Plants are multicellular, predominantly photosynthetic eukaryotes of the kingdom Plantae. Plants were treated as one of two kingdoms including all living things that were not animals, all algae and fungi were treated as plants. However, all current definitions of Plantae exclude the fungi and some algae, as well as the prokaryotes. By one definition, plants form the clade Viridiplantae, a group that includes the flowering plants and other gymnosperms and their allies, liverworts and the green algae, but excludes the red and brown algae. Green plants obtain most of their energy from sunlight via photosynthesis by primary chloroplasts that are derived from endosymbiosis with cyanobacteria, their chloroplasts contain b, which gives them their green color. Some plants are parasitic or mycotrophic and have lost the ability to produce normal amounts of chlorophyll or to photosynthesize. Plants are characterized by sexual reproduction and alternation of generations, although asexual reproduction is common.
There are about 320 thousand species of plants, of which the great majority, some 260–290 thousand, are seed plants. Green plants provide a substantial proportion of the world's molecular oxygen and are the basis of most of Earth's ecosystems on land. Plants that produce grain and vegetables form humankind's basic foods, have been domesticated for millennia. Plants have many cultural and other uses, as ornaments, building materials, writing material and, in great variety, they have been the source of medicines and psychoactive drugs; the scientific study of plants is known as a branch of biology. All living things were traditionally placed into one of two groups and animals; this classification may date from Aristotle, who made the distincton between plants, which do not move, animals, which are mobile to catch their food. Much when Linnaeus created the basis of the modern system of scientific classification, these two groups became the kingdoms Vegetabilia and Animalia. Since it has become clear that the plant kingdom as defined included several unrelated groups, the fungi and several groups of algae were removed to new kingdoms.
However, these organisms are still considered plants in popular contexts. The term "plant" implies the possession of the following traits multicellularity, possession of cell walls containing cellulose and the ability to carry out photosynthesis with primary chloroplasts; when the name Plantae or plant is applied to a specific group of organisms or taxon, it refers to one of four concepts. From least to most inclusive, these four groupings are: Another way of looking at the relationships between the different groups that have been called "plants" is through a cladogram, which shows their evolutionary relationships; these are not yet settled, but one accepted relationship between the three groups described above is shown below. Those which have been called "plants" are in bold; the way in which the groups of green algae are combined and named varies between authors. Algae comprise several different groups of organisms which produce food by photosynthesis and thus have traditionally been included in the plant kingdom.
The seaweeds range from large multicellular algae to single-celled organisms and are classified into three groups, the green algae, red algae and brown algae. There is good evidence that the brown algae evolved independently from the others, from non-photosynthetic ancestors that formed endosymbiotic relationships with red algae rather than from cyanobacteria, they are no longer classified as plants as defined here; the Viridiplantae, the green plants – green algae and land plants – form a clade, a group consisting of all the descendants of a common ancestor. With a few exceptions, the green plants have the following features in common, they undergo closed mitosis without centrioles, have mitochondria with flat cristae. The chloroplasts of green plants are surrounded by two membranes, suggesting they originated directly from endosymbiotic cyanobacteria. Two additional groups, the Rhodophyta and Glaucophyta have primary chloroplasts that appear to be derived directly from endosymbiotic cyanobacteria, although they differ from Viridiplantae in the pigments which are used in photosynthesis and so are different in colour.
