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Gymnarrhena
''Gymnarrhena'' is a deviant genus of plants in the family Asteraceae, with only one known species, ''Gymnarrhena micrantha''. It is native to North Africa and the Middle East, as far east as Balochistan. Together with the very different '' Cavea tanguensis'' it constitutes the tribe Gymnarrheneae, and in the subfamily Gymnarrhenoideae. ''Gymnarrhena'' is a small, flowering, winter annual with a rosette of simple, narrow leaves and flower heads cropped at its hart. It does not contain latex and does not carry spines. ''Gymnarrhena'' flowers in March and April. One of the common names in Arabic is كَف الكَلْب meaning "dog's footprint", while in Hebrew it is called מוצנית קטנת-פרחים meaning "small chaff flower". Description ''Gymnarrhena micrantha'' is a dwarf annual herb of ½–2½ cm high, with all its leaves in rosette of up to 10 cm in diameter, and its flowers tucked away in the hart of this rosette, that is lacking latex, and does not ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gymnarrhena Micrantha003
''Gymnarrhena'' is a deviant genus of plants in the family Asteraceae, with only one known species, ''Gymnarrhena micrantha''. It is native to North Africa and the Middle East, as far east as Balochistan. Together with the very different ''Cavea tanguensis'' it constitutes the tribe Gymnarrheneae, and in the subfamily Gymnarrhenoideae. ''Gymnarrhena'' is a small, flowering, winter annual with a rosette of simple, narrow leaves and flower heads cropped at its hart. It does not contain latex and does not carry spines. ''Gymnarrhena'' flowers in March and April. One of the common names in Arabic is كَف الكَلْب meaning "dog's footprint", while in Hebrew it is called מוצנית קטנת-פרחים meaning "small chaff flower". Description ''Gymnarrhena micrantha'' is a dwarf annual herb of ½–2½ cm high, with all its leaves in rosette of up to 10 cm in diameter, and its flowers tucked away in the hart of this rosette, that is lacking latex, and does not hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gymnarrhenoideae
Gymnarrhenoideae is a subfamily with in the family Asteraceae, with only one tribe, the Gymnarrheneae. Two very different species have been assigned to it, '' Gymnarrhena micrantha'', a winter annual from the deserts of North-Africa and the Middle-East, and '' Cavea tanguensis'', a perennial herb that grows on scree near streams and glaciers in the Eastern Himalayas. These species have very little in common, other than having two types of flower heads and sharing a tendency towards dioecism. Both also have basal leaf rosettes, stretched leaves, with few spaced teeth on the margin, and both lack spines and latex. Taxonomy The subfamily Gymnarrhenoideae and tribe Gymnarrheneae were erected in 2009 by Jose Panero and Vicki Funk to accommodate the isolated position of ''Gymnarrhena'' that is suggested by genetic analyses. A later analysis including rare species from China illustrated that ''Cavea'' is its sister taxon. Phylogeny Based on recent genetic analysis, it is now genera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cavea Tanguensis
''Cavea'' is a low perennial herbaceous plant that is assigned to the family Asteraceae. ''Cavea tanguensis'' is currently the only species assigned to this genus. It has a basal rosette of entire, slightly leathery leaves, and stems of 5–25 cm high, topped by bowl-shaped flower heads with many slender florets with long pappus and purplish corollas. The vernacular name in Chinese is 葶菊 (ting ju). It grows high in the mountains of China (Sichuan), Tibet, India (Sikkim), and Bhutan, and flowers in July and August. Description ''Cavea'' is a perennial herb with stout, woody and mostly branched rootstocks of 10–30 cm long, which carry a basal leaf rosette and unbranching stems that carry some smaller leaves, bracts and flower heads. Stems and leaves The erect unbranching stems are stout and 5–25 cm high. The leaves in the basal rosette are somewhat leathery or even fleshy, the underside with many or few brownish glandular hairs, elongated spoon-shaped, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hecastocleis
''Hecastocleis'' is a genus of low thorny shrubs with stiff branches, assigned to the daisy family. At the tip of each of the branches, inflorescences are subtended by oval, thorny, whitish to greenish bracts that enclose several flower heads which each contain only one pinkish bud, opening into a white corolla. It contains but one species, ''Hecastocleis shockleyi'', the only representative of the tribe Hecastocleideae, and of the subfamily Hecastocleidoideae. Its vernacular name is prickleleaf. It is confined to the southwestern United States. and Description ''Hecastocleis shockleyi'' is a xerophytic thorny shrub of , occasionally 1½ m (4 ft 11 in) high. It has sixteen chromosomes (2n=16). Leaves The leaves are alternately set along the branches. The leaf blades are hairless or with a few soft hairs, slightly olive green, stiff and leathery, with three main veins, linear to narrowly ovate in shape, long, their base approximately clasping the branch, with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asteraceae
The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae were first described in the year 1740. 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. Most species of Asteraceae are annual, biennial, or perennial herbaceous plants, 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. The primary common characteristic is the existence of sometimes hundreds of tiny individual florets which are held together by protective involucres in flower heads, or more technicall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dioecious
