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Bursaphelenchus Xylophilus
''Bursaphelenchus xylophilus'', commonly known as pine wood nematode or pine wilt nematode (PWN), is a species of nematode that infects trees in the ''Pinus'' genus of coniferous trees and causes the disease pine wilt.''Bursaphelenchus xylophilus''. Nemaplex. UC Davis. While native to North America, it spread in the early 20th century to and in the latter half of the century to other areas of , including , |
Spicule (nematode)
In nematodes, spicules, also known as copulatory spicules, are needle-like mating structures found only in males. Male nematodes may have one or two spicules which serve to open the vulva of females and facilitate the transmission of sperm Sperm (: sperm or sperms) is the male reproductive Cell (biology), cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Animals produce motile sperm ..., although sperm is not transferred directly by or through the spicules.Chitwood, B. G. & Chitwood, M. B. (1950). Introduction to Nematology (Vol. 1). Baltimore: Monumental Printing Co. (Function of spicule: pages 123-124) The gubernaculum is another organ of the nematode male copulatory system which guides the spicules during copulation. References Nematode anatomy Animal male reproductive system {{nematode-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pinus Densiflora
''Pinus densiflora'', also called the Japanese red pine, the Japanese pine, or Korean red pine, is a species of pine tree native to East Asia and Siberia. In China, the plant is known as 赤松 (pinyin: chì sōng, literally "red pine"). Distribution and habitat ''P. densiflora'' has a home range that includes Japan, the Korean Peninsula, northeastern China (Heilongjiang, Jilin, Liaoning, Shandong and northeastern Jiangsu) and the extreme southeast of Russia (in Siberia, southern Primorsky Krai). Description The leaves are needle-like, long, with two per fascicle. The short leaves are 5–6 cm. There are stomatal lines on both sides of the leaf, two vascular bundles, about three to nine resin canals, and fine serrations on the edge of the leaf. Branchlets with more or less white powder. Male cones are light reddish yellow, clustered in the lower part of new branches, female cones are light reddish purple, solitary or clustered in two to three clusters. The cones are dark brown ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Restriction Fragment Length Polymorphism
In molecular biology, restriction fragment length polymorphism (RFLP) is a technique that exploits variations in homologous DNA sequences, known as polymorphisms, populations, or species or to pinpoint the locations of genes within a sequence. The term may refer to a polymorphism itself, as detected through the differing locations of restriction enzyme sites, or to a related laboratory technique by which such differences can be illustrated. In RFLP analysis, a DNA sample is digested into fragments by one or more restriction enzymes, and the resulting ''restriction fragments'' are then separated by gel electrophoresis according to their size. RFLP analysis is now largely obsolete due to the emergence of inexpensive DNA sequencing technologies, but it was the first DNA profiling technique inexpensive enough to see widespread application. RFLP analysis was an important early tool in genome mapping, localization of genes for genetic disorders, determination of risk for disease, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morphology (biology)
Morphology (from Ancient Greek μορφή (morphḗ) "form", and λόγος (lógos) "word, study, research") is the study of the form and structure of organisms and their specific structural features. This includes aspects of the outward appearance (shape, structure, color, pattern, size), as well as the form and structure of internal parts like bones and organs, i.e., anatomy. This is in contrast to physiology, which deals primarily with function. Morphology is a branch of life science dealing with the study of the overall structure of an organism or taxon and its component parts. History The etymology of the word "morphology" is from the Ancient Greek (), meaning "form", and (), meaning "word, study, research". While the concept of form in biology, opposed to function, dates back to Aristotle (see Aristotle's biology), the field of morphology was developed by Johann Wolfgang von Goethe (1790) and independently by the German anatomist and physiologist Karl Fried ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bursaphelenchus
__NOTOC__ ''Bursaphelenchus'' is a genus of nematodes (roundworms) in the order Aphelenchida. Most are obligate mycophages, but some feed on wood, with two species, the red ring nematode (''B. cocophilus'') and the pine wood nematode (''B. xylophilus''), economically significant as pests of coconut palms and of pine trees, respectively. Given that ''Bursaphelenchus'' species are usually hard to distinguish from one another except by trained nematologists with access to microscopes or DNA sequence analysis, the entire genus is put under quarantine in some countries. Where this is not the case however, these nematodes are becoming established as model organism A model organism is a non-human species that is extensively studied to understand particular biological phenomena, with the expectation that discoveries made in the model organism will provide insight into the workings of other organisms. Mo ...s for nematode developmental biology, ecology and genetics. As of 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecological Disturbance
In ecology, a disturbance is a change in environmental conditions that causes a pronounced change in an ecosystem. Disturbances often act quickly and with great effect, to alter the physical structure or arrangement of biotic and abiotic elements. A disturbance can also occur over a long period of time and can impact the biodiversity within an ecosystem. Ecological disturbances include fires, flooding, storms, insect outbreaks, trampling, human presence, earthquakes, plant diseases, infestations, volcanic eruptions, impact events, etc. Not only invasive species can have a profound effect on an ecosystem, native species can also cause disturbance by their behavior. Disturbance forces can have profound immediate effects on ecosystems and can, accordingly, greatly alter the natural community’s population size or species richness. Because of these and the impacts on populations, disturbance determines the future shifts in dominance, various species successively becoming domina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Climate Change
