76-639: The Borlaug Global Rust Initiative (BGRI - originally named the Global Rust Initiative) was founded in response to recommendations of a committee of international experts who met to consider a response to the threat the global food supply posed by the Ug99 strain of wheat rust . The BGRI was renamed the Borlaug Global Rust initiative in honor of Green Revolution pioneer and Nobel Peace Prize Laureate Dr. Norman Borlaug who worked to establish and lead
152-550: A writing system , built huge pyramids and temples , had a complex calendar , and developed the concept of zero around 400 CE. The first recorded European references to North America are in Norse sagas where it is referred to as Vinland . The earliest verifiable instance of pre-Columbian trans-oceanic contact by any European culture with the North America mainland has been dated to around 1000 CE. The site , situated at
228-565: A common ancestor, but differ in their virulence /avirulence profiles and the countries in which they have been detected. Ug99 is the product of a type of somatic nuclear exchange event which has not been observed in other stem rust races. During this event and thereafter the nuclei have not experienced recombination . Ug99 and its variants differ from other strains of the Black Stem Rust (BSR) pathogen due to their ability to overcome resistance genes in wheat that have been durable against
304-820: A common ancestor. Also known as PTKS . The first Ug99 race to be characterised. Like most Ug99 races, and unlike other stem rust varieties, it is virulent against the Sr gene Sr31 ; also virulent against Sr38 . Avirulent against Sr24 . It was found in Uganda in 1999 , Kenya in 2001 , Ethiopia in 2003 , Sudan and Yemen in 2006 , Iran in 2007 , and Tanzania in 2009 , Eritrea in 2012 , and Rwanda and Egypt in 2014 . First detected in South Africa in 2000 , Zimbabwe 2009 , and Uganda in 2012 . Avirulent on Sr31 . Discovered in Kenya in 2006
380-512: A continuous process of development of new resistant cultivars and failure of those cultivars. This demonstrates the need for continuous improvement. As of 2020 modern molecular and molecular genetics techniques are identifying quantitative trait loci (QTLs), particular cellular structures, and individual R genes more efficiently than ever before. These will be needed given the continuing severe, worldwide threat Ug99 poses. Sr35 confers resistance to all other severe Pgt races and
456-578: A part of Denmark) and Mexico classified as Latin American). It is unknown with certainty how and when first human populations first reached North America. People were known to live in the Americas at least 20,000 years ago, but various evidence points to possibly earlier dates. The Paleo-Indian period in North America followed the Last Glacial Period, and lasted until about 10,000 years ago when
532-648: A period of mountain building called the Laramide orogeny , between 80 and 55 mya. The formation of the Isthmus of Panama that connected the continent to South America arguably occurred approximately 12 to 15 mya, and the Great Lakes (as well as many other northern freshwater lakes and rivers) were carved by receding glaciers about 10,000 years ago. North America is the source of much of what humanity knows about geologic time periods. The geographic area that would later become
608-571: A powerful earthquake killed seven people in 2009. Volcanic eruptions are common in the region. In 1968, the Arenal Volcano , in Costa Rica, erupted and killed 87 people. Fertile soils from weathered volcanic lavas have made it possible to sustain dense populations in agriculturally productive highland areas. Central America has many mountain ranges ; the longest are the Sierra Madre de Chiapas ,
684-497: A small number of spring wheat land races from North America – 23 out of 250 races with adult plant resistance , 27 out of 23,976 SNPs conveying APR, and only 9 races having seedling resistance . This resistance was present without the Ug99 pathogen challenge being present in NA to drive its selection . USDA has studied winter wheat land races where resistance is more probable. In addition to
760-540: A variety of reactions, including curiosity, trading, cooperation, resignation, and resistance. The indigenous population declined substantially following European arrival, primarily due to the introduction of Eurasian diseases, such as smallpox , to which the indigenous peoples lacked immunity, and because of violent conflicts with Europeans. Indigenous culture changed significantly and their affiliation with political and cultural groups also changed. Several linguistic groups died out , and others changed quite quickly. On
836-841: Is a continent in the Northern and Western Hemispheres . North America is bordered to the north by the Arctic Ocean , to the east by the Atlantic Ocean , to the southeast by South America and the Caribbean Sea , and to the west and south by the Pacific Ocean . The region includes the Bahamas , Bermuda , Canada , the Caribbean , Central America , Clipperton Island , Greenland , Mexico , Saint Pierre and Miquelon , Turks and Caicos Islands , and