Dioecy (; ; adj. dioecious , ) is a characteristic of a species, meaning that it has distinct individual organisms (unisexual) that produce male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproduction is biparental reproduction. Dioecy has costs, since only about half the population directly produces offspring. It is one method for excluding self-fertilization and promoting allogamy (outcrossing), and thus tends to reduce the expression of recessive deleterious mutations present in a population. Plants have several other methods of preventing self-fertilization including, for example, dichogamy, herkogamy, and self-incompatibility. Dioecy is a dimorphic sexual system, alongside gynodioecy and androdioecy. In zoology In zoology, dioecious species may be opposed to hermaphroditic species, meaning that an individual is either male or female, in which case the synonym gonochory is more often used. Most animal species are dioecious (gon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stamen
The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ 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 and are attached to the filament either at the base or in the middle area of the anther. The sterile tissue between the lobes is called the 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 stamens in a flower are collectively called the androecium. The androecium can consist of as few as one-half stamen (i.e. a single locule) as in ''Canna (plant), Canna'' species or as many as 3,482 stamens which have been counted in the saguaro (''Carnegiea gigantea'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollen
Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophytes during the process of their movement from the stamens to the pistil of flowering plants, or from the male cone to the female cone of gymnosperms. If pollen lands on a compatible pistil or female cone, it germinates, producing a pollen tube that transfers the sperm to the ovule containing the female gametophyte. Individual pollen grains are small enough to require magnification to see detail. The study of pollen is called palynology and is highly useful in paleoecology, paleontology, archaeology, and forensics. Pollen in plants is used for transferring haploid male genetic material from the anther of a single flower to the stigma of another in cross-pollination. In a case of self-pollination, this process takes place from the anth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tricolpate
The eudicots, Eudicotidae, or eudicotyledons are a clade of flowering plants mainly characterized by having two seed leaves upon germination. The term derives from Dicotyledons. Traditionally they were called tricolpates or non-magnoliid dicots by previous authors. The botanical terms were introduced in 1991 by evolutionary botanist James A. Doyle and paleobotanist Carol L. Hotton to emphasize the later evolutionary divergence of tricolpate dicots from earlier, less specialized, dicots. Numerous familiar plants are eudicots, including many common food plants, trees, and ornamentals. Some common and familiar eudicots include sunflower, dandelion, forget-me-not, cabbage, apple, buttercup, maple, and macadamia. Most leafy trees of midlatitudes also belong to eudicots, with notable exceptions being magnolias and tulip trees which belong to magnoliids, and ''Ginkgo biloba'', which is not an angiosperm. Description The close relationships among flowering plants with tricolpa ... [...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 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 wikt:circumscissile, 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 wikt:caducous, caducous. Association with crop breeding Manipulation of dehiscence can improve crop yield since a Trait (biological), trait that causes seed dispersal i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corymbium
''Corymbium'' is a genus of flowering plants in the daisy family comprising nine species. It is the only genus in the subfamily Corymbioideae and the tribe Corymbieae. The species have leaves with parallel veins, strongly reminiscent of monocots, in a rosette and compounded inflorescences may be compact or loosely composed racemes, panicles or corymbs. Remarkable for species in the daisy family, each flower head contains just one, bisexual, mauve, pink or white disc floret within a sheath consisting of just two large involucral bracts. The species are all endemic to the Cape Floristic Region of South Africa, where they are known as plampers. Description The species of ''Corymbium'' are monoecious, stemless, perennial, herbaceous plants of high, that grow in tufts and look like a monocotyledon as long as they are not flowering. The plants have a fibrous rhizome that is covered the persisting bases of old leaves and long, soft, silky hairs. Most parts of the plants may be cov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gundelia
''Gundelia'' is a low to high (20–100 cm) thistle-like perennial herbaceous plant with latex, spiny compound inflorescences, reminiscent of teasles and eryngos, that contain cream, yellow, greenish, pink, purple or redish-purple disk florets. It is assigned to the family Asteraceae. Flowers can be found from February to May. The stems of this plant dry-out when the seeds are ripe and break free from the underground root, and are then blown away like a tumbleweed, thus spreading the seeds effectively over large areas with little standing vegetation. This plant is native to the eastern Mediterranean and the Middle-East. Opinions differ about the number of species in ''Gundelia''. Sometimes the genus is regarded monotypic, ''Gundelia tournefortii'' being a species with a large variability, but other authors distinguish up to nine species, differing in floret color and pubescence. Young stems are cooked and eaten in the Middle-East and are said to taste like a combination of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