Present-day climate change includes both global warming—the ongoing increase in Global surface temperature, global average temperature—and its wider effects on Earth's climate system. Climate variability and change, Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global temperatures is Scientific consensus on climate change, driven by human activities, especially fossil fuel burning since the Industrial Revolution. Fossil fuel use, Deforestation and climate change, deforestation, and some Greenhouse gas emissions from agriculture, agricultural and Environmental impact of concrete, industrial practices release greenhouse gases. These gases greenhouse effect, absorb some of the heat that the Earth Thermal radiation, radiates after it warms from sunlight, warming the lower atmosphere. Carbon dioxide, the primary gas driving global warming, Carbon dioxide in Earth's atmosphere, has increased in concentratio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nigeria
Nigeria, officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf of Guinea in the Atlantic Ocean to the south. It covers an area of . With Demographics of Nigeria, a population of more than 230 million, it is the List of African countries by population, most populous country in Africa, and the List of countries and dependencies by population, world's sixth-most populous country. Nigeria borders Niger in Niger–Nigeria border, the north, Chad in Chad–Nigeria border, the northeast, Cameroon in Cameroon–Nigeria border, the east, and Benin in Benin–Nigeria border, the west. Nigeria is a Federation, federal republic comprising 36 States of Nigeria, states and the Federal Capital Territory, Nigeria, Federal Capital Territory, where its capital, Abuja, is located. The List of Nigerian cities by population, largest city in Nigeria by population is Lagos, one of the largest List of largest cities, metr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mexico
Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundary, maritime boundaries with the Pacific Ocean to the west, the Caribbean Sea to the southeast, and the Gulf of Mexico to the east. Mexico covers 1,972,550 km2 (761,610 sq mi), and is the List of countries by area, thirteenth-largest country in the world by land area. With a population exceeding 130 million, Mexico is the List of countries by population, tenth-most populous country in the world and is home to the Hispanophone#Countries, largest number of native Spanish speakers. Mexico City is the capital and List of cities in Mexico, largest city, which ranks among the List of cities by population, most populous metropolitan areas in the world. Human presence in Mexico dates back to at least 8,000 BC. Mesoamerica, considered a cradle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pinus Pinaster
''Pinus pinaster'', the maritime pine or cluster pine, is a pine native to the south Atlantic Europe region and parts of the western Mediterranean. It is a hard, fast growing pine bearing small seeds with large wings. Description ''Pinus pinaster'' is a medium-size tree, reaching tall with a Trunk (botany), trunk diameter of up to , exceptionally . The Bark (botany), bark is orange-red, thick, and deeply fissured at the base of the trunk, somewhat thinner in the upper Crown (botany), crown. The leaves ('needles') are in pairs, very stout ( broad), up to long, and bluish-green to distinctly yellowish-green. The maritime pine features the longest and most robust needles of all European pine species. The conifer cone, cones are conic, long and broad at the base when closed, green at first, ripening glossy red-brown when 24 months old. They open slowly over the next few years, or after being heated by a wildfire, forest fire, to release the seeds, opening to broad. The seeds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Springer Science+Business Media
Springer Science+Business Media, commonly known as Springer, is a German multinational publishing company of books, e-books and peer-reviewed journals in science, humanities, technical and medical (STM) publishing. Originally founded in 1842 in Berlin, it expanded internationally in the 1960s, and through mergers in the 1990s and a sale to venture capitalists it fused with Wolters Kluwer and eventually became part of Springer Nature in 2015. Springer has major offices in Berlin, Heidelberg, Dordrecht, and New York City. History Julius Springer founded Springer-Verlag in Berlin in 1842 and his son Ferdinand Springer grew it from a small firm of 4 employees into Germany's then second-largest academic publisher with 65 staff in 1872.Chronology ". Springer Science+Business Media. In 1964, Springer expanded its business internationally, op ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chamaecyparis Obtusa
''Chamaecyparis obtusa'' (Japanese cypress, hinoki cypress or hinoki; or , ) is a species of cypress native to central Japan in East Asia, and widely cultivated in the temperate climate, temperate northern hemisphere for its high-quality timber and ornamental qualities, with many cultivars commercially available. Description It is a slow-growing tree which may reach tall with a trunk up to in diameter. The bark is dark red-brown. The leaf, leaves are scale-like, long, blunt tipped (obtuse), green above, and green below with a white stomatal band at the base of each scale-leaf. The conifer cone, cones are globose, in diameter, with 8–12 scales arranged in opposite pairs. Related species The plant is widespread in Japan. The related ''Chamaecyparis pisifera'' (sawara cypress) can be readily distinguished in its having pointed tips to the leaves and smaller cones. A similar cypress found on Taiwan is treated by different botanists as either a variety of this species (as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
