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Journal articles on the topic 'Polyploidy'
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1
Li, Xiaoying, Luyue Zhang, Xiaochun Wei, Tanusree Datta, Fang Wei, and Zhengqing Xie. "Polyploidization: A Biological Force That Enhances Stress Resistance." International Journal of Molecular Sciences 25, no. 4 (February 6, 2024): 1957. http://dx.doi.org/10.3390/ijms25041957.
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Organisms with three or more complete sets of chromosomes are designated as polyploids. Polyploidy serves as a crucial pathway in biological evolution and enriches species diversity, which is demonstrated to have significant advantages in coping with both biotic stressors (such as diseases and pests) and abiotic stressors (like extreme temperatures, drought, and salinity), particularly in the context of ongoing global climate deterioration, increased agrochemical use, and industrialization. Polyploid cultivars have been developed to achieve higher yields and improved product quality. Numerous studies have shown that polyploids exhibit substantial enhancements in cell size and structure, physiological and biochemical traits, gene expression, and epigenetic modifications compared to their diploid counterparts. However, some research also suggested that increased stress tolerance might not always be associated with polyploidy. Therefore, a more comprehensive and detailed investigation is essential to complete the underlying stress tolerance mechanisms of polyploids. Thus, this review summarizes the mechanism of polyploid formation, the polyploid biochemical tolerance mechanism of abiotic and biotic stressors, and molecular regulatory networks that confer polyploidy stress tolerance, which can shed light on the theoretical foundation for future research.
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Ebinuma, Hiroyasu, Masahiko Kobayashi, Jun Kobayashi, Toru Shimada, and Narumi Yoshitake. "The detection of mosaics and polyploids in a hereditary mosaic strain of the silk moth, Bombyx mori, using egg colour mutants." Genetical Research 51, no. 3 (June 1988): 223–29. http://dx.doi.org/10.1017/s0016672300024320.
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SummaryTo analyze abnormal fertilization in a hereditary mosaic strain (mo/mo) of Bombyx mori, the percentages of diploidy mosaic, polyploidy mosaic and polyploid eggs in a batch were estimated by using egg colour mutants (pe re). Among 48 890 eggs from crosses of pe + / + re, mo/mo females with pe re/pe re males, 9409 abnormal eggs were obtained; 4472 of them were diploidy mosaics (red-white eggs), 4038 were polyploids (black eggs) and 899 were polyploidy mosaics (566 black-white, 256 black-red and 77 black-white-red eggs). The total number of diploidy mosaic eggs was approximately equal to that of polyploid eggs. A significant correlation was detected between the diploidy mosaic and polyploid egg ratios within a batch. This suggests that diploidy mosaics are produced by double fertilization in which two genetically non-identical egg nuclei are fertilized in turn by a sperm, and polyploids are formed by the fertilization of a diploid, non-disjunctive egg nucleus gamete by a single sperm. Our results also indicated the presence of common factors modifying both mosaic and polyploid frequency. The concordance of the observed ratio of polyploidy mosaic eggs (1·84%) with the expected value (diploidy mosaic ratio × polyploidy ratio × 2 = 1·83%) suggests that the formation of mosaics occurs independently of the formation of polyploids in this abnormal fertilization process. We point out that it is necessary to modify Goldschmidt & Katsuki's general model to explain abnormal fertilization, and we propose several possible models.
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Tiwana, Anupreet Singh, Siva Prathap Thummalakunta, Saurabh Gupta, Vijay Singh, and Ramesh Chand Kataria. "The Influence of Geographical Factors on Polyploidy in Angiosperms with Cartographic Evidence from the Northwestern Himalayas: A Review." Nature Environment and Pollution Technology 22, no. 1 (March 2, 2023): 293–301. http://dx.doi.org/10.46488/nept.2023.v22i01.029.
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The review paper comprised the impact of geographical and environmental factors on polyploidy and vice versa. The review covers different effects of geographical factors, like spatial isolation, altitude, and local climate on polyploidy, and the behavior of polyploid(s) in abiotic factors, such as temperature and light with a few examples of northwest Himalayas. The paper concludes that polyploid plants behave differently in environmental conditions, as polyploids are more prominent in higher altitudes, colder environments, and nutrient-rich soil than diploid progenitors, but have a mixed distribution in different geographical conditions. Further, polyploidy is more common among perennials than annuals, while niche differentiation depends more on the local environment. The virtual case study results from North and North Western India have been shown with the help of ArcGIS online software. The scrutiny of spatial distribution on maps highlights the fact that polyploidy is still a complex research puzzle with interesting perspectives.
