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Apomixis

Apomixis is a form of asexual reproduction in flowering plants in which seeds are produced without meiosis or fertilization, resulting in offspring that are genetically identical clones of the maternal parent.^[1] This process, which modifies key steps of sexual reproduction such as gamete formation and syngamy, occurs in over 400 species across more than 40 angiosperm families, including prominent examples in Asteraceae (e.g., Hieracium and Taraxacum) and Poaceae (e.g., Paspalum).^[1]^[2] Apomixis is broadly classified into two main types based on the origin of the embryo: gametophytic apomixis, in which an unreduced embryo sac develops from a diploid cell and gives rise to a parthenogenetic embryo, and sporophytic apomixis (also called adventitious embryony), in which one or more embryos arise directly from somatic cells of the ovule's nucellus or integument, often alongside a sexually formed zygotic embryo in polyembryonic seeds.^[1] Within gametophytic apomixis, two primary subtypes are distinguished: diplospory, where the megaspore mother cell undergoes an altered meiotic division to produce an unreduced embryo sac, and apospory, where a somatic nucellar cell proliferates mitotically to form the unreduced embryo sac, typically suppressing the sexual pathway.^[1] The genetic control of apomixis involves specific loci and genes that regulate these deviations, such as the LOA locus for apomeiosis and LOP for parthenogenesis in Hieracium, or ASGR-BBML for embryo initiation, often arising through hybridization or polyploidy events.^[1]^[2] Apomixis is typically facultative, meaning apomictic plants can produce some sexual seeds, which allows gene flow and mitigates risks like Muller's ratchet (accumulation of deleterious mutations).^[2] Evolutionarily, apomixis promotes geographical parthenogenesis, enabling rapid colonization of marginal or stressful habitats by providing reproductive assurance without mates, and it is frequently associated with polyploidy.^[2]^[1] In agriculture, apomixis is of high interest for crop improvement, as it could enable the perpetual propagation of hybrid vigor (heterosis) through clonal seeds, reducing the need for annual hybrid reseeding and enhancing food security in crops like rice and maize.^[1]

Fundamentals

Definition

Apomixis, derived from the Greek words "apo" meaning "without" or "away from" and "mixis" meaning "mingling" or "mixing," refers to a form of asexual reproduction in plants. The term was coined by the German botanist Hans Winkler in 1908 to describe the substitution of sexual reproduction by an asexual process without nuclear fusion. Although the concept was formally named in the early 20th century, initial observations of apomictic phenomena date back to the 18th and 19th centuries, with early reports including Citrus species as noted in 1719 and Alchornea ilicifolia in 1839, where seeds developed without apparent fertilization. Detailed studies on dandelions (Taraxacum spp.) followed in the early 20th century.^[3]^[4]^[5]^[6] At its core, apomixis involves the production of seeds containing embryos that are genetically identical to the maternal parent, achieved by bypassing the processes of meiosis and fertilization. In this reproductive strategy, the plant forms viable seeds through mitotic divisions rather than the reductional divisions and syngamy typical of sexual reproduction. This results in clonal propagation via seeds, allowing the perpetuation of favorable genotypes without genetic recombination or variation from paternal contributions.^[7]^[1]^[8] Key characteristics of apomixis include the development of unreduced embryo sacs in the ovule or the direct formation of embryos from somatic (non-reproductive) cells, leading to offspring that are essentially maternal clones. Unlike sexual reproduction, which promotes genetic diversity through meiosis and fertilization, apomixis ensures uniformity but may limit adaptability in changing environments. This process is particularly noted in angiosperms, where it mimics the seed-forming outcome of sexuality while avoiding its genetic mixing.^[1]^[9]^[8] Apomixis fundamentally differs from sexual reproduction in plants by circumventing the processes of meiosis and fertilization, which are central to generating genetic diversity in sexual lineages. In sexual reproduction, meiosis reduces chromosome number in gametes, allowing recombination and independent assortment, while fertilization fuses male and female gametes to restore ploidy and introduce paternal genetic contributions, resulting in variable offspring. By contrast, apomixis produces seeds containing embryos that are genetically identical to the maternal parent, as it avoids meiotic recombination and syngamy, thereby preserving hybrid vigor or specific genotypes across generations without variation.^[10]^[11] While parthenogenesis—the development of an embryo from an unfertilized egg cell—is a key component of many apomictic processes, the two are not synonymous, particularly in plants. Parthenogenesis can occur in both animals and plants, producing embryos that may be haploid or diploid depending on whether meiosis has preceded egg formation, and it does not inherently involve seed production or the avoidance of meiosis. In apomixis, parthenogenesis is typically preceded by apomeiosis, where unreduced (diploid) female gametophytes form without meiosis, ensuring the embryo's diploidy and maternal clonality; this combination allows clonal propagation specifically through seeds, distinguishing apomixis as a plant-specific asexual strategy that integrates parthenogenetic embryo formation with seed dispersal mechanisms. For instance, in species like Hieracium, parthenogenesis alone in mutants leads to embryo development but requires additional genetic elements for full apomixis.^[12]^[11] Apomixis also contrasts with vegetative reproduction, another form of asexual propagation common in plants, by utilizing seeds as the propagule rather than non-reproductive structures. Vegetative reproduction involves cloning via modified organs such as runners, bulbs, tubers, or rhizomes, which lack the protective seed coat, dormancy capabilities, and long-distance dispersal advantages of seeds, limiting its efficiency for colonization. Apomixis, however, leverages the seed's structure for enhanced survival and spread, combining the genetic fidelity of clonality with the ecological benefits of sexual seed production, as seen in apomictic grasses like Paspalum where seeds enable rapid range expansion without reliance on somatic propagules.^[12]^[11] Although apomixis can lead to polyembryony—the formation of multiple embryos within a single seed—this phenomenon is not exclusive to apomixis and serves to highlight their overlap and differences. In apomictic polyembryony, additional embryos often arise from somatic nucellar tissue alongside the parthenogenetic embryo, all clonal to the mother, as in citrus species where nucellar embryony coexists with sexual potential. Sexual polyembryony, however, typically involves cleavage of the zygote or suspensor cells post-fertilization, yielding genetically diverse embryos from a single fertilization event, without the avoidance of meiosis or syngamy. Thus, while polyembryony enhances seedling vigor in both contexts, its apomictic form reinforces clonality, whereas the sexual variant contributes to variability.^[10]^[13]

