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Phytophthora Cinnamomi
''Phytophthora cinnamomi'' is a soil-borne water mould that produces an infection which causes a condition in plants variously called "root rot", "dieback", or (in certain '' Castanea'' species), "ink disease". The plant pathogen is one of the world's most invasive species and is present in over 70 countries around the world. Host range and symptoms The host range for ''Phytophythora cinnamomi'' is very broad. It is distributed worldwide and causes disease on hundreds of hosts. The disease affects a range of economic groups, including food crops such as avocado and pineapple as well as trees and woody ornamentals such as Fraser firs, shortleaf pines, loblolly pines, azaleas, camellia, boxwood, causing root rot and dieback. It is a root pathogen that causes root rot and death of host plants. Some symptoms include: wilting, decreased fruit size, decrease in yield, collar rot, gum exudation, necrosis, leaf chlorosis, leaf curl, and stem cankers. Another symptom is that it can cause ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert Delafield Rands
Robert Delafield Rands (1890–1970) was an American agronomist and mycologist. He served as Chief Director of Agriculture Office of Rubber Plant Investigations in the United States Department of Agriculture. Biography Rands was born in 1890. His Ph.D thesis at the University of Wisconsin was in the field of plant pathology. In research in Indonesia, he showed that "brown bast" in ''Hevea'' species was a result of phloem necrosis due to tapping of the trees for latex. Rands met Minnie Frost, then a graduate student at the University of Chicago, in a field trip to the Rocky Mountains of Colorado. A year later they married in Frost's home town of Louisville, Kentucky on December 25, 1914. Minnie Frost Rands wrote a book about her experiences in the places the couple traveled to. After returning to the United States, Rands worked for the United States Department of Agriculture into diseases of sugar cane, and then at the beginning of World War II returned to study of rubber plants. H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoospore
A zoospore is a motile asexual spore that uses a flagellum for locomotion. Also called a swarm spore, these spores are created by some protists, bacteria, and fungi to propagate themselves. Diversity Flagella types Zoospores may possess one or more distinct types of flagella - tinsel or "decorated", and whiplash, in various combinations. *Tinsellated (straminipilous) flagella have lateral filaments known as mastigonemes perpendicular to their main axis, which allow for more surface area, and disturbance of the medium, giving them the property of a rudder, that is, used for steering. *Whiplash flagella are straight, to power the zoospore through its medium. Also, the "default" zoospore only has the propelling, whiplash flagella. Both tinsel and whiplash flagella beat in a sinusoidal wave pattern, but when both are present, the tinsel beats in the opposite direction of the whiplash, to give two axes of control of motility. Morphological types In eukaryotes, the four main types ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Die Back Valley Gnangarra
Die, as a verb, refers to death, the cessation of life. Die may also refer to: Games * Die, singular of dice, small throwable objects used for producing random numbers Manufacturing * Die (integrated circuit), a rectangular piece of a semiconductor wafer * Die (manufacturing), a material-shaping device * Die (philately) * Coin die, a metallic piece used to strike a coin * Die casting, a material-shaping process ** Sort (typesetting), a cast die for printing * Die cutting (web), process of using a die to shear webs of low-strength materials * Die, a tool used in paper embossing * Tap and die, cutting tools used to create screw threads in solid substances * Tool and die, the occupation of making dies Arts and media Music * ''Die'' (album), the seventh studio album by rapper Necro * Die (musician), Japanese musician, guitarist of the band Dir en grey * DJ Die, British DJ and musician with Reprazent * "DiE", a 2013 single by the Japanese idol group BiS * die!, an inactive German ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Texas
Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2020, it is the second-largest U.S. state by both List of U.S. states and territories by area, area (after Alaska) and List of U.S. states and territories by population, population (after California). Texas shares borders with the states of Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the west, and the Mexico, Mexican States of Mexico, states of Chihuahua (state), Chihuahua, Coahuila, Nuevo León, and Tamaulipas to the south and southwest; and has a coastline with the Gulf of Mexico to the southeast. Houston is the List of cities in Texas by population, most populous city in Texas and the List of United States cities by population, fourth-largest in the U.S., while San Antonio is the second most pop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Carolina
)''Animis opibusque parati'' ( for, , Latin, Prepared in mind and resources, links=no) , anthem = " Carolina";" South Carolina On My Mind" , Former = Province of South Carolina , seat = Columbia , LargestCity = Charleston , LargestMetro = Greenville (combined and metro) Columbia (urban) , BorderingStates = Georgia, North Carolina , OfficialLang = English , population_demonym = South Carolinian , Governor = , Lieutenant Governor = , Legislature = General Assembly , Upperhouse = Senate , Lowerhouse = House of Representatives , Judiciary = South Carolina Supreme Court , Senators = , Representative = 6 Republicans1 Democrat , postal_code = SC , TradAbbreviation = S.C. , area_rank = 40th , area_total_sq_mi = 32,020 , area_total_km2 = 82,932 , area_land_sq_mi = 30,109 , area_land_km2 = 77,982 , area_water_sq_mi = 1,911 , area_water_km2 = 4,949 , area_water_percent = 6 , population_rank = 23rd , population_as_of = 2022 , 2010Pop = 5282634 , population ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Chestnut