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Vilcherrez-Atoche, Joe Abdul, Carla Midori Iiyama, and Jean Carlos Cardoso. "Polyploidization in Orchids: From Cellular Changes to Breeding Applications." Plants 11, no. 4 (February 9, 2022): 469. http://dx.doi.org/10.3390/plants11040469.
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Polyploidy occurs naturally in plants through cell division errors or can artificially be induced by antimitotic agents and has ecological effects on species adaptation, evolution, and development. In agriculture, polyploidy provides economically improved cultivars. Furthermore, the artificial induction of polyploids increases the frequency; thus, it accelerates obtaining polyploid plants used in breeding programs. This is the reason for its use in developing many crops of economic interest, as is the case of orchids in the flower market. Polyploidy in ornamental plants is mainly associated with flowers of larger size, fragrance, and more intense coloring when compared to naturally diploid plants. Currently, orchids represent the largest flower market worldwide; thus, breeding programs aim to obtain flowers with the larger size, durability, intense colors, and resistance to pathogens. Furthermore, orchid hybridization with polyploidy induction has been used to produce improved hybrid cultivars. Thus, the objective of this review was to compile information regarding the natural occurrence, importance, and methods of induction of polyploidy in orchids. The study also summarizes the significance of polyploids and techniques associated with artificially inducing polyploidy in different orchids of commercial relevance.
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Mezzasalma, Marcello, Elvira Brunelli, Gaetano Odierna, and Fabio Maria Guarino. "Evolutionary and Genomic Diversity of True Polyploidy in Tetrapods." Animals 13, no. 6 (March 12, 2023): 1033. http://dx.doi.org/10.3390/ani13061033.
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True polyploid organisms have more than two chromosome sets in their somatic and germline cells. Polyploidy is a major evolutionary force and has played a significant role in the early genomic evolution of plants, different invertebrate taxa, chordates, and teleosts. However, the contribution of polyploidy to the generation of new genomic, ecological, and species diversity in tetrapods has traditionally been underestimated. Indeed, polyploidy represents an important pathway of genomic evolution, occurring in most higher-taxa tetrapods and displaying a variety of different forms, genomic configurations, and biological implications. Herein, we report and discuss the available information on the different origins and evolutionary and ecological significance of true polyploidy in tetrapods. Among the main tetrapod lineages, modern amphibians have an unparalleled diversity of polyploids and, until recently, they were considered to be the only vertebrates with closely related diploid and polyploid bisexual species or populations. In reptiles, polyploidy was thought to be restricted to squamates and associated with parthenogenesis. In birds and mammals, true polyploidy has generally been considered absent (non-tolerated). These views are being changed due to an accumulation of new data, and the impact as well as the different evolutionary and ecological implications of polyploidy in tetrapods, deserve a broader evaluation.
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Mo, Lan, Junhao Chen, Xiongzhen Lou, Qiangwei Xu, Renhui Dong, Zaikang Tong, Huahong Huang, and Erpei Lin. "Colchicine-Induced Polyploidy in Rhododendron fortunei Lindl." Plants 9, no. 4 (March 31, 2020): 424. http://dx.doi.org/10.3390/plants9040424.
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Polyploidy in Rhododendron fortunei has great potential to improve its horticultural and commercial value, and to also meet market demands. In this study, a feasible method for polyploid induction in R. fortunei via colchicine treatment was established, and the obtained polyploid plants were identified and characterized. As a result, the stem bases of tissue-cultured plantlets treated with 0.1% colchicine for 24 h showed the highest polyploid induction with a rate of 36.67%. By flow cytometric analysis, 69 tetraploids and 29 octoploids were identified in the regenerated plants that were examined. Phenotypic analysis indicated that the leaves of tetraploid and octoploid plants were smaller, rounder and thicker with more abundant and longer epidermal hairs than those of diploids. Furthermore, the stomata of polyploids were larger and sparser than those of diploids. An increase in chlorophyll content was also detected in polyploids, which resulted in darker green leaves. In conclusion, our study established an effective method to induce polyploidy in R. fortunei, which could be used to develop new genetic resources for breeding R. fortunei and other Rhododendron species in the future.
