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Seed Orchard
A seed orchard is an intensively-managed plantation of specifically arranged trees for the mass production of genetically improved seeds to create plants, or seeds for the establishment of new forests. General Seed orchards are a common method of mass-multiplication for transferring genetically improved material from breeding populations to production populations (forests) and in this sense are often referred to as "multiplication" populations. A seed orchard is often composed of grafts (vegetative copies) of selected genotypes, but seedling seed orchards also occur mainly to combine orchard with progeny testing. Seed orchards are the strong link between breeding programs and plantation establishment. They are designed and managed to produce seeds of superior genetic quality compared to those obtained from seed production areas, seed stands, or unimproved stands. Material and connection with breeding population In first generation seed orchards, the parents usually are phenotypical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Verger Mimizan
A verger (or virger, so called after the staff of the office, or wandsman (British)) is a person, usually a layperson, who assists in the ordering of religious services, particularly in Anglican churches. Etymology The title of ''verger'' arises from the ceremonial rod they traditionally carried known as a virge (from the Latin , "branch, staff, rod"; see virgule). The Maces of State used in the House of Lords and the House of Commons of the British Parliament are examples of another modern use of the medieval virge. In former times, a verger might have needed to use his virge to keep back animals or an overenthusiastic crowd from the personage he was escorting or even to discipline unruly choristers. History The office of verger has its roots in the early days of the Church of England's history. The Order shares certain similarities with the former Minor Orders of Porter and Acolyte. Historically, vergers were responsible for the order and upkeep of a house of worship, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plantation
A plantation is an agricultural estate, generally centered on a plantation house, meant for farming that specializes in cash crops, usually mainly planted with a single crop, with perhaps ancillary areas for vegetables for eating and so on. The crops that are grown include cotton, coffee, tea, cocoa, sugar cane, opium, sisal, oil seeds, oil palms, fruits, rubber trees and forest trees. Protectionist policies and natural comparative advantage have sometimes contributed to determining where plantations are located. In modern use the term is usually taken to refer only to large-scale estates, but in earlier periods, before about 1800, it was the usual term for a farm of any size in the southern parts of British North America, with, as Noah Webster noted, "farm" becoming the usual term from about Maryland northwards. It was used in most British colonies, but very rarely in the United Kingdom itself in this sense. There, as also in America, it was used mainly for tree plantations, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genotype
The genotype of an organism is its complete set of genetic material. Genotype can also be used to refer to the alleles or variants an individual carries in a particular gene or genetic location. The number of alleles an individual can have in a specific gene depends on the number of copies of each chromosome found in that species, also referred to as ploidy. In diploid species like humans, two full sets of chromosomes are present, meaning each individual has two alleles for any given gene. If both alleles are the same, the genotype is referred to as homozygous. If the alleles are different, the genotype is referred to as heterozygous. Genotype contributes to phenotype, the observable traits and characteristics in an individual or organism. The degree to which genotype affects phenotype depends on the trait. For example, the petal color in a pea plant is exclusively determined by genotype. The petals can be purple or white depending on the alleles present in the pea plant. Howev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tree Breeding
Tree breeding is the application of genetic, reproductive biology and economics principles to the genetic improvement and management of forest trees. In contrast to the selective breeding of livestock, arable crops, and horticultural flowers over the last few centuries, the breeding of trees, with the exception of fruit trees, is a relatively recent occurrence. A typical forest tree breeding program starts with selection of superior phenotypes (plus trees) in a natural or planted forest, often based on growth rate, tree form and site adaptation traits. This application of mass selection improves the mean performance of the forest. Offspring is obtained from selected trees and grown in test plantations that act as genetic trials. Based on such tests the best genotypes among the parents can be selected. Selected trees are typically multiplied by either seeds or grafting and seed orchards are established when the preferred output is improved seed. Alternatively, the best genotypes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seed Production And Gene Diversity
Genetic diversity is often a major consideration in e g forest crops. Group coancestry of a population Consider the gene pool of a seed orchard crop or other source of seeds with parents. The gene pool is large as there are many seeds in a seed crop, so there is no genetic drift. The probability that the first gene originates from genotype i in the seed orchard is pi, and the probability that the second originates from genotype j is pj. The probability that these two genes originate from the orchard genotypes i and j are identical by descent (IBD) is θij. This is the Malecot's method of coancestry Malecot's coancestry coefficient, f, refers to an indirect measure of genetic similarity of two individuals which was initially devised by the French mathematician Gustave Malécot. f is defined as the probability that any two alleles, sampled ... (or "coefficient of kinship"; "coefficient of relationship" is a similar measure which can be computed) between genotype i and j. The p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anemophily