The American chestnut (''Castanea dentata'') is a large, fast-growing deciduous tree of the beech family native to eastern North America. As is true of all species in genus Castanea, the American chestnut produces burred fruit with edible nuts. The American chestnut was one of the most important forest trees throughout its range and was considered the finest chestnut tree in the world.Davis, Donald E"Historical Significance of American Chestnut on Appalachian Culture and Ecology" ''www.ecosystem.psu.edu'', 2005. Retrieved October 28, 2015. During the early to mid 20th century, American chestnut trees were devastated by chestnut blight, a fungal disease that came from Chinese chestnut trees that were introduced into North America from East Asia. It is estimated that the blight killed between 3 and 4 billion American chestnut trees in the first half of the 20th century, beginning in 1904.Griffin, Gary"Recent advances in research and management of chestnut blight on American chest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territories, nine Minor Outlying Islands, and 326 Indian reservations. The United States is also in free association with three Pacific Island sovereign states: the Federated States of Micronesia, the Marshall Islands, and the Republic of Palau. It is the world's third-largest country by both land and total area. It shares land borders with Canada to its north and with Mexico to its south and has maritime borders with the Bahamas, Cuba, Russia, and other nations. With a population of over 333 million, it is the most populous country in the Americas and the third most populous in the world. The national capital of the United States is Washington, D.C. and its most populous city and principal financial center is New York City. Paleo-Americ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homothallism
Homothallic refers to the possession, within a single organism, of the resources to reproduce sexually; i.e., having male and female reproductive structures on the same thallus. The opposite sexual functions are performed by different cells of a single mycelium. It can be contrasted to heterothallic. It is often used to categorize fungi. In yeast, heterothallic cells have mating types a and α. An experienced mother cell (one that has divided at least once) will switch mating type every cell division cycle because of the ''HO'' allele. Sexual reproduction commonly occurs in two fundamentally different ways in fungi. These are outcrossing (in heterothallic fungi) in which two different individuals contribute nuclei to form a zygote, and self-fertilization or selfing (in homothallic fungi) in which both nuclei are derived from the same individual. Homothallism in fungi can be defined as the capability of an individual spore to produce a sexually reproducing colony when propagated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oospore
An oospore is a thick-walled sexual spore that develops from a fertilized oosphere in some algae, fungi, and oomycetes. They are believed to have evolved either through the fusion of two species or the chemically-induced stimulation of mycelia, leading to oospore formation. In Oomycetes, oospores can also result from asexual reproduction, by apomixis In botany, apomixis is asexual reproduction without fertilization. Its etymology is Greek for "away from" + "mixing". This definition notably does not mention meiosis. Thus "normal asexual reproduction" of plants, such as propagation from cuttin .... These are found in fungi as sexual spores which help the sexual reproduction of fungi. These haploid, non-motile spores are the site of meiosis and karyogamy in oomycetes. A dormant oospore, when observed under an electron microscope, has led researchers to draw conclusion that there is only a single central globule with other storage bodies surrounding it. References Reproducti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gametangium
A gametangium (plural: gametangia) is an organ or cell in which gametes are produced that is found in many multicellular protists, algae, fungi, and the gametophytes of plants. In contrast to gametogenesis in animals, a gametangium is a haploid structure and formation of gametes does not involve meiosis. Types of gametangia Depending on the type of gamete produced in a gametangium, several types can be distinguished. Female Female gametangia are most commonly called archegonia. They produce egg cells and are the sites for fertilization. Archegonia are common in algae and primitive plants as well as gymnosperms. In flowering plants, they are replaced by the embryo sac inside the ovule. Male The male gametangia are most commonly called antheridia. They produce sperm cells that they release for fertilization. Antheridia producing non-motile sperm (spermatia) are called spermatangia. Some antheridia do not release their sperm. For example, the oomycete antheridium is a syncytium w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterothallic
Heterothallic species have sexes that reside in different individuals. The term is applied particularly to distinguish heterothallic fungi, which require two compatible partners to produce sexual spores, from homothallic ones, which are capable of sexual reproduction from a single organism. In heterothallic fungi, two different individuals contribute nuclei to form a zygote. Examples of heterothallism are included for ''Saccharomyces cerevisiae, Aspergillus fumigatus, Aspergillus flavus'', ''Penicillium marneffei'' and ''Neurospora crassa''. The heterothallic life cycle of ''N. crassa'' is given in some detail, since similar life cycles are present in other heterothallic fungi. Life cycle of ''Saccharomyces cerevisiae'' The yeast ''Saccharomyces cerevisiae'' is heterothallic. This means that each yeast cell is of a certain mating type and can only mate with a cell of the other mating type. During vegetative growth that ordinarily occurs when nutrients are abundant, ''S. cerev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ploidy
Ploidy () is the number of complete sets of chromosomes in a cell (biology), cell, and hence the number of possible alleles for Autosome, autosomal and Pseudoautosomal region, pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respectively, in each homologous chromosome pair, which chromosomes naturally exist as. Somatic cells, Tissue (biology), tissues, and Individual#Biology, individual organisms can be described according to the number of sets of chromosomes present (the "ploidy level"): monoploid (1 set), diploid (2 sets), triploid (3 sets), tetraploid (4 sets), pentaploid (5 sets), hexaploid (6 sets), heptaploid or septaploid (7 sets), etc. The generic term polyploidy, polyploid is often used to describe cells with three or more chromosome sets. Virtually all sexual reproduction, sexually reproducing organisms are made up of somatic cells that are diploid or greater, but ploidy level may vary widely between different or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