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#1733115419033912-533: Is a lineage of wheat stem rust ( Puccinia graminis f. sp. tritici ), which is present in wheat fields in several countries in Africa and the Middle East and is predicted to spread rapidly through these regions and possibly further afield, potentially causing a wheat production disaster that would affect food security worldwide. In 2005 the noted green revolution pioneer Norman Borlaug brought great attention to
988-640: Is a very large continent that extends from north of the Arctic Circle to south of the Tropic of Cancer . Greenland, along with the Canadian Shield , is tundra with average temperatures ranging from 10 to 20 °C (50 to 68 °F), but central Greenland is composed of a very large ice sheet. This tundra radiates throughout Canada, but its border ends near the Rocky Mountains (but still contains Alaska) and at
1064-511: Is an ancient craton which forms the geologic core of North America; it formed between 1.5 and 1.0 billion years ago during the Proterozoic eon. The Canadian Shield is the largest exposure of this craton. From the Late Paleozoic to Early Mesozoic eras, North America was joined with the other modern-day continents as part of the supercontinent Pangaea , with Eurasia to its east. One of
1140-490: Is designated as 'TTKSK' under the North American nomenclature system, was first detected in Uganda in 1998 and first characterised in 1999 (hence the name Ug99) and has since been detected in Kenya , Ethiopia , Eritrea , Sudan , Yemen , Iran , Tanzania , Mozambique , Zimbabwe , South Africa , and Egypt . There are now 15 known races of Ug99. They are all closely related and are believed to have evolved from
1216-535: Is in present-day Panama at the Darien Gap on the Colombia -Panama border, placing almost all of Panama within North America. Alternatively, some geologists physiographically locate its southern limit at the Isthmus of Tehuantepec , Mexico, with Central America extending southeastward to South America from this point. The Caribbean islands, or West Indies, are considered part of North America. The continental coastline
1292-630: Is long and irregular. The Gulf of Mexico is the largest body of water indenting the continent, followed by Hudson Bay . Others include the Gulf of Saint Lawrence and the Gulf of California . Before the Central American isthmus formed, the region had been underwater. The islands of the West Indies delineate a submerged former land bridge , which had connected North and South America via what are now Florida and Venezuela . There are several islands off
1368-548: Is part of North America geographically. In a geologic sense, Bermuda is not part of the Americas, but an oceanic island that was formed on the fissure of the Mid-Atlantic Ridge over 100 million years ago (mya). The nearest landmass to it is Cape Hatteras , North Carolina . However, Bermuda is often thought of as part of North America, especially given its historical, political and cultural ties to Virginia and other parts of
1444-686: Is the Morrison Formation of the western U.S. Canada is geologically one of the oldest regions in the world, with more than half of the region consisting of Precambrian rocks that have been above sea level since the beginning of the Palaeozoic era. Canada's mineral resources are diverse and extensive. Across the Canadian Shield and in the north there are large iron, nickel, zinc , copper, gold, lead, molybdenum , and uranium reserves. Large diamond concentrations have been recently developed in
1520-516: Is the humid subtropical climate . This area has the wettest cities in the contiguous U.S. , with annual precipitation reaching 67 in (1,700 mm) in Mobile, Alabama . Stretching from the borders of the humid continental and subtropical climates, and going west to the Sierra Nevada , south to the southern tip of Durango , north to the border with tundra climate, the steppe / desert climates are
1596-689: Is under way to marry resistance against present races with future needs for resistance against Ug99 whenever it arrives. Although Sr5 , Sr21 , Sr9e , Sr7b , Sr11 , Sr6 , Sr8a , Sr9g , Sr9b , Sr30 , Sr17 , Sr9a , Sr9d , Sr10 , SrTmp , Sr38 , and SrMcN are no longer effective in Lebanon , Sr11 , Sr24 , and Sr31 still are which is diagnostic for the absence of Ug99 from Lebanon. Detected in Iraq in 2019. Low-levels of TTKTT were detected in Nepal in 2023, but surveillance has not revealed any propagation in
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#17331154190331672-451: The Age of Discovery and the early modern period . Present-day cultural and ethnic patterns reflect interactions between European colonists, indigenous peoples , enslaved Africans , immigrants from Europe, Asia, and descendants of these respective groups. Europe's colonization in North America led to most North Americans speaking European languages, such as English , Spanish , and French , and