Types and Mechanisms

Gametophytic Apomixis

Gametophytic apomixis is a form of asexual reproduction in plants where seeds develop from an unreduced female gametophyte, bypassing meiosis and fertilization to produce clonal offspring that preserve the maternal genotype.^[14] In this process, a diploid embryo sac forms without chromosomal reduction, and the unreduced egg cell develops into an embryo through parthenogenesis, while the endosperm arises either autonomously from the central cell or via pseudogamy, where pollination occurs but fertilization of the central cell is required without affecting the egg.^[14] This mechanism contrasts with sexual reproduction by avoiding genetic recombination, enabling the efficient propagation of hybrid vigor in apomictic lineages.^[15] The two primary subtypes of gametophytic apomixis are diplospory and apospory, distinguished by the origin of the unreduced embryo sac. In diplospory, the embryo sac develops directly from the megaspore mother cell (MMC) through restitutional meiosis or complete suppression of meiotic reduction, resulting in a diploid megaspore that undergoes mitotic divisions to form the embryo sac.^[14] Examples include the Taraxacum type, where the MMC undergoes a modified meiosis I followed by equational division, and the Antennaria type, characterized by total meiotic avoidance.^[15] Apospory, conversely, involves the formation of the embryo sac from somatic cells of the nucellus, which differentiate into unreduced cells that mimic gametophytic development without any meiotic involvement.^[14] These nucellar cells undergo mitotic divisions to produce an embryo sac typically containing multiple unreduced cells, including an egg apparatus and central cell.^[15] The developmental process begins with the initiation of the unreduced embryo sac, followed by parthenogenesis where the diploid egg cell divides to form the embryo without sperm fusion, ensuring clonal inheritance.^[14] Endosperm development varies: in autonomous cases, the unreduced central cell proliferates independently to form triploid or higher-ploidy endosperm, as seen in some diplosporous species; in pseudogamous cases, pollen tube entry fertilizes the central cell to trigger endosperm growth, though the embryo remains unfertilized.^[14] This dual potential for endosperm formation allows flexibility in apomictic systems, with examples of both autonomous and pseudogamous forms in each subtype, such as autonomous in diplosporous Taraxacum and aposporous Hieracium, and pseudogamous in aposporous Poaceae.^[15] Gametophytic apomixis is prevalent in certain plant families, notably Asteraceae and Poaceae. In Asteraceae, diplospory occurs in dandelions (Taraxacum officinale), where unreduced embryo sacs lead to seed production without pollinators, facilitating widespread dispersal.^[14] Apospory is documented in hawkweeds (Hieracium spp.), involving nucellar cell-derived embryo sacs that support autonomous endosperm.^[14] In Poaceae, apospory dominates, as in guinea grass (Panicum maximum) and signal grass (Brachiaria brizantha), where somatic nucellar cells form multiple embryo sacs per ovule, enabling clonal propagation in forage crops.^[14] These examples highlight the subtype's role in adapting to diverse ecological niches through stable genotype transmission.^[15]