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Chao, Yi-Shan, Ho-Yih Liu, Yu-Chung Chiang, and Wen-Liang Chiou. "Polyploidy and Speciation in Pteris (Pteridaceae)." Journal of Botany 2012 (March 14, 2012): 1–7. http://dx.doi.org/10.1155/2012/817920.
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The highest frequency of polyploidy among plants is considered to occur in the Pteridophytes. In this study, we focused on polyploidy displayed by a specific fern taxon, the genus Pteris L. (Pteridaceae), comprising over 250 species. Cytological data from 106 Pteris species were reviewed. The base number of chromosomes in Pteris is 29. Polyploids are frequently found in Pteris, including triploids, tetraploids, pentaploids, hexaploids, and octoploids. In addition, an aneuploid species, P. deltodon Bak., has been recorded. Furthermore, the relationship between polyploidy and reproductive biology is reviewed. Among these 106 Pteris species, 60% exhibit polyploidy: 22% show intraspecific polyploidy and 38% result from polyploid speciation. Apogamous species are common in Pteris. Diploids are the most frequent among Pteris species, and they can be sexual or apogamous. Triploids are apogamous; tetraploids are sexual or apogamous. Most Pteris species have one to two ploidy levels. The diverse ploidy levels suggest that these species have a complex evolutionary history and their taxonomic problems require further clarification.
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Rauf, Saeed, Rodomiro Ortiz, Dariusz P. Malinowski, Wellington Ronildo Clarindo, Wardah Kainat, Muhammad Shehzad, Ummara Waheed, and Syed Wasim Hassan. "Induced Polyploidy: A Tool for Forage Species Improvement." Agriculture 11, no. 3 (March 4, 2021): 210. http://dx.doi.org/10.3390/agriculture11030210.
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Polyploidy means having more than two basic sets of chromosomes. Polyploid plants may be artificially obtained through chemical, physical and biological (2n gametes) methods. This approach allows an increased gene scope and expression, thus resulting in phenotypic changes such as yield and product quality. Nonetheless, breeding new cultivars through induced polyploidy should overcome deleterious effects that are partly contributed by genome and epigenome instability after polyploidization. Furthermore, shortening the time required from early chromosome set doubling to the final selection of high yielding superior polyploids is a must. Despite these hurdles, plant breeders have successfully obtained polyploid bred-germplasm in broad range of forages after optimizing methods, concentration and time, particularly when using colchicine. These experimental polyploids are a valuable tool for understanding gene expression, which seems to be driven by dosage dependent gene expression, altered gene regulation and epigenetic changes. Isozymes and DNA-based markers facilitated the identification of rare alleles for particular loci when compared with diploids, and also explained their heterozygosity, phenotypic plasticity and adaptability to diverse environments. Experimentally induced polyploid germplasm could enhance fresh herbage yield and quality, e.g., leaf protein content, leaf total soluble solids, water soluble carbohydrates and sucrose content. Offspring of experimentally obtained hybrids should undergo selection for several generations to improve their performance and stability.
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Martinez-Perez, Enrique, Peter J. Shaw, and Graham Moore. "Polyploidy Induces Centromere Association." Journal of Cell Biology 148, no. 2 (January 24, 2000): 233–38. http://dx.doi.org/10.1083/jcb.148.2.233.
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Many species exhibit polyploidy. The presence of more than one diploid set of similar chromosomes in polyploids can affect the assortment of homologous chromosomes, resulting in unbalanced gametes. Therefore, a mechanism is required to ensure the correct assortment and segregation of chromosomes for gamete formation. Ploidy has been shown to affect gene expression. We present in this study an example of a major effect on a phenotype induced by ploidy within the Triticeae. We demonstrate that centromeres associate early during anther development in polyploid species. In contrast, centromeres in diploid species only associate at the onset of meiotic prophase. We propose that this mechanism provides a potential route by which chromosomes can start to be sorted before meiosis in polyploids. This explains previous reports indicating that meiotic prophase is shorter in polyploids than in their diploid progenitors. Even artificial polyploids exhibit this phenotype, suggesting that the mechanism must be present in diploids, but only expressed in the presence of more than one diploid set of chromosomes.
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Thomas, Gregg W. C., S. Hussain Ather, and Matthew W. Hahn. "Gene-Tree Reconciliation with MUL-Trees to Resolve Polyploidy Events." Systematic Biology 66, no. 6 (April 28, 2017): 1007–18. http://dx.doi.org/10.1093/sysbio/syx044.