1748-509: The Archaic period began. The classic stage followed the Archaic period, and lasted from approximately the 6th to 13th centuries. Beginning in 1000 AD, the Norse were the first Europeans to begin exploring and ultimately colonizing areas of North America. In 1492, the exploratory voyages of Christopher Columbus led to a transatlantic exchange , including migrations of European settlers during
1824-551: The Bering Strait during the Early-Middle Holocene . Prior to the arrival of European explorers and colonists in North America, the natives of North America were divided into many different polities, ranging from small bands of a few families to large empires. They lived in several culture areas , which roughly correspond to geographic and biological zones that defined the representative cultures and lifestyles of
1900-576: The British Columbia Coast , Western Canada , and Northern Canada . In the U.S., they include New England , the Mid-Atlantic , South Atlantic states , East North Central states , West North Central states , East South Central states , West South Central states , Mountain states , and Pacific states . The Great Lakes region and the Pacific Northwest include areas in both Canada and
1976-863: The Caribbean Plate , whereas the Juan de Fuca Plate and Cocos Plate border the North American Plate on its western frontier. The continent can be divided into four great regions (each of which contains many subregions): the Great Plains stretching from the Gulf of Mexico to the Canadian Arctic ; the geologically young, mountainous west, including the Rocky Mountains , the Great Basin , California , and Alaska ;
2052-553: The Cordillera Isabelia , and the Cordillera de Talamanca . Between the mountain ranges lie fertile valleys that are suitable for the people; in fact, most of the population of Honduras, Costa Rica, and Guatemala live in valleys. Valleys are also suitable for the production of coffee, beans, and other crops. The indigenous peoples of the Americas have many creation myths , based on which they assert that they have been present on
2128-459: The East Coast to eastern North Dakota , and stretching down to Kansas , is the humid continental climate featuring intense seasons, with a large amount of annual precipitation, with places like New York City averaging 50 in (1,300 mm). Starting at the southern border of the humid continental climate and stretching to the Gulf of Mexico (whilst encompassing the eastern half of Texas)
2204-608: The Inuit of the high Arctic arrived in North America much later than other native groups, evidenced by the disappearance of Dorset culture artifacts from the archaeological record and their replacement by the Thule people . During the thousands of years of native habitation on the continent, cultures changed and shifted. One of the oldest yet discovered is the Clovis culture (c. 9550–9050 BCE) in modern New Mexico . Later groups include
2280-694: The Mississippian culture and related Mound building cultures, found in the Mississippi River valley and the Pueblo culture of what is now the Four Corners . The more southern cultural groups of North America were responsible for the domestication of many common crops now used around the world, such as tomatoes, squash , and maize . As a result of the development of agriculture in the south, many other cultural advances were made there. The Mayans developed
2356-505: The United States . North America covers an area of about 24,709,000 square kilometers (9,540,000 square miles), representing approximately 16.5% of the Earth 's land area and 4.8% of its total surface area. It is the third-largest continent by size after Asia and Africa , and the fourth-largest continent by population after Asia, Africa, and Europe . As of 2021 , North America's population
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2432-480: The first official name given to Mexico. North America includes several regions and subregions, each of which have their own respective cultural, economic, and geographic regions. Economic regions include several regions formalized in 20th- and 21st-century trade agreements, including NAFTA between Canada , Mexico , and the United States , and CAFTA between Central America , the Dominican Republic , and
2508-453: The 1490s, building cities, putting the resident indigenous populations to work, raising crops for Spanish settlers and panning gold to enrich the Spaniards. Much of the indigenous population died due to disease and overwork, spurring the Spaniards on to claim new lands and peoples. An expedition under the command of Spanish settler, Hernán Cortés , sailed westward in 1519 to what turned out to be
2584-615: The Arctic, making Canada one of the world's largest producers. Throughout the Shield, there are many mining towns extracting these minerals. The largest, and best known, is Sudbury , Ontario. Sudbury is an exception to the normal process of forming minerals in the Shield since there is significant evidence that the Sudbury Basin is an ancient meteorite impact crater . The nearby, but less-known Temagami Magnetic Anomaly has striking similarities to
