The biologist and evolution theorist showed in the late 1800s that cross-fertilization of plants - in which sex cells are fused between crop varieties of the same species - creates a more vigorous breed than those that are self-fertilized.
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Throats are slightly hairy. Stamens produce large amounts of pollen. The germination rates of self-fertilized seeds is about 80%.
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Thus self- fertilization is avoided, and cross-fertilization is favored. Although avoided, self-fertilization is still possible in B. schlosseri. Self- fertilized eggs develop with a substantially higher frequency of anomalies during cleavage than cross-fertilized eggs (23% vs. 1.6%). Also a significantly lower percentage of larvae derived from self-fertilized eggs metamorphose, and the growth of the colonies derived from their metamorphosis is significantly lower.
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Thus self- fertilization is avoided, and cross-fertilization is favored. Although avoided, self-fertilization is still possible in B. schlosseri. Self- fertilized eggs develop with a substantially higher frequency of anomalies during cleavage than cross-fertilized eggs (23% vs. 1.6%). Also a significantly lower percentage of larvae derived from self-fertilized eggs metamorphose, and the growth of the colonies derived from their metamorphosis is significantly lower.
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Self-fertilized eggs develop with a substantially higher frequency of anomalies during cleavage than cross-fertilized eggs (23.1% vs. 1.6%). Also a significantly lower percentage of larvae derived from self-fertilized eggs metamorphose (51.5% vs 87.2%), and the growth of the colonies derived from their metamorphosis is significantly slower. These observations suggest that self-fertilization leads to inbreeding depression associated with developmental deficits likely arising from expression of deleterious recessive mutations.
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The flowering period extends from July through October. The hermaphroditic flowers are either self-fertilized (autogamy) or pollinated by insects (entomogamy). The seeds are an achene that ripens in October.
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Some nematodes, such as Heterorhabditis spp., undergo a process called endotokia matricida: intrauterine birth causing maternal death. Some nematodes are hermaphroditic, and keep their self- fertilized eggs inside the uterus until they hatch. The juvenile nematodes then ingest the parent nematode.
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The flowering period extends from May to July in the Northern Hemisphere. The flowers are either self- fertilized (autogamy) or pollinated by insects such as bees and butterflies (entomogamy). The seeds ripen from August to September and are dispersed by gravity alone (barochory).
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As an annual, self-fertilized grass that is cultivated for its grains, Khorasan wheat looks very similar to common wheat. However, its grains are twice the size of modern wheat kernel, with a Thousand-kernel Weight up to 60g. They contain more proteins, lipids, amino acids, vitamins and minerals than modern wheat. The grain has an amber colour and a high vitreousness.
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E. virginiana relies upon ant pollination to produce cross pollinated seeds along with self-fertilized seed. It is not believed that ants pollinate the self-fertile cleistogamous flowers. Beechdrops are used to monitor forest health because of their dependence on their host and the sensitivity to its environment. E. virginiana’s host, beech trees, can advance in a forest faster than E. virginiana is able to.
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Trifolium arvense flowers in early summer and does not require a cold period to induce flowering. Larger plants in good condition may flower for a longer period. In wild populations of Trifolium arvense only plants that are large enough (dry weight >0.01g) tend to produce seeds. The flowers of Trifolium arvense are self-fertilized, but visits by bees provide some opportunity for cross-fertilization.
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Late-acting self-incompatibility (LSI) is the occurrence of self- incompatibility (SI) in flowering plants where pollen tubes from self-pollen successfully reach the ovary, but ovules fail to develop. Mechanisms that might cause late-acting self-incompatibility have yet to be elucidated. One hypothesis is that the occurrence of LSI is caused by early-acting inbreeding depression where the expression of genetic load causes self-fertilized embryos to abort.
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Morning glory vines spread their vegetation and flowers reproduce via mixed mating systems. Peanut plants utilize mixed mating systems, often with cleistogamous flowers. A mixed mating system (in plants), also known as “variable inbreeding” a characteristic of many hermaphroditic seed plants, where more than one means of mating is used. Mixed mating usually refers to the production of a mixture of self-fertilized (selfed) and outbred (outcrossed) seeds.
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It is a form of self-fertilization. In flowering plants, pollen is transferred from a flower to another flower on the same plant, and in animal pollinated systems this is accomplished by a pollinator visiting multiple flowers on the same plant. Geitonogamy is also possible within species that are wind-pollinated, and may actually be a quite common source of self-fertilized seeds in self-compatible species. It also occurs in monoecious gymnosperms.
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Early-acting inbreeding depression is a form of selective embryo abortion that acts on embryos produced by selfing or mating of close relatives. Inbreeding increases genetic homozygosity, allowing selection to elimination recessive, deleterious or lethal alleles (the presence of these deleterious alleles is referred to as genetic load). Thus, selective embryo abortion would be expected to purge genetic load among inbred offspring by aborting those embryos with deleterious genotypes. However, late-acting self-incompatibility also causes abortion of self-fertilized seeds, confounding identification of early-acting inbreeding depression.
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For the field of modifier genes, the most important responses to Fisher's theory came from Haldane. Haldane showed that, contrary to Fisher's argument, despite a decreased intensity of selection for dominance in self-fertilized populations, dominance is often more common in inbred than in outbred plant species. In 1941, Haldane applied the genetic model of modifier genes, which originated from theories of on the evolution of dominance, to phenotypic disease variation in humans. He analyzed data collected by Julia Bell on the heritability of several human diseases with quantitative phenotypes, specifically variation in age of onset.
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Depending upon conditions, garlic mustard flowers either self-fertilize or are cross- pollinated by a variety of insects. Plants from self-fertilized seeds can be genetically identical to their parent plant, enhancing their abilities to thrive in places where their parental genotype can thrive.PCA Alien Plant Working Group – Garlic Mustard (Alliaria petiolata) Close-up of garlic mustard flowers Fruits and seeds Sixty-nine insect herbivores and seven fungi are associated with garlic mustard in Europe. The most important groups of natural enemies associated with garlic mustard were weevils (particularly the genus Ceutorhynchus), leaf beetles, butterflies, and moths, including the larvae of some moth species such as the garden carpet moth.
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Twenty-five diverse corn lines were chosen as the parental lines for the NAM population in order to encompass the remarkable diversity of maize and preserve historic linkage disequilibrium. Each parental line was crossed to the B73 maize inbred (chosen as a reference line due to its use in the public maize sequencing project and wide deployment as one of the most successful commercial inbred lines) to create the F1 population. The F1 plants were then self-fertilized for six generations in order to create a total of 200 homozygous recombinant inbred lines (RILs) per family, for a total of 5000 RILs within the NAM population. The lines are publicly available through the USDA-ARS Maize Stock Center.
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A mutation accumulation experiment conducted by Ruth Shaw and colleagues serves as a good example of a typical MA experiment: the group sought to measure the effects of spontaneous mutations on the reproductive traits of Arabidopsis thaliana. A.thaliana is an ideal candidate for a MA experiment because it is capable of self-fertilization, has a relatively short life cycle (of about 10 weeks), and is a well-studied model organism in plant biology and genetics. Shaw and colleagues established 120 lines of A.thaliana, and advanced each line 17 generations by single-progeny descent: each generation was propagated by a single individual randomly selected from a number of self-fertilized seeds sown. The reproductive traits measured as part of the phenotypic assay included seed number per fruit, fruit number, and reproductive mass (the total mass of fruits and seeds from a single plant).
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