Sporophytic Apomixis

Sporophytic apomixis, also known as adventitious embryony, is a form of asexual seed production in which embryos develop directly from diploid somatic cells of the ovule, such as those in the nucellus or integument, without undergoing meiosis or fertilization.^[1] This process results in clonal progeny that are genetically identical to the maternal parent, often occurring alongside sexual reproduction within the same ovule.^[7] In the mechanism of sporophytic apomixis, the sexual embryo sac typically forms through standard meiotic processes in the ovule, but surrounding somatic cells proliferate mitotically and differentiate into embryogenic initials that directly form embryos.^[7] These adventitious embryos develop alongside any zygotic embryo and compete for nutrients within the seed, while seed development usually requires fertilization of the polar nuclei in the sexual embryo sac to form functional endosperm.^[1] This leads to polyembryony, where multiple embryos—one sexual and others somatic—develop within a single seed, with the somatic ones dominating in some cases.^[7] A key subtype of sporophytic apomixis is nucellar embryony, where embryos arise specifically from nucellar cells surrounding the embryo sac.^[16] This subtype is genetically controlled by specific loci, such as a dominant locus in citrus involving upregulation of genes like CitRWP, which promotes somatic cell embryogenesis.^[1] Sporophytic apomixis is prevalent in certain plant families, notably Rutaceae, where it occurs in citrus species such as Citrus sinensis (sweet orange), resulting in polyembryonic seeds used in propagation.^[7] It is also found in Mangifera (Anacardiaceae), exemplified by mango (Mangifera indica), where nucellar cells give rise to apomictic embryos that coexist with a potential zygotic one, facilitating clonal reproduction in horticulture.^[17]

Occurrence in Plants

In Non-Flowering Plants

Apomixis in non-flowering plants manifests differently from seed-based forms in angiosperms, often integrating with the distinct alternation of generations characteristic of these lineages, where free-living gametophytes play a prominent role in reproduction. In ferns (Pteridophyta), apomixis primarily involves apogamy, the development of a sporophyte directly from somatic cells of the gametophyte (prothallus) without fertilization, and apospory, the formation of a gametophyte from somatic cells of the sporophyte without meiosis. These processes bypass sexual reproduction, producing unreduced spores via mechanisms like premeiotic endomitosis or meiotic first division restitution, resulting in approximately 32 spores per sporangium instead of the typical 64. About 10% of fern species exhibit obligate apomixis, frequently linked to polyploidy and environmental stressors such as drought, which favor asexual propagation in xeric habitats.^[18]^[19] A notable example is the bracken fern (Pteridium aquilinum), where apogamy is induced in gametophytes by factors including ethylene, light, and sucrose, leading to the formation of triploid sporophytes without gamete fusion. This integration with the fern life cycle allows apomictic lineages to persist in disturbed or arid environments, as unreduced spores maintain maternal genotypes and enable rapid clonal spread. In contrast to angiosperm apomixis, fern apomixis often involves facultative shifts between sexual and asexual phases, with apogamy directly altering the transition from the haploid gametophyte to the diploid sporophyte.^[19]^[20] In bryophytes (mosses, liverworts, and hornworts), apomixis is less common and typically features apospory, where diploid gametophytes develop from sporophyte somatic cells, bypassing meiosis and producing unreduced spores that sustain the gametophyte-dominant life cycle. This results in diploid gametophytes capable of self-fertilization or further aposporous regeneration, though such events are often facultative and environmentally induced. Apogamy, involving sporophyte formation from gametophyte cells without fertilization, is rarer in bryophytes compared to ferns, occurring sporadically in nature and more readily under in vitro conditions, such as in the moss Amblystegium serpens. These processes highlight the gametophyte's central role in bryophyte reproduction, differing from sporophyte-dominant apomixis in vascular plants.^[21]^[22]^[23] Gymnosperms exhibit rare apomixis, primarily through adventitious embryony, a sporophytic mechanism where embryos arise from somatic nucellar tissue within the ovule rather than from fertilized eggs, producing clonal seeds alongside sexual ones. This form of polyembryony occurs sporadically in some conifers, including species of Pinus, where multiple embryos per seed include adventitious ones derived from maternal diploid cells, ensuring genetic uniformity in offspring. Unlike the gametophyte-involved apomixis in ferns and bryophytes, gymnosperm apomixis aligns more closely with angiosperm seed production but remains infrequent, often co-occurring with zygotic embryos in polyembryonic seeds. The alternation of generations in gymnosperms features reduced gametophytes, limiting apomixis to the sporophyte phase and emphasizing its evolutionary divergence from pteridophyte patterns.^[24]^[25]^[26]