2660-511: The BSR pathogen for decades. These resistant Sr genes, of which 50 are known, give wheat different resistances to stem rust. The virulence in Uganda was virulent against Sr31 and is specific to Ug99. The massive losses of wheat that have occurred have been devastating, but in recent years the wheat rust epidemic has been effectively controlled through selection and breeding for additional Sr genes. (In
2736-578: The Caribbean islands. France took the western half of Hispaniola and developed Saint-Domingue as a cane sugar producing colony worked by black slave labor. Britain took Barbados and Jamaica , and the Dutch and Danes took islands previously claimed by Spain. Britain did not begin settling on the North American mainland until a hundred years after the first Spanish settlements, since it sought first to control nearby Ireland . The first permanent English settlement
2812-616: The Cod fish", in reference to the abundance of cod fish on the East Coast . Waldseemüller used the Latin version of Vespucci's name, Americus Vespucius, in its feminine form of "America", following the examples of "Europa", "Asia", and "Africa". Americus originated from Medieval Latin Emericus (see Saint Emeric of Hungary ), coming from the Old High German name Emmerich . Map makers later extended
2888-487: The Global Rust Initiative. The BGRI has the overarching objective of systematically reducing the world’s vulnerability to stem , yellow , and leaf rusts of wheat and advocating/facilitating the evolution of a sustainable international system to contain the threat of wheat rusts and continue the enhancements in productivity required to withstand future global threats to wheat. Ug99 see text Ug99
2964-419: The North America's southeastern coast, Spanish explorer Juan Ponce de León , who had accompanied Columbus's second voyage, visited and named in 1513 La Florida . As the colonial period unfolded, Spain, England, and France appropriated and claimed extensive territories in North America eastern and southern coastlines. Spain established permanent settlements on the Caribbean islands of Hispaniola and Cuba in
3040-472: The Sudbury Basin. Its magnetic anomalies are very similar to the Sudbury Basin, and so it could be a second metal-rich impact crater. The Shield is also covered by vast boreal forests that support an important logging industry. The United States can be divided into twelve main geological provinces: Each province has its own geologic history and unique features. The geology of Alaska is typical of that of
3116-522: The U.S. North America occupies the northern portion of the landmass generally referred to as the New World, the Western Hemisphere , the Americas, or simply America, which, in many countries, is considered a single continent with North America a subcontinent . North America is the third-largest continent by area after Asia and Africa . North America's only land connection to South America
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3192-540: The United States has been the source of more varieties of dinosaurs than any other modern country. According to paleontologist Peter Dodson, this is primarily due to stratigraphy, climate and geography, human resources, and history. Much of the Mesozoic Era is represented by exposed outcrops in the many arid regions of the continent. The most significant Late Jurassic dinosaur-bearing fossil deposit in North America
3268-600: The United States, and Mexico. France , Italy , Portugal , Spain , Romania , Greece , and the countries of Latin America use a six-continent model , with the Americas viewed as a single continent and North America designating a subcontinent comprising Canada , the United States , Mexico, and Saint Pierre and Miquelon (politically part of France), and often including Greenland and Bermuda . North America has historically been known by other names, including Spanish North America, New Spain , and América Septentrional,
3344-527: The United States. North America is divided linguistically and culturally into two primary regions, Anglo-America and Latin America . Anglo-America includes most of North America, Belize , and Caribbean islands with English -speaking populations. There are also regions, including Louisiana and Quebec , with large Francophone populations; in Quebec , French is the official language. . The southern portion of North America includes Central America and non-English speaking Caribbean nations. The north of
3420-435: The area had shifted to the Aztec Empire , whose capital city Tenochtitlan was located further north in the Valley of Mexico . The Aztecs were conquered in 1521 by Hernán Cortés . During the so-called Age of Discovery , Europeans explored overseas and staked claims to various parts of North America, much of which was already settled by indigenous peoples. Upon Europeans' arrival in the " New World ", indigenous peoples had
3496-432: The continent maintains recognized regions as well. In contrast to the common definition of North America, which encompasses the whole North American continent, the term "North America" is sometimes used more narrowly to refer only to four nations, Canada, Greenland, Mexico, and the U.S. The U.S. Census Bureau includes Saint Pierre and Miquelon, but excludes Mexico from its definition. The term Northern America refers to