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Abstract Polyploidy can have a huge impact on the evolution of species, and it is a common occurrence, especially in plants. The two types of polyploids—autopolyploids and allopolyploids—differ in the level of divergence between the genes that are brought together in the new polyploid lineage. Because allopolyploids are formed via hybridization, the homoeologous copies of genes within them are at least as divergent as orthologs in the parental species that came together to form them. This means that common methods for estimating the parental lineages of allopolyploidy events are not accurate, and can lead to incorrect inferences about the number of gene duplications and losses. Here, we have adapted an algorithm for topology-based gene-tree reconciliation to work with multi-labeled trees (MUL-trees). By definition, MUL-trees have some tips with identical labels, which makes them a natural representation of the genomes of polyploids. Using this new reconciliation algorithm we can: accurately place allopolyploidy events on a phylogeny, identify the parental lineages that hybridized to form allopolyploids, distinguish between allo-, auto-, and (in most cases) no polyploidy, and correctly count the number of duplications and losses in a set of gene trees. We validate our method using gene trees simulated with and without polyploidy, and revisit the history of polyploidy in data from the clades including both baker’s yeast and bread wheat. Our re-analysis of the yeast data confirms the allopolyploid origin and parental lineages previously identified for this group. The method presented here should find wide use in the growing number of genomes from species with a history of polyploidy. [Polyploidy; reconciliation; whole-genome duplication.]
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Banjade, Gaurave, Goma Chaudhari, Asmita Mahato, and Shreesha Uprety. "POLYPLOIDY BREEDING IN AGRICULTURE: AN OVERVIEW." Reviews In Food And Agriculture 4, no. 1 (January 16, 2023): 25–27. http://dx.doi.org/10.26480/rfna.01.2023.25.27.
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Polyploid is a condition where the chromosomes are more than complete sets. The chromosome sets can vary owing to both natural and man-made processes. In artificial process, the mostly used chemical is colchicine which a toxic alkaloid extracted from Colchicum autumnale which was first discovered in 1937. Polyploids helps to increase the size of the cells i.e., giggas. Despite being a technique for creating variance, it is not becoming more popular. This research examines several facets of polyploidy breeding by examining various published works. They outperform natural diploids in terms of high yield, resilience to biotic and abiotic factors, and having better vigor. Irregular fruits, higher percentage of water, sterility made the polyploidy application concentrated only to vegetatively propagated and seedless plants. Although using polyploidy in breeding programs is not a novel method, it is continuously being investigated for potential improvements.
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Bomblies, Kirsten. "When everything changes at once: finding a new normal after genome duplication." Proceedings of the Royal Society B: Biological Sciences 287, no. 1939 (November 18, 2020): 20202154. http://dx.doi.org/10.1098/rspb.2020.2154.
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Whole-genome duplication (WGD), which leads to polyploidy, is implicated in adaptation and speciation. But what are the immediate effects of WGD and how do newly polyploid lineages adapt to them? With many studies of new and evolved polyploids now available, along with studies of genes under selection in polyploids, we are in an increasingly good position to understand how polyploidy generates novelty. Here, I will review consistent effects of WGD on the biology of plants, such as an increase in cell size, increased stress tolerance and more. I will discuss how a change in something as fundamental as cell size can challenge the function of some cell types in particular. I will also discuss what we have learned about the short- to medium-term evolutionary response to WGD. It is now clear that some of this evolutionary response may ‘lock in’ traits that happen to be beneficial, while in other cases, it might be more of an ‘emergency response’ to work around physiological changes that are either deleterious, or cannot be undone in the polyploid context. Yet, other traits may return rapidly to a diploid-like state. Polyploids may, by re-jigging many inter-related processes, find a new, conditionally adaptive, normal.
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Williams, Joseph H., and Paulo E. Oliveira. "For things to stay the same, things must change: polyploidy and pollen tube growth rates." Annals of Botany 125, no. 6 (January 20, 2020): 925–35. http://dx.doi.org/10.1093/aob/mcaa007.