In Flowering Plants

Apomixis is documented in over 400 species of flowering plants (angiosperms) across more than 40 families, occurring in approximately 2.2% of angiosperm genera.^[27]^[28] This reproductive strategy is unevenly distributed taxonomically, with the majority of known cases concentrated in a few families, including Asteraceae, Poaceae, and Rosaceae, which account for about 75% of confirmed apomictic examples.^[29] Within these families, apomixis often manifests through gametophytic or sporophytic mechanisms, though the focus here is on its prevalence rather than detailed pathways. In Asteraceae, for instance, numerous genera exhibit apomixis, contributing significantly to the family's diversity of asexual seed production.^[30] Similarly, Poaceae and Rosaceae host prominent apomictic lineages, such as certain grasses and fruits, highlighting the strategy's role in these agriculturally and ecologically important groups. Many apomictic angiosperms are facultative, meaning they can alternate between asexual and sexual reproduction depending on environmental cues or genetic factors, while obligate apomicts rely exclusively on asexual means.^[31] Ecologically, apomixis facilitates rapid colonization and persistence in disturbed or marginal habitats by allowing the production of genetically uniform seeds without the need for pollinators or mates, thereby enhancing dispersal and establishment success. Representative examples include Taraxacum officinale (common dandelion), which thrives in lawns, roadsides, and urban areas through apomictic seed production, and species in the genus Hieracium (hawkweeds), which dominate in meadows and pastures via similar means.^[32] This mode of reproduction supports the invasive potential and resilience of these plants in dynamic environments.

Evolutionary and Genetic Aspects

Evolutionary Origins

Apomixis is widely regarded as a polyphyletic trait, having arisen independently multiple times across plant lineages, often in association with hybridization and polyploidy events that disrupt normal sexual reproduction and promote the formation of unreduced gametes. In angiosperms, these origins are frequently observed in hybrid zones where interspecific crosses lead to genomic instability, facilitating the emergence of apomictic pathways. For instance, diploid hybrids in the genus Boechera and polyploid species in Paspalum demonstrate how such events can trigger apomixis de novo. Recent comparative genomic and transcriptomic studies (as of 2024) further support these polyphyletic origins by revealing shared patterns of meiotic gene repression and transposable element accumulation across independent apomictic lineages.^[11]^[33]^[34] The phylogenetic distribution of apomixis is uneven, with higher prevalence in certain clades such as the Asterids (e.g., Asteraceae, including Hieracium and Taraxacum) and Rosids (e.g., Rosaceae, including Potentilla). It has been documented in approximately 74 of 416 angiosperm families, predominantly in Asteraceae, Poaceae, and Rosaceae, often correlating with polyploid cytotypes. In non-flowering plants, apomixis (manifesting as apogamy) is particularly ancient and recurrent in ferns, with multiple independent origins across lineages like the polystichoid ferns and the genus Pteris, where it appears in 34–39% of species and is concentrated in Paleotropical clades. These fern origins likely date back to early fern diversification, reflecting a long evolutionary history spanning hundreds of millions of years.^[35]^[36] Apomixis confers selective advantages by preserving successful parental genotypes through clonal seed production, providing reproductive assurance in environments with limited mates or pollinators, and enabling rapid range expansion from single individuals, as seen in the colonization of alpine habitats by tetraploid Ranunculus kuepferi. This clonality is especially beneficial in unstable or fragmented habitats, allowing quick establishment of populations. However, it carries disadvantages, including reduced genetic diversity that hampers adaptability to environmental changes or pathogens.^[11]^[33] Evidence for the evolutionary origins of apomixis is primarily indirect, as direct fossil records are scarce due to the subtle developmental nature of the trait; however, ancient asexual lineages in ferns suggest deep-time persistence. Comparative genomic studies provide stronger support, revealing repression of meiotic recombination, accumulation of transposable elements, and modifications in genes regulating sexual reproduction (e.g., loci controlling apomeiosis in Hieracium) in apomictic species compared to sexual relatives.^[37]

