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Populus × Canescens
''Populus'' × ''canescens'', the grey poplar, is a hybrid between ''Populus alba'' (white poplar) and '' P. tremula'' (common aspen). It is intermediate between its parents, with a thin grey downy coating on the leaves, which are much less deeply lobed than the leaves of ''P. alba''. It is a very vigorous tree with marked hybrid vigour, reaching tall and with a trunk diameter over much larger than either of its parents. Most trees in cultivation are male, but female trees occur naturally and some of these are also propagated. Taxonomy In 1789 William Aiton described the grey poplar as a variety of ''Populus alba ''Populus alba'', commonly called silver poplar,Webb, C. J.; Sykes, W. R.; Garnock-Jones, P. J. 1988: Flora of New Zealand. Vol. IV. Naturalised Pteridophytes, Gymnosperms, Dicotyledons. 4. Christchurch, New Zealand, Botany Division, D.S.I.R. si ...'', ''P. alba'' var. ''canescens''. In 1804, James Edward Smith raised it to a full species, ''P.&nb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybrid (biology)
In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different varieties, subspecies, species or genera through sexual reproduction. Generally, it means that each cell has genetic material from two different organisms, whereas an individual where some cells are derived from a different organism is called a chimera. Hybrids are not always intermediates between their parents such as in blending inheritance (a now discredited theory in modern genetics by particulate inheritance), but can show hybrid vigor, sometimes growing larger or taller than either parent. The concept of a hybrid is interpreted differently in animal and plant breeding, where there is interest in the individual parentage. In genetics, attention is focused on the numbers of chromosomes. In taxonomy, a key question is how closely related the parent species are. Species are reproductively isolated by strong barriers to hybridization, which include genetic and morph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Populus Alba
''Populus alba'', commonly called silver poplar,Webb, C. J.; Sykes, W. R.; Garnock-Jones, P. J. 1988: Flora of New Zealand. Vol. IV. Naturalised Pteridophytes, Gymnosperms, Dicotyledons. 4. Christchurch, New Zealand, Botany Division, D.S.I.R. silverleaf poplar, white poplar, or abele is a species of Populus, poplar, most closely related to the aspens (''Populus'' sect. ''Populus''). It is native to a region spanning from the Atlas Mountains of Africa, through most of South and Central Europe, into Central Asia; it has been introduced to many temperate, moist regions worldwide. It grows in moist sites, often by watersides, in regions with hot summers and cold to mild winters.Flora Europaea''Populus alba''/ref>Rushforth, K. (1999). ''Trees of Britain and Europe''. Collins . Description It is a medium-sized deciduous tree, growing to heights of up to (rarely more), with a trunk up to in diameter and a broad, rounded crown. The Bark (botany), bark is smooth and greenish-white to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Populus Tremula
''Populus tremula'' (commonly called aspen, common aspen, Eurasian aspen, European aspen, or quaking aspen) is a species of poplar native to cool temperate regions of the Old World. Description It is a substantial deciduous tree growing to tall by broad, with a trunk attaining over in diameter. The bark is pale greenish-grey and smooth on young trees with dark grey diamond-shaped lenticels, becoming dark grey and fissured on older trees. The adult leaves, produced on branches of mature trees, are nearly round, slightly wider than long, diameter, with a coarsely toothed margin and a laterally flattened petiole long. The flat petiole allows them to tremble in even slight breezes, and is the source of its scientific name, as well as one of its vernacular names "langues de femmes" attributed to Gerard's 17th-century ''Herball''. The leaves on seedlings and fast-growing stems of suckers (root sprouts) are of a different shape, heart-shaped to nearly triangular. They are al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leaves
A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, flower, and fruit collectively form the shoot system. In most leaves, the primary photosynthetic tissue is the palisade mesophyll and is located on the upper side of the blade or lamina of the leaf, but in some species, including the mature foliage of ''Eucalyptus'', palisade mesophyll is present on both sides and the leaves are said to be isobilateral. The leaf is an integral part of the stem system, and most leaves are flattened and have distinct upper ( adaxial) and lower ( abaxial) surfaces that differ in color, hairiness, the number of stomata (pores that intake and output gases), the amount and structure of epicuticular wax, and other features. Leaves are mostly green in color due to the presence of a compound called chlorop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterosis
Heterosis, hybrid vigor, or outbreeding enhancement is the improved or increased function of any biological quality in a hybrid offspring. An offspring is heterotic if its traits are enhanced as a result of mixing the genetic contributions of its parents. The heterotic offspring often has traits that are more than the simple addition of the parents' traits, and can be explained by Mendelian or non-Mendelian inheritance. Typical heterotic/hybrid traits of interest in agriculture are higher yield, quicker maturity, stability, drought tolerance etc. Definitions In proposing the term heterosis to replace the older term heterozygosis, G.H. Shull aimed to avoid limiting the term to the effects that can be explained by heterozygosity in Mendelian inheritance. Heterosis is often discussed as the opposite of inbreeding depression, although differences in these two concepts can be seen in evolutionary considerations such as the role of genetic variation or the effects of genetic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horticulture