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Abstract Background and Aims Pollen tube growth rate (PTGR) is an important single-cell performance trait that may evolve rapidly under haploid selection. Angiosperms have experienced repeated cycles of polyploidy (whole genome duplication), and polyploidy has cell-level phenotypic consequences arising from increased bulk DNA amount and numbers of genes and their interactions. We sought to understand potential effects of polyploidy on several underlying determinants of PTGR – pollen tube dimensions and construction rates – by comparing diploid–polyploid near-relatives in Betula (Betulaceae) and Handroanthus (Bignoniaceae). Methods We performed intraspecific, outcrossed hand-pollinations on pairs of flowers. In one flower, PTGR was calculated from the longest pollen tube per time of tube elongation. In the other, styles were embedded in glycol methacrylate, serial-sectioned in transverse orientation, stained and viewed at 1000× to measure tube wall thicknesses (W) and circumferences (C). Volumetric growth rate (VGR) and wall production rate (WPR) were then calculated for each tube by multiplying cross-sectional tube area (πr2) or wall area (W × C), by the mean PTGR of each maternal replicate respectively. Key Results In Betula and Handroanthus, the hexaploid species had significantly wider pollen tubes (13 and 25 %, respectively) and significantly higher WPRs (22 and 18 %, respectively) than their diploid congeners. PTGRs were not significantly different in both pairs, even though wider polyploid tubes were predicted to decrease PTGRs by 16 and 20 %, respectively. Conclusions The larger tube sizes of polyploids imposed a substantial materials cost on PTGR, but polyploids also exhibited higher VGRs and WPRs, probably reflecting the evolution of increased metabolic activity. Recurrent cycles of polyploidy followed by genome reorganization may have been important for the evolution of fast PTGRs in angiosperms, involving a complex interplay between correlated changes in ploidy level, genome size, cell size and pollen tube energetics.
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Gorla, Giridhar R., Harmeet Malhi, and Sanjeev Gupta. "Polyploidy associated with oxidative injury attenuates proliferative potential of cells." Journal of Cell Science 114, no. 16 (August 15, 2001): 2943–51. http://dx.doi.org/10.1242/jcs.114.16.2943.
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Polyploid cells are encountered ubiquitously but the biological significance of polyploidy is unclear. In view of their extensive capacity for regeneration, hepatocytes offer excellent systems for analyzing growth control mechanisms. We isolated hepatocytes from adult rats with and without two-third partial hepatectomy, which induces hepatic polyploidy. Polyploid hepatocytes showed evidence for oxidative injury with antioxidant depletion, lipid peroxidation and 8-hydroxy-adducts of guanine in nuclear DNA. Liver repopulation assays in intact animals showed markedly decreased replication capacity in polyploid hepatocytes. Recapitulation of polyploidy in cultured hepatocytes established that mitogenic stimulation in the presence of oxidative DNA injury was capable of inducing polyploidy. The findings provide novel frameworks in the context of polyploidy for understanding tissue development, regeneration and oncogenesis.
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Yan, Zhi, Zhen Cao, and Luay Nakhleh. "Polyphest: fast polyploid phylogeny estimation." Bioinformatics 40, Supplement_2 (September 1, 2024): ii20—ii28. http://dx.doi.org/10.1093/bioinformatics/btae390.
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Abstract Motivation Despite the widespread occurrence of polyploids across the Tree of Life, especially in the plant kingdom, very few computational methods have been developed to handle the specific complexities introduced by polyploids in phylogeny estimation. Furthermore, methods that are designed to account for polyploidy often disregard incomplete lineage sorting (ILS), a major source of heterogeneous gene histories, or are computationally very demanding. Therefore, there is a great need for efficient and robust methods to accurately reconstruct polyploid phylogenies. Results We introduce Polyphest (POLYploid PHylogeny ESTimation), a new method for efficiently and accurately inferring species phylogenies in the presence of both polyploidy and ILS. Polyphest bypasses the need for extensive network space searches by first generating a multilabeled tree based on gene trees, which is then converted into a (uniquely labeled) species phylogeny. We compare the performance of Polyphest to that of two polyploid phylogeny estimation methods, one of which does not account for ILS, namely PADRE, and another that accounts for ILS, namely MPAllopp. Polyphest is more accurate than PADRE and achieves comparable accuracy to MPAllopp, while being significantly faster. We also demonstrate the application of Polyphest to empirical data from the hexaploid bread wheat and confirm the allopolyploid origin of bread wheat along with the closest relatives for each of its subgenomes. Availability and implementation Polyphest is available at https://github.com/NakhlehLab/Polyphest.