These groups differ from green plants in that the storage polysaccharide is floridean starch and is stored in the cytoplasm rather than in the plastids. They appear to have had a common origin with Viridiplantae and the three groups form the clade Archaeplastida, whose name implies that their chloroplasts were derived from a single ancient endosymbiotic event; this is the broadest modern definition of the term'plant'. In contrast, most other algae not only have different pigments but have chloroplasts with three or four surrounding membranes, they are not close relatives of the Archaeplastida having acquired chloroplasts separately from ingested or symbiotic green and red algae. They are thus not included in the broadest modern definition of the plant kingdom, although they were in the past; the green plants or Viridiplantae were traditionally divided into the green algae (including
The term cultivar most refers to an assemblage of plants selected for desirable characters that are maintained during propagation. More cultivar refers to the most basic classification category of cultivated plants in the International Code of Nomenclature for Cultivated Plants. Most cultivars arose in cultivation. Popular ornamental garden plants like roses, daffodils and azaleas are cultivars produced by careful breeding and selection for floral colour and form; the world's agricultural food crops are exclusively cultivars that have been selected for characters such as improved yield and resistance to disease, few wild plants are now used as food sources. Trees used in forestry are special selections grown for their enhanced quality and yield of timber. Cultivars form a major part of Liberty Hyde Bailey's broader group, the cultigen, defined as a plant whose origin or selection is due to intentional human activity. A cultivar is not the same as a botanical variety, a taxonomic rank below subspecies, there are differences in the rules for creating and using the names of botanical varieties and cultivars.
In recent times, the naming of cultivars has been complicated by the use of statutory patents for plants and recognition of plant breeders' rights. The International Union for the Protection of New Varieties of Plants offers legal protection of plant cultivars to persons or organisations that introduce new cultivars to commerce. UPOV requires that a cultivar be "distinct, uniform", "stable". To be "distinct", it must have characters that distinguish it from any other known cultivar. To be "uniform" and "stable", the cultivar must retain these characters in repeated propagation; the naming of cultivars is an important aspect of cultivated plant taxonomy, the correct naming of a cultivar is prescribed by the Rules and Recommendations of the International Code of Nomenclature for Cultivated Plants. A cultivar is given a cultivar name, which consists of the scientific Latin botanical name followed by a cultivar epithet; the cultivar epithet is in a vernacular language. For example, the full cultivar name of the King Edward potato is Solanum tuberosum'King Edward'.'King Edward' is the cultivar epithet, according to the Rules of the Cultivated Plant Code, is bounded by single quotation marks.
The word cultivar originated from the need to distinguish between wild plants and those with characteristics that arose in cultivation, presently denominated cultigens. This distinction dates to the Greek philosopher Theophrastus, the "Father of Botany", keenly aware of this difference. Botanical historian Alan Morton noted that Theophrastus in his Historia Plantarum "had an inkling of the limits of culturally induced changes and of the importance of genetic constitution"; the International Code of Nomenclature for algae and plants uses as its starting point for modern botanical nomenclature the Latin names in Linnaeus' Species Plantarum and Genera Plantarum. In Species Plantarum, Linnaeus enumerated all plants known to him, either directly or from his extensive reading, he recognised the rank of varietas and he indicated these varieties with letters of the Greek alphabet, such as α, β, λ, before the varietal name, rather than using the abbreviation "var." as is the present convention. Most of the varieties that Linnaeus enumerated were of "garden" origin rather than being wild plants.
In time the need to distinguish between wild plants and those with variations, cultivated increased. In the nineteenth century many "garden-derived" plants were given horticultural names, sometimes in Latin and sometimes in a vernacular language. From circa the 1900s, cultivated plants in Europe were recognised in the Scandinavian and Slavic literature as stamm or sorte, but these words could not be used internationally because, by international agreement, any new denominations had to be in Latin. In the twentieth century an improved international nomenclature was proposed for cultivated plants. Liberty Hyde Bailey of Cornell University in New York, United States created the word cultivar in 1923 when he wrote that: The cultigen is a species, or its equivalent, that has appeared under domestication – the plant is cultigenous. I now propose another name, for a botanical variety, or for a race subordinate to species, that has originated under cultivation, it is the equivalent of the botanical variety except in respect to its origin.