Anemophily or wind pollination is a form of pollination whereby pollen is distributed by wind. Almost all gymnosperms are anemophilous, as are many plants in the order Poales, including grasses, sedges, and rushes. Other common anemophilous plants are oaks, pecans, pistachios, sweet chestnuts, alders and members of the family Juglandaceae (hickory or walnut family). Approximately 12% of plants across the globe are pollinated by anemophily, including cereal crops like rice and corn and other prominent crop plants like wheat, rye, barley, and oats. In addition, many pines, spruces, and firs are wind-pollinated, and. Syndrome Features of the wind-pollination syndrome include a lack of scent production, a lack of showy floral parts (resulting in small, inconspicuous flowers), reduced production of nectar, and the production of enormous numbers of pollen grains. This distinguishes them from entomophilous and zoophilous species (whose pollen is spread by insects and vertebrates re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Diversity
Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species, it ranges widely from the number of species to differences within species and can be attributed to the span of survival for a species. It is distinguished from ''genetic variability'', which describes the tendency of genetic characteristics to vary. Genetic diversity serves as a way for populations to adapt to changing environments. With more variation, it is more likely that some individuals in a population will possess variations of alleles that are suited for the environment. Those individuals are more likely to survive to produce offspring bearing that allele. The population will continue for more generations because of the success of these individuals. The academic field of population genetics includes several hypotheses and theories regarding genetic diversity. The neutral theory of evolution proposes that diversity is the result of the accumulation of neutral substitutions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southern Yellow Pine
In ecology and forestry, yellow pine refers to a number of conifer species that tend to grow in similar plant communities and yield similar strong wood. In the Western United States, yellow pine refers to Jeffrey pine or ponderosa pine. In the Southeastern United States, yellow pine refers to longleaf pine, shortleaf pine, slash pine, or loblolly pine. In the United Kingdom, yellow pine refers to eastern white pine or Scots pine. In New Zealand, it refers to '' Halocarpus biformis''. Western United States The Jeffrey pine and the ponderosa pine are common in drier montane areas of the Sierra Nevada. They are often confused by casual observers. Across the remainder of the American West, Jeffrey pine is absent, with ponderosa pine being the sole yellow pine. Jeffrey pine is more stress tolerant than ponderosa pine in the Sierra Nevada. At higher elevations, on poorer soils, in colder climates, and in drier climates, Jeffrey pine replaces ponderosa as the dominant tree (Jeffrey pi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ramet
A clonal colony or genet is a group of genetically identical individuals, such as plants, fungi, or bacteria, that have grown in a given location, all originating vegetatively, not sexually, from a single ancestor. In plants, an individual in such a population is referred to as a ramet. In fungi, "individuals" typically refers to the visible fruiting bodies or mushrooms that develop from a common mycelium which, although spread over a large area, is otherwise hidden in the soil. Clonal colonies are common in many plant species. Although many plants reproduce sexually through the production of seed, reproduction occurs by underground stolons or rhizomes in some plants. Above ground, these plants most often appear to be distinct individuals, but underground they remain interconnected and are all clones of the same plant. However, it is not always easy to recognize a clonal colony especially if it spreads underground and is also sexually reproducing. Methods of establishment With m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Self-pollination
Self-pollination is a form of pollination in which pollen from the same plant arrives at the Stigma (botany), stigma of a flower (in flowering plants) or at the ovule (in gymnosperms). There are two types of self-pollination: in autogamy, pollen is transferred to the Stigma (botany), stigma of the same flower; in geitonogamy, pollen is transferred from the anther of one flower to the stigma of another flower on the same flowering plant, or from Microsporangia, microsporangium to ovule within a single (Monoecy, monoecious) gymnosperm. Some plants have mechanisms that ensure autogamy, such as flowers that do not open (cleistogamy), or stamens that move to come into contact with the stigma. The term selfing that is often used as a synonym, is not limited to self-pollination, but also applies to other types of self-fertilization. Occurrence Few plants self-pollinate without the aid of pollen vectors (such as wind or insects). The mechanism is seen most often in some legumes such as p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scots Pine
''Pinus sylvestris'', the Scots pine (UK), Scotch pine (US) or Baltic pine, is a species of tree in the pine family Pinaceae that is native to Eurasia. It can readily be identified by its combination of fairly short, blue-green leaves and orange-red bark. Description ''Pinus sylvestris'' is an evergreen coniferous tree growing up to in height and in trunk diameter when mature, exceptionally over tall and in trunk diameter on very productive sites. The tallest on record is a tree over 210 years old tree growing in Estonia which stands at . The lifespan is normally 150–300 years, with the oldest recorded specimens in Lapland, Northern Finland over 760 years. The bark is thick, flaky and orange-red when young to scaly and gray-brown in maturity, sometimes retaining the former on the upper portion.Trees for LifeSpecies profile: Scots pine/ref> The habit of the mature tree is distinctive due to its long, bare and straight trunk topped by a rounded or flat-topped mass of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Double-pair Mating
Double-pair mating (DPM) is a mating (crossing) design used in plant breeding. Each individual is mated with two others. Principles In Fig. 1 a connected variant of DPM is shown. DPM is an efficient mating design in balanced breeding programmes, where equal contribution from each breeding population member is desired. With DPM the number of new families created is equal to the number of individuals mated. DPM allows to efficiently utilise positive assortative mating for more efficient use of the breeding population members for deployment to seed orchards.Ruotsalainen, S. 2002. Managing breeding stock in the initiation of a long-term tree breeding program. PhD-thesis. Finnish Forest Research Institute, Research Papers 875., 95 + 61 /ref> In comparison with single pair mating, DPM has the advantages that the genes from the individual are transmitted to next generation even if one of the crosses fails; that safer estimates of breeding values of the parents get possible (useful for s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