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Keeler, Kathleen H. "Distribution of polyploid variation in big bluestem (Andropogon gerardii, Poaceae) across the tallgrass prairie region." Genome 33, no. 1 (February 1, 1990): 95–100. http://dx.doi.org/10.1139/g90-015.
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The objective of this research was to describe the distribution of polyploid cytotypes of the grass big bluestem (Andropogon gerardii Vitman) along an east–west transect across the tallgrass prairie region, as an integral part of understanding the function of intraspecific polyploid polymorphism. Andropogon gerardii shows intraspecific variation in amount of nuclear DNA as a result of intraspecific polyploidy. Nearly 600 plants from 15 prairies in 5 states were collected and nuclear DNA was determined by flow cytometry. In the eastern part of the tallgrass prairie region, higher polyploids were rarely found. However, at the western edge of the tallgrass prairie, west of the Missouri River, plants with high nuclear DNA values comprised about half of the plants sampled and in one native prairie formed 82% of the population. Although big bluestem is historically the dominant grass throughout this region, it is extremely variable only on the western extreme of region.Key words: polyploidy, polymorphism, big bluestem, Poaceae, Andropogon gerardii, tallgrass prairie.
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Ohri, Deepak. "Polyploidy in Gymnosperms-A Reappraisal." Silvae Genetica 70, no. 1 (January 1, 2021): 22–38. http://dx.doi.org/10.2478/sg-2021-0003.
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Abstract Recent polyploidy in gymnosperms is unusually scarce being present in only 9.80 % of the 714 taxa studied cytologically. Polyploid forms are represented by sporadic seedlings and individual trees, intraspecific polyploidy in cultivation or in wild and entirely polyploid species and genera. Polyploidy shows a non-random distribution in different genera being mostly prevalent in Ephedra and Juniperus, besides the classic examples of Sequoia and Fitzroya. Remarkably, both Ephedra and Juniperus show adaptive radiation by interspecific hybridization followed by polyploidy while in Ginkgo viable polyploid cytotypes are found in cultivation. Induced polyploidy has not provided any tangible results in the past but recent attempts on certain genera of Cupressaceae hold some promise of producing cultivars for horticulture trade. Lastly, various evidences derived from cytological analysis, fossil pollen, guard cells and comparative genomic studies indicating the occurrence of paleopolyploidy have been discussed.
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Mayrose, Itay, Shing H. Zhan, Carl J. Rothfels, Karen Magnuson-Ford, Michael S. Barker, Loren H. Rieseberg, and Sarah P. Otto. "Recently Formed Polyploid Plants Diversify at Lower Rates." Science 333, no. 6047 (August 18, 2011): 1257. http://dx.doi.org/10.1126/science.1207205.
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Polyploidy, the doubling of genomic content, is a widespread feature, especially among plants, yet its macroevolutionary impacts are contentious. Traditionally, polyploidy has been considered an evolutionary dead end, whereas recent genomic studies suggest that polyploidy has been a key driver of macroevolutionary success. We examined the consequences of polyploidy on the time scale of genera across a diverse set of vascular plants, encompassing hundreds of inferred polyploidization events. Likelihood-based analyses indicate that polyploids generally exhibit lower speciation rates and higher extinction rates than diploids, providing the first quantitative corroboration of the dead-end hypothesis. The increased speciation rates of diploids can, in part, be ascribed to their capacity to speciate via polyploidy. Only particularly fit lineages of polyploids may persist to enjoy longer-term evolutionary success.
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HIEU, P. V. "AGRICULTURAL DEVELOPMENT BASED ON POLYPLOIDIZATION: A PERSPECTIVE CONTRIBUTION OF MINOR CROPS." SABRAO Journal of Breeding and Genetics 54, no. 5 (December 31, 2022): 1125–40. http://dx.doi.org/10.54910/sabrao2022.54.5.14.
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Polyploidization is commonly known to become a vital process to succeed in developing potential crops. In the plant kingdom, the polyploids, i.e., aneuploidy and polyploidy, are generally developed through sexual and asexual pathways, resulting in totally increasing biomass, phytochemical compounds, and adaptation to detrimental environment. For more precision, thousands of polyploidy plant species adapted to various climatic and topographic conditions through genomic evolution. Autopolyploid, allopolyploid, and aneuploidy, as well as, different levels of ploidy are simply found in vegetables, such as, potatoes, and among fruits, i.e., bananas, watermelon, and so on. Contrastingly, in mammals, polyploidization causes congenital diseases and pregnancy loss, especially in human beings. This review article will first describe polyploidization in plants and then enumerate the advantages of its beneficial effects that are more valuable. The paper also intends to introduce new knowledge on polyploidization in crop breeding. Thus, it has further mentioned the polyploid like aneuploidy and polyploidy in a perspective contribution of minor crops in plant kingdoms and their beneficial and detrimental effects in the development of crop strategies.