In that essay, Bailey used only the rank of species for the cultigen, but it was obvious to him that many domesticated plants were more like botanical varieties than species, that realization appears to have motivated the suggestion of the new category of cultivar. Bailey created the word cultivar, assumed to be a portmanteau of cultivated and variety. Bailey never explicitly stated the etymology of cultivar, it has been suggested that it is instead a contraction of cultigen and variety, which seems correct; the neologism cultivar was promoted as "euphonious" and "free from ambiguity". The first Cultivated Plant Code of 1953 subsequently commended its use, by 1960 it had achieved common international acceptance; the words cultigen and cultivar may be confused with
Lists of cultivars
The lists of cultivars in the table below are indexes of plant cultivars and strains. A cultivar is a plant, selected for desirable characteristics that can be maintained by propagation; the plants listed may be ornamental, and/or edible. Several of them bear edible fruit. Plants are selectively bred for other hereditary traits; when developing a new variety, a plant breeder might value such characteristics as appearance, disease resistance, hardiness. In the cultivation of edible fruit and vegetables, nutritional value, shelf life, crop yield are among the potential considerations; some of the lists use the word variety instead of cultivar. In most of these lists, variety refers to a cultivar, recognised by the International Union for the Protection of New Varieties of Plants. A cultivar must meet certain criteria. In a few lists, variety means something else: a taxonomic rank below that of species. If the species' binomial name is followed by the word var. and another name, a botanical variety, not a cultivar.
Cultivated plant taxonomy Genetic variation Horticulture Introduction to genetics Landrace Wehner, Todd C.. "Vegetable Cultivar Descriptions for North America". North Carolina State University. Retrieved 9 April 2012
Community Plant Variety Office
The Community Plant Variety Office is an agency of the European Union, located in Angers, France. It was established in 1994, its task is to administer a system of plant variety rights known as plant breeders' rights, a form of intellectual property right relating to plants. The CPVO manages the largest system of plant variety rights in the World. Since the creation of the CPVO in 1995 the office has received over 61,000, of which it granted over 47,000 applications, with over 25,000 titles in force. Plant variety rights allow plant breeders to protect new varieties; the CPVO was created to encourage the creation of new plant varieties in the European Union, through the provision of better intellectual property protection for plant breeders. The Community plant variety right, gives the holder of this right an exclusive right to market the protected variety within the territory of the European Union; the Community PVR is valid for a period of 25 to 30 years. The Breeders’ Exemption ensures that anyone is allowed to use protected varieties as a basis for the creation of new varieties.
The Breeders’ Exemption exists to ensure that PVR and the need to reward breeders for their work is balanced with the need for new & better varieties to reach & benefit the consumer as as possible. It ensures the continued production of new varieties as breeders need access to as much genetic resources as possible, including protected varieties, in order to create new varieties; the CPVO system of PVR protection means that only one application need be made in order to attain EU wide protection. Before its introduction, EU wide protection was only possible through obtaining national plant variety rights from the individual member states; that option still exists today. As part of the application procedure, each candidate variety is tested by an examination office; the examination offices are based in the member states. The examination offices determine whether the variety is distinct and stable – this is called a DUS test; the CPVO does not own any technical infrastructure. The results of the DUS tests are used by the CPVO when taking the decision to grant or refuse a PVR application.
Based in Angers, France the CPVO was created by the Council Regulation 2100/94 and has been operational since the 27 April 1995. The CPVO is self-financed, it neither contributes to the EU budget. The CPVO’s budget is principally derived from PVR application fees paid by breeders who wish to protect their creations; the President of the CPVO is appointed by the Council of the European Union. The President is responsible for the overall functioning of the CPVO – this includes the implementation of the CPVO’s legislative duties and all operational aspects of the CPVO; the current president of the CPVO is Martin Ekvad. Ekvad was appointed to this position in 2011. Prior to his appointment, Ekvad held the position of Head of the Legal Unit of the CPVO from 2003 to 2011; the CPVO is supervised by the Administrative Council of the CPVO. The AC is made up of representatives from across the 28 member states, representatives from the European Commission and observer organisations; the AC is the budgetary authority of the CPVO and adopts the responsibilities annual work programme.
Community Plant Variety Office
Horticulture has been defined as the culture of plants for food and beauty. A more precise definition can be given as "The cultivation and sale of fruits, vegetables, ornamental plants, flowers as well as many additional services", it includes plant conservation, landscape restoration, soil management and garden design and maintenance, arboriculture. In contrast to agriculture, horticulture does not include large-scale crop production or animal husbandry. Horticulturists apply their knowledge and technologies used to grow intensively produced plants for human food and non-food uses and for personal or social needs, their work involves plant propagation and cultivation with the aim of improving plant growth, quality, nutritional value, resistance to insects and environmental stresses. They work as gardeners, therapists and technical advisors in the food and non-food sectors of horticulture. Horticulture refers to the growing of plants in a field or garden; the word horticulture is modeled after agriculture, comes from the Latin hortus "garden" and cultūra "cultivation", from cultus, the perfect passive participle of the verb colō "I cultivate".
