarpel or tricarpel), and therefore the ovary can contain part of one carpel or parts of several fused carpels. Above the ovary is the Style (botany), style and the stigma, which is where the pollen lands and germinates to grow down through the style to the ovary, and, for each individual pollen grain, to fertilize one individual ovule. Some wind pollinated flowers have much reduced and modified ovaries. Fruits A fruit is the mature, ripened ovary of a flower following double fertilization in an angiosperm. Because gymnosperms do not have an ovary but reproduce through fertilization of unprotected ovules, they produce naked seeds th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Floral Symmetry
Floral symmetry describes whether, and how, a flower, in particular its perianth, can be divided into two or more identical or mirror-image parts. Uncommonly, flowers may have no axis of symmetry at all, typically because their parts are spirally arranged. Actinomorphic Most flowers are actinomorphic ("star shaped", "radial"), meaning they can be divided into three or more identical sectors which are related to each other by rotation about the center of the flower. Typically, each sector might contain one tepal or one petal and one sepal and so on. It may or may not be possible to divide the flower into symmetrical halves by the same number of longitudinal planes passing through the axis: oleander is an example of a flower without such mirror planes. Actinomorphic flowers are also called radially symmetrical or regular flowers. Other examples of actinomorphic flowers are the lily (''Lilium'', Liliaceae) and the buttercup ('' Ranunculus'', Ranunculaceae). Zygomorphic Zy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stigma (botany)
The stigma (: stigmas or stigmata) is the receptive tip of a Gynoecium#Carpels, carpel, or of several fused carpels, in the gynoecium of a flower. Description The stigma, together with the Style (botany), style and ovary (botany), ovary (typically called the stigma-style-ovary system) comprises the pistil, which is part of the gynoecium or female reproductive organ of a plant. The stigma itself forms the distal portion of the style, or stylodia, and is composed of , the cells of which are receptive to pollen. These may be restricted to the apex of the style or, especially in wind pollinated species, cover a wide surface. The stigma receives pollen and it is on the stigma that the pollen grain germination, germinates. Often sticky, the stigma is adapted in various ways to catch and trap pollen with various hairs, flaps, or sculpturings. The pollen may be captured from the air (wind-borne pollen, anemophily), from visiting insects or other animals (Pollination syndrome#Biotic, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petal
Petals are modified leaves that form an inner whorl surrounding the reproductive parts of flowers. They are often brightly coloured or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corolla''. Petals are usually surrounded by an outer whorl of modified leaves called sepals, that collectively form the ''calyx'' and lie just beneath the corolla. The calyx and the corolla together make up the perianth, the non-reproductive portion of a flower. When the petals and sepals of a flower are difficult to distinguish, they are collectively called tepals. Examples of plants in which the term ''tepal'' is appropriate include genera such as '' Aloe'' and '' Tulipa''. Conversely, genera such as '' Rosa'' and '' Phaseolus'' have well-distinguished sepals and petals. When the undifferentiated tepals resemble petals, they are referred to as "petaloid", as in petaloid monocots, orders of monocots with brightly coloured tepals. Since they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Receptacle (botany)
In botany, the receptacle refers to vegetative tissues near the end of reproductive stems that are situated below or encase the reproductive organs. Angiosperms In angiosperms, the receptacle or torus (an older term is thalamus, as in Thalamiflorae) is the thickened part of a stem (pedicel) from which the flower organs grow. In some accessory fruits, for example the pome and strawberry, the receptacle gives rise to the edible part of the fruit. The fruit of ''Rubus'' species is a cluster of drupelets on top of a conical receptacle. When a raspberry is picked, the receptacle separates from the fruit, but in blackberries, it remains attached to the fruit. — In the daisy family (Compositae or Asteraceae), small individual flowers are arranged on a round or dome-like structure that is also called receptacle. Algae and bryophyta In phycology, receptacles occur at the ends of branches of algae mainly in the brown algae Brown algae (: alga) are a large group of multice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bract
In botany, a bract is a modified or specialized leaf, associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves in size, color, shape or texture. They also look different from the parts of the flower, such as the petals or sepals. A plant having bracts is referred to as bracteate or bracteolate, while one that lacks them is referred to as ebracteate or ebracteolate. Variants Some bracts are brightly coloured which aid in the attraction of pollinators, either together with the perianth or instead of it. Examples of this type of bract include those of '' Euphorbia pulcherrima'' (poinsettia) and '' Bougainvillea'': both of these have large colourful bracts surrounding much smaller, less colourful flowers. In grasses, each floret (flower) is enclosed in a pair of papery bracts, called the lemma (lower bract) and palea (upper bract), while each spikelet (group of florets) has a further pair o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gland (botany)
In plants, a gland is defined functionally as a plant structure which secretes one or more products. This may be located on or near the plant surface and secrete externally, or be internal to the plant and secrete into a canal or reservoir. Examples include glandular hairs, nectaries, hydathodes, and the resin canals in Pinus. Notable examples Salt glands of the mangrove The salt glands of mangroves such as '' Acanthus'', '' Aegiceras'', '' Aegialitis'' and ''Avicennia'' are a distinctive multicellular trichome, a glandular hair found on the upper leaf surface and much more densely in the abaxial indumentum. On the upper leaf surface they are sunken in shallow pits, and on the lower surface they occur scattered among long nonglandular hairs composed of three or four cells. Development of the glands resembles that of the nonglandular hairs until the three-celled stage, when the short middle stalk cell appears. The salt gland continues to develop to produce two to four vacu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