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Omere, E. A., C. N. C. Nwaoguala, and T. O. Emede. "Polyploidy and its relevance in crop improvement." Nigerian Journal of Biotechnology 39, no. 2 (February 15, 2023): 9–19. http://dx.doi.org/10.4314/njb.v39i2.2.
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Many areas of research in crop production have been geared towards crop improvement and increased yield. Crop improvement include but not restricted to; plant introduction and acclimatization, domestication, ploidy manipulation (polyploidization), recombinant DNA technology, crossing for superior selection (cultivar development), molecular genetics, etc. Polyploidy is a condition where the genome of an organism has more than the usual number of complete sets of chromosomes and the product of this phenomenon is called a Polyploid. Polyploidy occurs naturally, and can be induced chemically using antimitotic agents or physically using protoplast fusion and temperature shock. It is mostly artificially induced through a process called polyploidization. Polyploids are more advantageous in important plant attributes than the regular diploid. Relative success has been reported in the application of polyploidization for crop improvement which resulted chiefly in increased amount of beneficial secondary metabolites (phytochemicals), larger stomata and leaves,improved adaptation to stress and unfavourable conditions, to mention but a few. Therefore, it is imperative to state that polyploidy is an area of research that has been and will continually be deployed in crop improvement .
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Isnawati, Fitriari Izzatunnisa Muhaimin, and Ahmad Fudhaili. "Tapak Liman (Elephantopus scaber) crude extract induces polyploidy in shallot root (Allium cepa war ascalonium (L))." E3S Web of Conferences 513 (2024): 03011. http://dx.doi.org/10.1051/e3sconf/202451303011.
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This study investigates the impact of induction time and concentration of Tapak Liman (Elephantopus scaber) crude extract on the effectiveness of polyploidy in shallot root (Allium cepa var ascalonium (L). Several parameters were observed, including the mitotic index of cells, the type of polyploidy, percentages of polyploidy cells, and the morphological changes in the polyploid shallot root (Allium cepa var ascalonium (L)) cell. Variations in the concentration of Elephantopus scaber extract were used namely 0% (control), 10%, 20%, and 30% in 100 ml of distilled water. The response variable was the percentages mitotic index formed. Control variables were the type of onion, the size of the onion, the extracted E. scaber variety, the extract volume, and the environmental conditions of the experiment. All parts of Tapak Liman as extracted using the water crude extraction method on all aspects of Tapak Liman. Red onion cell root preparations were squashed and dyed using hematoxylin dyes. The data obtained were mitotic index, % of polyploidy cell counts, polyploidy types, and morphological changes in the polyploid cell onion roots. Data are presented in tabular and graphical form and interpreted using quantitative descriptive and qualitative descriptive methods. From the research results, the best concentration to induce polyploidy in shallot root was 30% of Tapak Liman extract with a polyploid cell percentage of 58.65%. The best polyploid was 45 hours, with the percentage of polyploid-induced cells being 37.1%. The best combination of concentration and length of induction of crude extract of Tapak Liman was a concentration of 30% 45 hours induction time resulting in 87,35% polyploid cells.
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Thriveni, Vangapandu, Mouli Paul, Chakri Voruganti, Vadada Vinay Kumar, Jammugani Vinod Kumar, B. Sai Krishna Reddy, and Manoj Kumar. "Impact of Polyploidy on Crop Improvement and Plant Breeding Strategies: A Review." Journal of Advances in Biology & Biotechnology 27, no. 11 (November 13, 2024): 714–25. http://dx.doi.org/10.9734/jabb/2024/v27i111655.