Hortus is cognate with the native English word yard and the borrowed word garden. The major areas of Horticulture include: Arboriculture is the study of, the selection, plant and removal of, individual trees, shrubs and other perennial woody plants. Turf management includes all aspects of the production and maintenance of turf grass for sports, leisure use or amenity use. Floriculture includes the marketing of floral crops. Study of flower cultivation. Landscape horticulture includes the production and maintenance of landscape plants. Olericulture includes the marketing of vegetables. Pomology includes the marketing of pome fruits. Viticulture includes the marketing of grapes. Oenology includes all aspects of winemaking. Postharvest physiology involves maintaining the quality of and preventing the spoilage of plants and animals. Horticulture has a long history; the study and science of horticulture dates all the way back to the times of Cyrus the Great of ancient Persia, has been going on since, with present-day horticulturists such as Freeman S. Howlett and Luther Burbank.
The practice of horticulture can be retraced for many thousands of years. The cultivation of taro and yam in Papua New Guinea dates back to at least 6950–6440 cal BP; the origins of horticulture lie in the transition of human communities from nomadic hunter-gatherers to sedentary or semi-sedentary horticultural communities, cultivating a variety of crops on a small scale around their dwellings or in specialized plots visited during migrations from one area to the next. In the Pre-Columbian Amazon Rainforest, natives are believed to have used biochar to enhance soil productivity by smoldering plant waste. European settlers called it Terra Preta de Indio. In forest areas such horticulture is carried out in swiddens. A characteristic of horticultural communities is that useful trees are to be found planted around communities or specially retained from the natural ecosystem. Horticulture differs from agriculture in two ways. First, it encompasses a smaller scale of cultivation, using small plots of mixed crops rather than large fields of single crops.
Secondly, horticultural cultivations include a wide variety of crops including fruit trees with ground crops. Agricultural cultivations however as a rule focus on one primary crop. In pre-contact North America the semi-sedentary horticultural communities of the Eastern Woodlands contrasted markedly with the mobile hunter-gatherer communities of the Plains people. In Central America, Maya horticulture involved augmentation of the forest with useful trees such as papaya, cacao and sapodilla. In the cornfields, multiple crops were grown such as beans, squash and chilli peppers, in some cultures tended or by women. Since 1804 The Royal Horticultural Society, a UK charity, leads on the encouragement and improvement of the science and practice of horticulture in all its branches and shares this knowledge through its community and learning programmes, world class gardens and shows; the oldest Horticultural society in the world, founded in 1768, is the Ancient Society of York Florists. They still have four shows a year in York, UK.
The professional body representing horticulturists in Great Britain and Ireland is the Institute of Horticulture. The IOH has an international branch for members outside of these islands; the International Society for Horticultural Science promotes and encourages research and education in all branches of horticultural science. The American Society of Horticultural Science promotes and encourages research and education in all branches of horticultural science in the Americas; the Australian Society of Horticultural Science was established in 1990 as a professional society for the promotion and enhancement of Australian horticultural science and industry. The National Junior Horticultural Association was established in 1934 and was the first organisation in the world dedicated to youth and horticulture. NJHA programs are designed to help young people obtain a basic understanding of, develop skills in, the ever-expanding art and science of horticulture; the New Zealand Horticulture Institute. The Global Horticulture Initiative (GlobalHo
Viticulture or winegrowing is the cultivation and harvesting of grapes. It is a branch of the science of horticulture. While the native territory of Vitis vinifera, the common grape vine, ranges from Western Europe to the Persian shores of the Caspian Sea, the vine has demonstrated high levels of adaptability to new environments. For this reason, viticulture can be found on every continent except Antarctica. Duties of the viticulturist include monitoring and controlling pests and diseases, irrigation, canopy management, monitoring fruit development and characteristics, deciding when to harvest, vine pruning during the winter months. Viticulturists are intimately involved with winemakers, because vineyard management and the resulting grape characteristics provide the basis from which winemaking can begin. A great number of varieties are now approved in the European Union as true grapes for winegrowing and viticulture; the earliest evidence of grape vine cultivation and winemaking dates back 7,000 years.