3572-452: The continent's coasts; principally, the Arctic Archipelago, the Bahamas , Turks and Caicos , the Greater and Lesser Antilles , the Aleutian Islands (some of which are in the Eastern Hemisphere proper), the Alexander Archipelago , the many thousand islands of the British Columbia Coast, and Newfoundland. Greenland , a self-governing Danish island, and the world's largest , is on the same tectonic plate (the North American Plate ) and
3648-410: The continent. The vast majority of North America is on the North American Plate. Parts of western Mexico, including Baja California, and of California , including the cities of San Diego , Los Angeles , and Santa Cruz , lie on the eastern edge of the Pacific Plate , with the two plates meeting along the San Andreas Fault . The southernmost portion of the continent and much of the West Indies lie on
3724-604: The cordillera, while the major islands of Hawaii consist of Neogene volcanics erupted over a hot spot . Central America is geologically active with volcanic eruptions and earthquakes occurring from time to time. In 1976 Guatemala was hit by a major earthquake , killing 23,000 people; Managua, the capital of Nicaragua, was devastated by earthquakes in 1931 and 1972, the last one killing about 5,000 people; three earthquakes devastated El Salvador, one in 1986 and two in 2001; one earthquake devastated northern and central Costa Rica in 2009, killing at least 34 people; in Honduras
3800-514: The cultures of the region commonly reflect Western traditions . However, relatively small parts of North America in Canada, the United States, Mexico, and Central America have indigenous populations that continue adhering to their respective pre-European colonial cultural and linguistic traditions. The Americas were named after the Italian explorer Amerigo Vespucci by German cartographers Martin Waldseemüller and Matthias Ringmann . Vespucci explored South America between 1497 and 1502, and
3876-410: The decades since, however, Sr31 -virulence has evolved in other strains in other locations. Patpour et al. , 2022 finds it in Spain and Siberia .) United States Department of Agriculture ( USDA ) researchers are testing genes to determine their Ug99 resistance, which will ultimately aid in the development of wheat varieties that will be able to fight off the rust. Resistance has been identified in
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#17331154190333952-447: The driest in the U.S. Highland climates cut from north to south of the continent, where subtropical or temperate climates occur just below the tropics, as in central Mexico and Guatemala . Tropical climates appear in the island regions and in the subcontinent's bottleneck, found in countries and states bathed by the Caribbean Sea or to the south of the Gulf of Mexico and the Pacific Ocean . Precipitation patterns vary across
4028-408: The end of the Canadian Shield, near the Great Lakes . Climate west of the Cascade Range is described as being temperate weather with average precipitation 20 inches (510 millimeters). Climate in coastal California is described to be Mediterranean , with average temperatures in cities like San Francisco ranging from 57 to 70 °F (14 to 21 °C) over the course of the year. Stretching from
4104-421: The first American inhabitants sailed from Beringia some 13,000 years ago, with widespread habitation of the Americas during the end of the Last Glacial Period , in what is known as the Late Glacial Maximum , around 12,500 years ago. The oldest petroglyphs in North America date from 15,000 to 10,000 years before present. Genetic research and anthropology indicate additional waves of migration from Asia via
4180-1029: The first such detection in the country. Found in Nepal in 2023. Virulent on Sr31 , Sr24 , and SrTmp . First detected in Kenya, Rwanda, Uganda, Eritrea, and Egypt in 2014 . Virulent on Sr31 and SrTmp . First detected in Kenya in 2014 . Differs from the original ( TTKSK ) by avirulence against Sr30 . Similar to TTHST . Virulent on Sr31 but avirulent on Sr30 . First detected in Kenya in 2014 . Differs from PTKSK by virulence against SrTmp . Differs from TTKTK by avirulence against Sr21 . Virulent on Sr31 and Sr24 , but avirulent on Sr21 . First detected in Kenya in 2013 . Virulent on Sr31 and Sr24 , but avirulent on Sr30 . First detected in Kenya in 2019 . Virulent to Sr31 , Sr24 , SrTmp , and Sr8155B1 . First detected in Kenya in 2020 . Virulent to Sr31 , Sr24 , and SrTmp , avirulent to Sr30 . Because stem rust (as with many fungi) spreads its spores across long distances with