Molecular and Genetic Basis

Apomixis is regulated by a complex network of genetic and epigenetic factors that alter reproductive development to bypass meiosis and fertilization. At the core of this process are genes that promote the formation of unreduced gametes and initiate embryo development parthenogenetically. These mechanisms ensure clonal propagation while harnessing elements of the sexual pathway, with studies in model species revealing both conserved and species-specific regulators.^[1] Key genes involved in embryo initiation include APO1, also known as APOLLO, which is exclusively expressed in the ovules of apomictic Boechera species and correlates with apomeiosis through a conserved polymorphism that distinguishes apomictic from sexual alleles. This gene, encoding an Asp-Glu-Asp-Asp-His exonuclease, is upregulated in apomictic ovules and contributes to the avoidance of meiotic recombination, facilitating the production of diploid egg cells capable of direct embryogenesis. Similarly, the ASGR-BBML gene, derived from the apospory-specific genomic region in Pennisetum squamulatum, acts as a BABY BOOM-like transcription factor that induces parthenogenesis by triggering embryo formation from unfertilized egg cells; ectopic expression in sexual pearl millet results in up to 36% parthenogenetic embryos, producing clonal diploid offspring.^[38]^[39]^[40] For the generation of unreduced gametes, the MiMe (mitosis instead of meiosis) system involves coordinated mutations in genes such as SPO11-1, REC8, and OSD1, which replace meiotic divisions with mitotic-like events to produce diploid gametes genetically identical to the parent. In Arabidopsis and rice, triple mutants of these genes (e.g., pair1 rec8 osd1 in rice) yield unreduced female and male gametes without recombination, enabling synthetic apomixis when combined with parthenogenesis triggers; this approach doubles ploidy per generation in MiMe lines, mimicking natural apomeiosis.^[41]^[42] Epigenetic mechanisms, particularly DNA methylation and histone modifications, play crucial roles in suppressing meiosis and stabilizing apomictic development. In Paspalum notatum, high levels of DNA methylation in the apomixis-specific region repress sexual pathways, maintaining parthenogenesis by inactivating meiotic genes, while hypomethylation in species like Cenchrus ciliaris correlates with derepression of apomictic loci. Histone modifications, such as acetylation and methylation, further modulate chromatin accessibility to favor mitotic over meiotic fates, with siRNA pathways reinforcing these changes to prevent recombination and ensure epigenetic inheritance of the apomictic state across generations.^[43]^[1]^[44] The inheritance of apomixis is predominantly controlled by quantitative trait loci (QTLs), often acting in a dominant manner but complicated by linkage to deleterious alleles that accumulate due to clonal reproduction. In Boechera, major QTLs for apomeiosis map to regions with suppressed recombination, including the APOLLO locus, but are associated with hybrid incompatibilities and reduced fertility, posing challenges for introgression into crops. Similarly, in Paspalum, QTLs like QGJ (a MAP3K gene) control apospory, yet tight linkage to repetitive sequences hinders isolation of beneficial traits without co-inherited mutations. Model systems such as Boechera (diploid apomicts) and Paspalum (facultative apomicts) have been instrumental in QTL mapping and gene identification, leveraging their genetic accessibility and proximity to sexual relatives like Arabidopsis to dissect these networks.^[39]^[1]^[45]^[46]