The history of viticulture is related to the history of wine, with evidence that humans cultivated wild grapes to make wine as far back as the Neolithic period. Evidence suggests that some of the earliest domestication of Vitis vinifera occurred in the area of the modern countries Georgia and Armenia; the oldest-known winery was discovered in the "Areni-1" cave in Armenia. Dated to c. 4100 BC, the site contained a wine press, fermentation vats and cups. Archaeologists found V. vinifera seeds and vines. Commenting on the importance of the find, McGovern said, "The fact that winemaking was so well developed in 4000 BC suggests that the technology goes back much earlier." There is evidence of grape domestication in the Near East in the early Bronze Age, around 3200 BC. Evidence of ancient viticulture is provided by cuneiform sources, plant remains, historical geography, archaeological excavations; the remnants of ancient wine jars have been used to determine the culture of wine consumption and cultivated grape species.
In addition to winemaking, grapes have been grown for the production of raisins. The earliest act of cultivation appears to have been the favoring of hermaphroditic members of the Vitis vinifera species over the barren male vines and the female vines, which were dependent on a nearby male for pollination. With the ability to pollinate itself, over time the hermaphroditic vines were able to sire offspring that were hermaphroditic. At the end of the 5th century BC, the Greek historian Thucydides wrote: The period that Thucydides was most referencing was the time between 3000 BC and 2000 BC, when viticulture emerged in force in Asia Minor and the Cyclades Islands of the Aegean Sea. During this period, grape cultivation developed from an aspect of local consumption to an important component of international economies and trade. From 1200 BC to 900 BC, the Phoenicians developed viticulture practices that were used in Carthage. Around 500 BC, the Carthaginian writer Mago recorded such practices in a two-volume work, one of the few artifacts to survive the Roman destruction of Carthage during the Third Punic War.
The Roman statesman Cato the Elder was influenced by these texts, around 160 BC he wrote De Agricultura, which expounded on Roman viticulture and agriculture. Around 65 AD, the Roman writer Columella produced the most detailed work on Roman viticulture in his twelve-volume text De Re Rustica. Columella's work is one of the earliest to detail trellis systems for raising vines off the ground. Columella advocated the use of stakes versus the accepted practice of training vines to grow up along tree trunks; the benefits of using stakes over trees was to minimize the dangers associated with climbing trees, necessary to prune the dense foliage in order to give the vines sunlight, to harvest them. Roman expansion across Western Europe brought Roman viticulture to the areas that would become some of the world's best-known winegrowing regions: the Spanish Rioja, the German Mosel, the French Bordeaux, Burgundy and Rhône. Roman viticulturists were among the first to identify steep hillsides as one of the better locations to plant vines, because cool air runs downhill and gathers at the bottom of valleys.
While some cool air is beneficial, too much can rob the vine of the heat it needs for photosynthesis, in winter it increases the risk of frost. In the Middle Ages, Catholic monks were the most prominent viticulturists of the time period. Around this time, an early system of Metayage emerged in France with laborers working the vineyards under contractual agreements with the landowners. In most cases, the prendeurs were given flexibility in selecting their crop and developing their own vineyard practice. In northern Europe, the weather and climate posed difficulties for grape cultivation, so certain species were selected that better suited the environment. Most vineyards grew white varieties of grape, which are more resistant to the damp and cold climates. A few species of red grape, such as the Pinot Noir, were introduced. Les Très Riches Heures du duc de Berry dates back to 1416 and depicts horticulture and viticulture in France; the images illustrate peasants bending down to prune grapes from vines behind castle walls.