4256-795: The geographic center of either the 50 states, the conterminous United States, or the North American continent." Nonetheless, there is a 4.6-meter (15 ft) field stone obelisk in Rugby claiming to mark the center. The North American continental pole of inaccessibility is located 1,650 km (1,030 mi) from the nearest coastline, between Allen and Kyle, South Dakota at 43°22′N 101°58′W / 43.36°N 101.97°W / 43.36; -101.97 ( Pole of Inaccessibility North America ) . Canada can be divided into roughly seven physiographic divisions: The lower 48 U.S. states can be divided into roughly eight physiographic divisions: Mexico can be divided into roughly fifteen physiographic divisions: North America
4332-411: The help of natural air currents , containment is difficult. Advances in fluid mechanics which are commonly used for meteorology have also aided Ug99 dispersal prediction. This is especially important for inter-continental, intermittent spread, such as from Eastern South Africa to Western Australia . Although Ug99 has not yet reached China , other stem rust races already have, and an effort
4408-419: The indigenous people who lived there, including the bison hunters of the Great Plains and the farmers of Mesoamerica . Native groups also are classified by their language families , which included Athapascan and Uto-Aztecan languages. Indigenous peoples with similar languages did not always share the same material culture , however, and were not necessarily always allies. Anthropologists speculate that
4484-400: The land since its creation, but there is no evidence that humans evolved there. The specifics of the initial settlement of the Americas by ancient Asians are subject to ongoing research and discussion. The traditional theory has been that hunters entered the Bering Land Bridge between eastern Siberia and present-day Alaska from 27,000 to 14,000 years ago. A growing viewpoint is that
4560-444: The mainland in Mexico. With local indigenous allies, the Spanish conquered the Aztec empire in central Mexico in 1521. Spain then established permanent cities in Mexico, Central America, and Spanish South America in the sixteenth century. Once Spaniards conquered the high civilization of the Aztecs and Incas, the Caribbean was a backwater of the Spanish empire. Other European powers began to intrude on areas claimed by Spain, including
4636-705: The middle into the main range of the Rockies and the coast ranges in California , Oregon , Washington , and British Columbia , with the Great Basin—a lower area containing smaller ranges and low-lying deserts—in between. The highest peak is Denali in Alaska. The U.S. Geographical Survey (USGS) states that the geographic center of North America is "6 miles [10 km] west of Balta, Pierce County, North Dakota " at about 48°10′N 100°10′W / 48.167°N 100.167°W / 48.167; -100.167 , about 24 kilometers (15 mi) from Rugby, North Dakota . The USGS further states that "No marked or monumented point has been established by any government agency as
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#17331154190334712-402: The name America to North America. In 1538, Gerardus Mercator used the term America on his world map of the entire Western Hemisphere . On his subsequent 1569 map , Mercator called North America "America or New India" ( America sive India Nova ). The Spanish Empire called its territories in North and South America "Las Indias", and the name given to the state body that oversaw the region
4788-493: The northernmost countries and territories of North America: the U.S., Bermuda , Canada, Greenland, and St. Pierre and Miquelon. Although the term does not refer to a unified region, Middle America includes Mexico, Central America, and the Caribbean. North America's largest countries by land area are Canada and the U.S., both of which have well-defined and recognized subregions. In Canada, these include (from east to west) Atlantic Canada , Central Canada , Canadian Prairies ,
4864-440: The northernmost extent of the island named Newfoundland , has provided unmistakable evidence of Norse settlement. Norse explorer Leif Erikson (c. 970–1020 CE) is thought to have visited the area. Erikson was the first European to make landfall on the continent (excluding Greenland). The Mayan culture was still present in southern Mexico and Guatemala when the Spanish conquistadors arrived, but political dominance in
4940-485: The original Ug99. Salcedo et al. , 2017 finds its Avr target, AvrSr35 . Races virulent on Sr35 benefit from nonfunctionalization of AvrSr35 by insertion of a mobile element . There are 15 races of Ug99, which (under the North American nomenclature system) have the designations TTKSK, TTKSF, TTKST, TTTSK, TTKSP, PTKSK, PTKST, TTKSF+, TTKTT, TTKTK, TTHSK, PTKTK, TTHST, TTKTT+, and TTHTT. They are all closely related and are believed to have evolved from
5016-503: The problem, and most subsequent efforts can be traced to his advocacy. It can cause up to 100% crop losses and is virulent against many resistance genes which have previously protected wheat against stem rust. Although Ug99- resistant varieties of wheat do exist, a screen of 200,000 wheat varieties used in 22 African and Asian countries found that only 5–10% of the area of wheat grown in these countries consisted of varieties with adequate resistance. The original race of Ug99, which
