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Rc (gene)
The agricultural weed syndrome is the set of common traits which make a plant a successful agricultural weed. Most of these traits are not, themselves, phenotypes but are instead methods of rapid adaptation. So equipped, plants of various origins - invasives, natives, mildly successful marginal weeds of agriculture, weeds of other settings - accumulate other characteristics which allow them to compete in an environment with a high degree of human management. Nonetheless, some of the syndrome traits are themselves phenotypic. Syndrome traits * Rapid growth * Efficient use of nutrients * Seed dormancy * Effective seed dispersal, often more aggressive shattering * Vavilovian mimicry including introgression of crop alleles if there are nearby crop relatives * Herbicide resistance * Short life cycle * High fertility Some of these are the opposite of domestication traits. Evolution Insufficient information is available as to the exact contribution of mutations, particular mutation typ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weed
A weed is a plant considered undesirable in a particular situation, "a plant in the wrong place", or a plant growing where it is not wanted.Harlan, J. R., & deWet, J. M. (1965). Some thoughts about weeds. ''Economic botany'', ''19''(1), 16-24. This introduces the concept of humans and their goals in a particular setting.Holzner, W., & Numata, M. (Eds.). (2013). ''Biology and ecology of weeds'' (Vol. 2). Springer Science & Business Media. The concept of weeds is particularly significant in agriculture, where the aim is growing crops or pastures of a single species, or a mixture of a few desired species. In such environments, other plant species are considered undesirable and therefore a weed. Besides, some weeds have undesirable characteristics making them a plant pest in most human settings.Harlan, J. R., & deWet, J. M. (1965). Some thoughts about weeds. ''Economic botany'', ''19''(1), 16-24.Holzner, W., & Numata, M. (Eds.). (2013). ''Biology and ecology of weeds'' (Vol. 2). Spri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Domestication Traits
Domestication syndrome refers to two sets of phenotypic traits that are common to either domesticated animals, or domesticated plants. These traits were identified by Charles Darwin in '' The Variation of Animals and Plants Under Domestication.'' Domesticated animals tend to be smaller and less aggressive than their wild counterparts, they may also have floppy ears, variations to coat color, a smaller brain, and a shorter muzzle. Other traits may include changes in the endocrine system and an extended breeding cycle. Research suggests that modified neural crest cells are potentially responsible for the traits that are common across many domesticated animal species. The process of plant domestication has produced changes in shattering/fruit abscission, shorter height, larger grain or fruit size, easier threshing, synchronous flowering, and increased yield, as well as changes in color, taste, and texture. Origin Charles Darwin's study of ''The Variation of Animals and Plant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modes Of Action
A mode of action (MoA) describes a functional or anatomical change, resulting from the exposure of a living organism to a substance. In comparison, a mechanism of action (MOA) describes such changes at the molecular level. A mode of action is important in classifying chemicals, as it represents an intermediate level of complexity in between molecular mechanisms and physiological outcomes, especially when the exact molecular target has not yet been elucidated or is subject to debate. A mechanism of action of a chemical could be "binding to DNA" while its broader mode of action would be "transcriptional regulation". However, there is no clear consensus and the term mode of action is also often used, especially in the study of pesticides, to describe molecular mechanisms such as action on specific nuclear receptors or enzymes. Disinfectants are commonly used in order to eliminate microorganisms. The effectiveness of a disinfectant is dependent on both the chemical composition of the pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echinochloa Oryzicola
''Echinochloa'' is a very widespread genus of plants in the grass family and tribe Paniceae. Some of the species are known by the common names barnyard grass or cockspur grass. Some of the species within this genus are millets that are grown as cereal or fodder crops. The most notable of these are Japanese millet (''E. esculenta'') in East Asia, Indian barnyard millet (''E. frumentacea'') in South Asia, and burgu millet (''E. stagnina'') in West Africa. Collectively, the members of this genus are called barnyard grasses (though this may also refer to '' E. crus-galli'' specifically), and are also known as barnyard millets or billion-dollar grasses. When not grown on purpose, these grasses may become a nuisance to farmers. In particular, common barnyard grass (''E. crus-galli'') is notorious as a weed. It is not easily suppressed with living mulches such as velvet bean (''Mucuna pruriens'' var. ''utilis''). Early barnyard grass (''E. oryzoides'') is a well-known example of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echinochloa Crus-galli
''Echinochloa crus-galli'' is a type of wild grass originating from tropical Asia that was formerly classified as a type of panicum grass. It is commonly known as cockspur (or cockspur grass), barnyard millet, Japanese millet, water grass, common barnyard grass, or simply "barnyard grass" (which may refer to any species of ''Echinochloa'' or the genus as a whole however). This plant can grow to 60" (1.5 m) in height and has long, flat leaves which are often purplish at the base. Most stems are upright, but some will spread out over the ground. Stems are flattened at the base. The seed heads are a distinctive feature, often purplish, with large millet-like seeds in crowded spikelets. Considered one of the world's worst weeds, it reduces crop yields and causes forage crops to fail by removing up to 80% of the available soil nitrogen. It acts as a host for several mosaic virus diseases.Heuzé V., Thiollet H., Tran G., Lebas F., 2017. Cockspur grass (Echinochloa crus-galli) forage. Fe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ipomoea Purpurea