Applications and Implications

Agricultural and Breeding Applications

Apomixis offers significant advantages in agriculture by enabling clonal propagation through seeds, which allows plants to produce offspring genetically identical to the maternal parent without the need for sexual reproduction. This process preserves desirable traits across generations, particularly in hybrid crops where it fixes heterosis, or hybrid vigor, ensuring that subsequent progeny maintain the enhanced yield, uniformity, and disease resistance observed in the first filial (F1) generation. Unlike traditional hybrid breeding, where heterosis is lost due to segregation in subsequent generations, apomictic seeds generate uniform clonal lines, reducing the costs and labor associated with annual hybrid seed production.^[47] In major staple crops, apomixis holds substantial potential for improving breeding efficiency. For instance, introducing apomixis into rice, maize, and wheat could stabilize superior hybrid genotypes, allowing farmers to replant seeds year after year while retaining high productivity. These cereals, which lack natural apomixis, represent key targets for such applications due to their global importance and the economic burden of hybrid seed systems. Natural apomixis is already exploited in forage grasses like Brachiaria, where it facilitates the clonal propagation of high-yielding cultivars suited to tropical pastures, supporting livestock production across approximately 25 million hectares in Latin America.^[47]^[11] Historical observations of apomixis in citrus cultivation date back to the early 20th century, when it was recognized for enabling true-to-type propagation through nucellar embryony, a form of sporophytic apomixis. Nurseries utilized this trait to produce uniform rootstock seedlings genetically identical to the mother plant, facilitating reliable clonal dissemination of varieties without the variability introduced by sexual seeds. This approach addressed challenges in citrus breeding, where polyembryonic seeds containing both sexual and asexual embryos allowed selection of nucellar types for consistent orchard establishment.^[48] Despite these benefits, apomixis in breeding faces notable challenges, including its frequent linkage to sterility or reduced seed set, which can limit reproductive success in crop populations. In many natural apomicts, the trait is associated with genetic factors that impair male or female gamete function, leading to lower fertility and complicating introgression into elite sexual lines. Breeding strategies aim to decouple apomixis from these negative effects through selective hybridization and genetic mapping, focusing on isolating the core components of asexual seed formation while restoring fertility in hybrid backgrounds.^[49]

Recent Advances in Research

Recent advances in synthetic apomixis have focused on engineering the avoidance of meiosis combined with the induction of parthenogenesis to produce clonal seeds in crops. In rice, researchers have developed models that achieve over 99% clonal seed production by inactivating key meiotic genes (MiMe system) and driving parthenogenetic embryo formation through targeted expression of genes like BABY BOOM1 (BBM1) or OsWUS.^[50]^[51] These approaches, refined since 2024, enable the fixation of hybrid vigor without repeated crossing, as demonstrated in multiple hybrid rice varieties.^[52] Key studies from 2025 highlight progress in integrating doubled haploid technology with synthetic apomixis for hybrid crops. A bioRxiv preprint reported a system combining clonal gametogenesis with parthenogenesis in rice hybrids, yielding >99% efficient apomixis while maintaining near-normal seed set and fertility across generations.^[50] Similarly, a Nature article detailed gene-edited "sexless" seeds in crops like rice and sorghum, where CRISPR-mediated mutations bypass fertilization to generate maternal clones, potentially transforming farming by reducing seed production costs.^[53] These innovations build on earlier MiMe engineering but emphasize scalability in hybrids.^[42] In non-model organisms, apomixis research has expanded to applications in aquaculture, particularly kelp. A 2025 review outlined apomixis mechanisms in brown algae like Saccharina species, where aposporous reproduction allows clonal propagation of elite strains for faster genetic improvement in farming.^[54] Molecular tools such as CRISPR-Cas9 have been adapted for trait fixation in these systems, enabling precise editing to preserve desirable aquaculture traits like growth rate without sexual recombination.^[54]^[55] These developments promise to revolutionize hybrid seed production by enabling perennial propagation of superior genotypes, potentially increasing yields and reducing breeding timelines in staple crops.^[53] However, ethical concerns around biodiversity loss from widespread clonality and ecological risks of uniform populations in agriculture remain under discussion. In November 2025, further progress included the synthetic induction of apomixis in two sorghum hybrids, allowing maintenance of clonal hybrid seeds across multiple generations with preserved yield, and a high-throughput sequencing screen to identify apomixis traits in diverse plant species.^[56]^[57]