5092-421: The raised but relatively flat plateau of the Canadian Shield in the northeast; and the varied eastern region, which includes the Appalachian Mountains, the coastal plain along the Atlantic seaboard, and the Florida peninsula. Mexico, with its long plateaus and cordilleras , falls largely in the western region, although the eastern coastal plain does extend south along the Gulf. The western mountains are split in
5168-500: The region, and as such rainforest , monsoon , and savanna types can be found, with rains and high temperatures throughout the year. Notable North American fauna include the bison , black bear , jaguar , cougar , prairie dog , turkey , pronghorn , raccoon , coyote , and monarch butterfly . Notable plants that were domesticated in North America include tobacco , maize , squash , tomato , sunflower , blueberry , avocado , cotton , chile pepper , and vanilla . Laurentia
5244-423: The region. As of 2013 it was the US Director of National Intelligence 's assessment that Ug99 would arrive in South Asia soon, in the following few years. This was expected to cause worldwide supply disruptions because, although productivity was growing in Eastern Europe and could theoretically fill that gap, governments worldwide had shown a readiness to forbid exports. North America North America
5320-535: The research being conducted by the USDA , The United Kingdom’s Department for International Development (DFID) along with Bill & Melinda Gates Foundation , announced in February 2011 that they will be granting $ 40 million to a global project led by Cornell University to combat virulent strains of Ug99. The five-year grant to the Durable Rust Resistance in Wheat (DRRW) project supported attempts to identify new resistance genes as well as reproduce and distribute rust resistant wheat seeds to farmers. There has been
5396-415: The results of the formation of Pangaea was the Appalachian Mountains , which formed some 480 mya, making it among the oldest mountain ranges in the world. When Pangaea began to rift around 200 mya, North America became part of Laurasia , before it separated from Eurasia as its own continent during the mid- Cretaceous period. The Rockies and other western mountain ranges began forming around this time from
5472-540: Was called the Council of the Indies . The United Nations and its statistics division recognize North America as including three regions: Northern America, Central America , and the Caribbean . "Northern America" is a distinct term from "North America", excluding Central America, which itself may or may not include Mexico . In the limited context of regional trade agreements, the term is used to reference three nations: Canada,
5548-503: Was estimated as over 592 million people in 23 independent states , or about 7.5% of the world's population. In human geography , the terms "North America" and "North American" can refer to Canada, the United States, Mexico, and Greenland or, alternatively, Canada, Greenland and the US (Mexico being classified as part of Latin America ) or simply Canada and the US (Greenland being classified as either Arctic or European (due to its political status as
5624-790: Was in Jamestown, Virginia in 1607, followed by additional colonial establishments on the east coast from present-day Georgia in the south to Massachusetts in the north, forming the Thirteen Colonies of British America. The English did not establish settlements north or east of the St. Lawrence Valley in present-day Canada until after the conclusion of the American Revolutionary War . Britain's early settlements in present-day Canada included St. John's, Newfoundland in 1630 and Halifax, Nova Scotia in 1749. The first permanent French settlement
5700-468: Was the first European to suggest that the Americas represented a landmass not then known to the Europeans. In 1507, Waldseemüller published a world map, and placed the word "America" on the continent of present-day South America. The continent north of present-day Mexico was then referred to as Parias. On a 1553 world map published by Petrus Apianus , North America was called "Baccalearum", meaning "realm of
5776-1139: Was the first Ug99 race found to be virulent against Sr gene Sr24 . TTKST is now the predominant stem rust race in Kenya. Virulent on Sr31 . First detected in Kenya in 2007 , Tanzania in 2009 , Ethiopia in 2010 , Uganda in 2012 , and Rwanda in 2014 . Virulent on Sr31 and Sr36 . First detected by Visser et al. , 2011 in South Africa in 2007 . Avirulent on Sr31 and virulent on Sr24 . First detected in Ethiopia in 2007 , Kenya in 2009 , Yemen in 2009 , and South Africa in 2017 . Virulent on Sr31 and avirulent on Sr21 . First detected in Ethiopia in 2007 , Kenya in 2008 , South Africa in 2009 by Visser et al. , 2011, Eritrea and Mozambique and Zimbabwe in 2010 . Virulent on Sr31 and Sr24 , but avirulent on Sr21 . First detected in both South Africa and Zimbabwe in 2010 . Virulent against Sr9h . Avirulent on Sr31 but virulent on Sr9h . First detected in Kenya in 2014 . Also detected in Iraq in 2019,
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