Additional illustrations depict grape vines being harvested, with each vine being cut to three spurs around knee height. Many of the viticultural practices developed in this time period would become staples of European viticulture until the 18th century. Varietals were studied more intently to see which vines were the most suitable for a particular area. Around this
Law is a system of rules that are created and enforced through social or governmental institutions to regulate behavior. It has been defined both as "the Science of Justice" and "the Art of Justice". Law is a system that regulates and ensures that individuals or a community adhere to the will of the state. State-enforced laws can be made by a collective legislature or by a single legislator, resulting in statutes, by the executive through decrees and regulations, or established by judges through precedent in common law jurisdictions. Private individuals can create binding contracts, including arbitration agreements that may elect to accept alternative arbitration to the normal court process; the formation of laws themselves may be influenced by a constitution, written or tacit, the rights encoded therein. The law shapes politics, economics and society in various ways and serves as a mediator of relations between people. A general distinction can be made between civil law jurisdictions, in which a legislature or other central body codifies and consolidates their laws, common law systems, where judge-made precedent is accepted as binding law.
Religious laws played a significant role in settling of secular matters, is still used in some religious communities. Islamic Sharia law is the world's most used religious law, is used as the primary legal system in some countries, such as Iran and Saudi Arabia; the adjudication of the law is divided into two main areas. Criminal law deals with conduct, considered harmful to social order and in which the guilty party may be imprisoned or fined. Civil law deals with the resolution of lawsuits between individuals and/or organizations. Law provides a source of scholarly inquiry into legal history, economic analysis and sociology. Law raises important and complex issues concerning equality and justice. Numerous definitions of law have been put forward over the centuries; the Third New International Dictionary from Merriam-Webster defines law as: "Law is a binding custom or practice of a community. The Dictionary of the History of Ideas published by Scribner's in 1973 defined the concept of law accordingly as: "A legal system is the most explicit, institutionalized, complex mode of regulating human conduct.
At the same time, it plays only one part in the congeries of rules which influence behavior, for social and moral rules of a less institutionalized kind are of great importance." There have been several attempts to produce "a universally acceptable definition of law". In 1972, one source indicated. McCoubrey and White said that the question "what is law?" has no simple answer. Glanville Williams said that the meaning of the word "law" depends on the context in which that word is used, he said that, for example, "early customary law" and "municipal law" were contexts where the word "law" had two different and irreconcilable meanings. Thurman Arnold said that it is obvious that it is impossible to define the word "law" and that it is equally obvious that the struggle to define that word should not be abandoned, it is possible to take the view that there is no need to define the word "law". The history of law links to the development of civilization. Ancient Egyptian law, dating as far back as 3000 BC, contained a civil code, broken into twelve books.
It was based on the concept of Ma'at, characterised by tradition, rhetorical speech, social equality and impartiality. By the 22nd century BC, the ancient Sumerian ruler Ur-Nammu had formulated the first law code, which consisted of casuistic statements. Around 1760 BC, King Hammurabi further developed Babylonian law, by codifying and inscribing it in stone. Hammurabi placed several copies of his law code throughout the kingdom of Babylon as stelae, for the entire public to see; the most intact copy of these stelae was discovered in the 19th century by British Assyriologists, has since been transliterated and translated into various languages, including English, Italian and French. The Old Testament dates back to 1280 BC and takes the form of moral imperatives as recommendations for a good society; the small Greek city-state, ancient Athens, from about the 8th century BC was the first society to be based on broad inclusion of its citizenry, excluding women and the slave class. However, Athens had no legal science or single word for "law", relying instead on the three-way distinction between divine law, human decree and custom.
Yet Ancient Greek law contained major constitutional innovations in the development of democracy. Roman law was influenced by Greek philosophy, but its detailed rules were developed by professional jurists and were sophisticated. Over the centuries between the rise and decline of the Roman Empire, law was adapted to cope with the changing social situations and underwent major codification under Theodosius II and Justinian I. Although codes were replaced by custom and case law during the Dark Ages, Roman law was rediscovered around the 11th century when medieval legal scholars began to research Roman codes and adapt their concepts. Latin legal maxims were compiled for guidance. In medieval England, royal