''Ipomoea purpurea'', the common morning-glory, tall morning-glory, or purple morning glory, is a species in the genus ''Ipomoea'', native to Mexico and Central America. Description Like all morning glories, the plant entwines itself around structures, growing to a height of tall. The leaves are heart-shaped and the stems are covered with brown hairs. The flowers are trumpet-shaped, predominantly blue to purple or white, and in diameter. Distribution and habitat The plant is predisposed to moist and rich soil, but can be found growing in a wide array of soil types.Richard H. Uva, Joseph C. Neal and Joseph M. Ditomaso, ''Weeds of The Northeast'', (Ithaca, NY: Cornell University Press, 1997), Pp. 214-217. It is naturalized throughout warm temperate and subtropical regions of the world. Although it is often considered a noxious weed, ''I. purpurea'' is also grown for its attractive purple and white flowers, and has many cultivars. Common cultivars include ''I. purpurea'' 'Crimson ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lolium Rigidum
''Lolium rigidum'' is a species of annual grass. Common names by which it is known include annual ryegrass, a name also given to Italian ryegrass (''Lolium multiflorum''), rigid ryegrass, stiff darnel, Swiss ryegrass and Wimmera ryegrass. It is a native of southern Europe, northern Africa, the Middle East and the Indian subcontinent and is grown as a forage crop, particularly in Australia, where it is also a serious and economically damaging crop weed. Description ''Lolium rigidum'' is an annual grass that grows in open tussocks. It has fibrous roots and can grow up to a metre tall. The plant form is usually erect but may be prostrate. The stems are often geniculate (with a knee-like bend) and are purplish at the base. The leaves are long, and wide; the upper surface is glossy dark green, flat and hairless with longitudinal veins, and the underside is shiny and smooth. The young leaves are rolled when in bud, the auricles are small and the ligule is white and translucent, wide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amaranthus Palmeri
''Amaranthus palmeri'' is a species of edible flowering plant in the amaranth genus. It has several common names, including carelessweed, dioecious amaranth, Palmer's amaranth, Palmer amaranth, and Palmer's pigweed. It is native to most of the southern half of North America. Populations in the eastern United States are probably naturalized. It has also been introduced to Europe, Australia, and other areas. The plant is fast-growing and highly competitive. Uses The leaves, stems and seeds of Palmer amaranth, like those of other amaranths, are edible and highly nutritious. Palmer amaranth was once widely cultivated and eaten by Native Americans across North America, both for its abundant seeds and as a cooked or dried green vegetable. Other related ''Amaranthus'' species have been grown as crops for their greens and seeds for thousands of years in Mexico, South America, the Caribbean, Africa, India, and China. The plant can be toxic to livestock animals due to the presence of nit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amaranthus Tuberculatus
''Amaranthus tuberculatus'', commonly known as roughfruit amaranth, rough-fruited water-hemp, tall waterhemp, or common waterhemp, is a species of flowering plant. It is a summer annual broadleaf with a germination period that lasts several months. Tall waterhemp has been reported as a weed in 40 of 50 U.S. states. Morphology A distinguishing characteristic of tall waterhemp that sets it apart from similar members of the genus Amaranthus is the lack of hair on its stems and leaves. This characteristic gives the plant a bright, glossy appearance. The leaves of tall waterhemp tend to be long and narrow. The stem is typically erect and slender and can be up to three feet long. The color of the stem is green or red. Tall waterhemp is a dioecious plant. The seedhead branches in the female are numerous, short, and smooth. The male seedhead branches are fewer, longer, and more slender than those of the female. The species has terminal spike inflorescences and very short bra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radish
The radish (''Raphanus raphanistrum'' subsp. ''sativus'') is an Eating, edible root vegetable of the family Brassicaceae that was domesticated in Asia prior to Roman Empire, Roman times. Radishes are grown and consumed throughout the world, being mostly eaten raw as a crunchy salad vegetable with a pungency, pungent, slightly spicy flavor, varying in intensity depending on its growing environment. There are numerous variety (botany), varieties, varying in size, flavor, color, and length of time they take to mature. Radishes owe their sharp flavor to the various chemical compounds produced by the plants, including glucosinolate, myrosinase, and isothiocyanate. They are sometimes grown as companion plants and suffer from few pests and diseases. They germinate quickly and grow rapidly, common smaller varieties being ready for consumption within a month, while larger ''daikon'' varieties take several months. Being easy to grow and quick to harvest, radishes are often planted by novi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raphanus Raphanistrum
''Raphanus raphanistrum'', also known as wild radish, white charlock or jointed charlock, is a flowering plant in the family Brassicaceae. One of its subspecies, ''Raphanus raphanistrum'' subsp. ''sativus'', includes a diverse variety of cultivated radishes. The species is native to western Asia, Europe and parts of Northern Africa. It has been introduced into most parts of the world and is regarded as a habitat threatening invasive species in many areas, for example, Australia. It spreads rapidly and is often found growing on roadsides or in other places where the ground has been disturbed. Description Wild radish is an annual that grows up to 75 cm tall, variously branched to multi-stemmed, with a distinct slender taproot which does not swell like that of the cultivated radish. The stems are green and sometimes purple at the base and nodes, round in cross section and slightly ridged, and bristly-hairy all over. It has a basal rosette of pinnate leaves to 38 cm long, with a 3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Introgression
Introgression, also known as introgressive hybridization, in genetics is the transfer of genetic material from one species into the gene pool of another by the repeated backcrossing of an interspecific hybrid with one of its parent species. Introgression is a long-term process, even when artificial; it may take many hybrid generations before significant backcrossing occurs. This process is distinct from most forms of gene flow in that it occurs between two populations of different species, rather than two populations of the same species. Introgression also differs from simple hybridization. Simple hybridization results in a relatively even mixture; gene and allele frequencies in the first generation will be a uniform mix of two parental species, such as that observed in mules. Introgression, on the other hand, results in a complex, highly variable mixture of genes, and may only involve a minimal percentage of the donor genome. Definition Introgression or introgressive hybri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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