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May 18, 2023 · Another mode of apomixis, classified as sporophytic, is adventitious embryony, in which embryos develop directly from somatic cells of the ...<|control11|><|separator|>
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Introgression of apomixis into sexual species is inhibited by mentor ...
Apr 22, 2009 · This feature may allow for rapid colonization of novel or moderately disturbed habitats, such as meadows (Paun et al., 2006a; Hörandl and ...Missing: enables | Show results with:enables
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Sep 13, 2024 · Both gametophytic and sporophytic apomixis results in clonal offspring, but often remains facultative, i.e. in the same generation the plant ...
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assessing the impact of apomixis in the fern genus Pteris - PMC
Apomixis (asexual reproduction by seed, spore, or egg) has evolved repeatedly across the tree of life. Studies of animals and angiosperms show that ...
[35]
Trends in Apomixis Research: The 10 Most Cited Research Articles ...
May 2, 2022 · One of the milestones in the genetic study of apomixis is represented by the identification of the DYAD/SWITCH1 (SWI1) locus, a regulator of ...
[36]
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The Boechera Genus as a Resource for Apomixis Research - Frontiers
In this review, we discuss the advantages of the Boechera genus to study apomixis, consider its modes of reproduction as well as the inheritance and possible ...Abstract · Population Genetic Studies in... · Inheritance and Genetic... · ConclusionMissing: APO1 | Show results with:APO1
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A parthenogenesis gene of apomict origin elicits embryo formation ...
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Turning Meiosis into Mitosis | PLOS Biology - Research journals
As a consequence, MiMe plants produced diploid male and female gametes that are genetically identical to their parent, and ploidy doubles at each generation.
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High-frequency synthetic apomixis in hybrid rice - Nature
Dec 27, 2022 · The MiMe system to make unreduced gametes was originally developed in Arabidopsis. Thus, the results from this study could have wider ...
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methylation status analysis of the apomixis-specific region in ...
Sep 1, 2014 · The results suggested that factors controlling repression of parthenogenesis might be inactivated in apomictic Paspalum by DNA methylation.
[42]
Apomixis: oh, what a tangled web we have! - PMC - PubMed Central
Mar 31, 2023 · Apomixis is a complex evolutionary trait with many possible origins. Here we discuss various clues and causes, ultimately proposing a model.
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Structural variation and parallel evolution of apomixis in citrus during ...
Citrus cross-breeding has been hampered by the presence of apomixis, an asexual form of seed formation that can limit the recovery of sexual progeny [9].
[44]
How to Become an Apomixis Model - PubMed Central - NIH
The two main Paspalum species used as models for apomixis research, P. notatum and P. simplex, form agamic complexes made up of diploid sexual and autopolyploid ...
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Apomixis and strategies to induce apomixis to preserve hybrid vigor ...
Apomixis has the potential to preserve hybrid vigor for multiple generations in economically important plant genotypes.
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Citrus Polyembryony - IntechOpen
Successfully harnessing apomixis for citrus propagation requires ... It has been used in nurseries since the first decades of the 20th century to identify hybrids ...
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Apomixis and strategies to induce apomixis to preserve hybrid vigor ...
Apomixis has the potential to preserve hybrid vigor for multiple generations in economically important plant genotypes. The evolution and genetics of asexual ...
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Fixing Hybrid Rice: >99% Efficient Apomixis with Near-Normal Seed ...
Oct 17, 2025 · When combined with clonal gametogenesis, this system achieved nearly complete synthetic apomixis, with clonal seed production rates exceeding 99 ...Missing: doubled | Show results with:doubled
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Researchers Establish New Synthetic Apomixis System with Rice ...
Oct 22, 2024 · In this study, researchers found that the rice endogenous gene OsWUS could be regulated to induce apomixis and achieve clonal seed production ...Missing: engineering avoidance
[51]
Is this the future of food? 'Sexless' seeds that could transform farming
Sep 2, 2025 · Scientists are tinkering with plant genes to create crops that seed their own clones, with a host of benefits for farmers.
[52]
Apomixis in kelp genetic improvement: Practices, challenges, and ...
Mar 15, 2025 · Apomixis is a reproductive mode allowing organisms to produce seeds without meiosis and fertilization. Apomictic plants produce genetically ...
[53]
CRISPR/Cas Technology Revolutionizes Crop Breeding - PMC
Apomixis has the potential to allow offspring to retain valuable traits ... Recently, genome editing-mediated apomixis technology has realized heterosis fixation ...
[54]
Widespread application of apomixis in agriculture requires further ...
Sep 20, 2024 · Apomixis is generally divided into two major types depending on the origin of the embryo: sporophytic and gametophytic apomixis. These two ...