Horticulture (from ) is the art and science of growing fruits, vegetables, flowers, trees, shrubs and ornamental plants. Horticulture is commonly associated with the more professional and technical aspects of plant cultivation on a smaller and more controlled scale than agronomy. There are various divisions of horticulture because plants are grown for a variety of purposes. These divisions include, but are not limited to: propagation, arboriculture, landscaping, floriculture and turf maintenance. For each of these, there are various professions, aspects, tools used and associated challenges -- each requiring highly specialized skills and knowledge on the part of the horticulturist. Typically, horticulture is characterized as the ornamental, small-scale and non-industrial cultivation of plants; horticulture is distinct from gardening by its emphasis on scientific methods, plant breeding, and technical cultivation practices, while gardening, even at a professional level, tends ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Aiton
William Aiton (17312 February 1793) was a Scotland, Scottish botanist. Aiton was born near Hamilton, Scotland, Hamilton. Having been regularly trained to the profession of a gardener, he travelled to London in 1754, and became assistant to Philip Miller, then superintendent of the Chelsea Physic Garden. In 1759 he was appointed director of the newly established Royal Botanic Gardens, Kew, botanical garden at Kew, where he remained until his death. He effected many improvements at the gardens, and in 1789 he published ''Hortus Kewensis'', a catalogue of the plants cultivated there. He is buried at nearby St. Anne's Church, Kew. A second and enlarged edition of the ''Hortus'' was brought out in 1810–1813 by his eldest son, William Townsend Aiton. Aiton is commemorated in the Specific epithet (botany), specific epithet ''aitonis''. In 1789, he classified the Sampaguita plant to the ''Jasmine, Jasminium'' genus and also named it as ''Arabian Jasmine'' because it was believed th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variety (botany)
In botanical nomenclature, variety (abbreviated var.; in ) is a taxonomic rank below that of species and subspecies, but above that of form. As such, it gets a three-part infraspecific name. It is sometimes recommended that the subspecies rank should be used to recognize geographic distinctiveness, whereas the variety rank is appropriate if the taxon is seen throughout the geographic range of the species. Example The pincushion cactus, ''Escobaria vivipara'', is a wide-ranging variable species occurring from Canada to Mexico, and found throughout New Mexico below about . Nine varieties have been described. Where the varieties of the pincushion cactus meet, they intergrade. The variety ''Escobaria vivipara'' var. ''arizonica'' is from Arizona, while ''Escobaria vivipara'' var. ''neo-mexicana'' is from New Mexico. Definitions The term is defined in different ways by different authors. However, the International Code of Nomenclature for Cultivated Plants, while recognizing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Edward Smith (botanist)
Sir James Edward Smith (2 December 1759 – 17 March 1828) was an English botanist and founder of the Linnean Society. Early life and education Smith was born in Norwich in 1759, the son of a wealthy wool merchant. He started studying botanical science when he was eighteen. In 1781 he enrolled in the medical course at the University of Edinburgh, where he studied chemistry under Joseph Black, natural history under John Walker, and botany under John Hope, an early teacher of Linnaean taxonomy. He moved to London in 1783 to continue his studies and became a friend of Sir Joseph Banks, who was offered the entire collection of books, manuscripts and specimens of the Swedish natural historian and botanist Carl Linnaeus following the death of his son Carolus Linnaeus the Younger. Banks declined the purchase, but Smith borrowed money from his father and bought the collection for the price of £1,000 in 1784. Smith was elected a Fellow of the Royal Society in 1785. Academic ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Populus
''Populus'' is a genus of 25–30 species of deciduous flowering plants in the family Salicaceae, native to most of the Northern Hemisphere. English names variously applied to different species include poplar (), aspen, and cottonwood. The western balsam poplar (Populus trichocarpa, ''P. trichocarpa'') was the first tree to have its full DNA code determined by DNA sequencing, in 2006. Description The genus has a large genetic diversity, and can grow from tall, with trunks up to in diameter. The Bark (botany), bark on young trees is smooth and white to greenish or dark gray, and often has conspicuous lenticels; on old trees, it remains smooth in some species, but becomes rough and deeply fissured in others. The shoots are stout, with (unlike in the related willows) the terminal bud present. The leaves are spirally arranged, and vary in shape from triangular to circular or (rarely) lobed, and with a long petiole (botany), petiole; in species in the sections ''Populus'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