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Polyploidy, the condition of possessing multiple sets of chromosomes, is a widespread phenomenon in plants that has had a profound impact on crop evolution and improvement. This review explores the role of polyploidy in plant breeding strategies, emphasizing its contributions to enhancing agronomic traits, overcoming genetic barriers, and expanding genetic diversity. Polyploid crops, such as wheat, cotton, and Brassica species, exhibit superior yield, increased biomass, and enhanced stress tolerance compared to their diploid counterparts. Polyploidy can arise naturally or be induced artificially, providing breeders with opportunities to create novel crop varieties through synthetic polyploidization. The complexity of polyploid genomes poses significant challenges, including fertility issues, meiotic instability, and difficulties in genome management. Advances in genomic and biotechnological tools, such as genomic selection and CRISPR-based genome editing, are beginning to address these obstacles, allowing for precise manipulation of polyploid genomes and improved breeding outcomes. Additionally, polyploidy plays a crucial role in overcoming reproductive barriers in interspecific hybrids, facilitating the transfer of desirable traits between species that would otherwise be genetically incompatible. The potential of polyploidy for developing climate-resilient crops is particularly noteworthy, as polyploid plants often exhibit greater tolerance to drought, salinity, and extreme temperatures. This makes polyploid breeding a promising approach for addressing the challenges of climate change and ensuring food security. Future research should focus on understanding the genetic and epigenetic mechanisms underlying polyploid genome stability and trait expression, as well as integrating advanced computational tools to predict and manipulate polyploid gene function. Emerging areas such as synthetic biology and multi-omics integration will further enhance our ability to engineer polyploid crops with complex trait architectures. Polyploidy remains a powerful and versatile tool for plant breeders, offering immense potential for crop improvement, genetic innovation, and the development of resilient agricultural systems. As the understanding and technological capabilities in polyploid breeding continue to advance, polyploid crops will play a central role in sustainable agricultural development and global food production.
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Zhao, Cunfeng, and Xianchun Zhang. "The Role of Polyploidy in the Genetic Structure and Expansion of Lepisorus clathratus in the Qinghai–Tibetan Plateau and Hengduan Mountains." Plants 13, no. 22 (November 13, 2024): 3181. http://dx.doi.org/10.3390/plants13223181.
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Polyploidy plays a crucial role in plant evolution, particularly in shaping genetic diversity and geographic distribution. This study investigates the genetic diversity and distribution of Lepisorus clathratus (C. B. Clarke) Ching, a polyploid fern species endemic to the Qinghai–Tibetan Plateau and Hengduan Mountains. We sampled 586 individuals from 66 populations and identified three ploidy levels: diploid, tetraploid, and hexaploid. Flow cytometry and chloroplast DNA sequencing were used to assess ploidy variation and genetic structure. Tetraploid populations dominated the Hengduan Mountains and exhibited wider geographic ranges, while diploids were largely confined to the Qinghai–Tibetan Plateau. Molecular variance analysis revealed significant genetic differentiation among regions, with polyploid populations demonstrating higher cross-region migration rates compared with diploids, as evidenced by the historical gene flow analysis. Ecological niche modeling suggested that polyploids expanded more successfully in post-glacial periods, likely due to their greater ecological flexibility and capacity for long-distance colonization. These findings highlight the critical role of polyploidy in shaping genetic structure and species expansion, contributing to the understanding of plant adaptation in response to historical climatic changes.
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Banerjee, Sonali, Sanjeet Singh Sandal, and Puneet Walia. "Advancing Soybean Resilience: The Role of Induced Polyploidy to Abiotic Stress Tolerance." Journal of Advances in Biology & Biotechnology 27, no. 7 (June 2, 2024): 1–9. http://dx.doi.org/10.9734/jabb/2024/v27i7961.
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Abiotic stress is one of the major constraints affecting the productivity of soybeans. It reduces germination ability, seedling growth, and development of the reproductive parts. Physiological traits, such as membrane and enzyme structure and functionality, are also negatively impacted due to the increased levels of reactive oxygen species (ROS). Polyploidy is known for creating diversification among plants, playing a key role in enhancing tolerance capacity against abiotic stress. These variations help plants survive under harsh conditions by modifying several morpho-physiological, molecular, and biochemical traits. However, polyploidy's role in enhancing tolerance to abiotic stress has been less explored in leguminous crops, particularly in soybeans. Additionally, no proper in-vitro or in-vivo techniques have been successfully employed to induce polyploidy in soybean and other legumes. Soybean, also known as soja bean or soya bean, has a history of polyploidy, which might be related to its tolerance mechanisms. This review paper discusses the limitations impacting soybean productivity under extreme environmental conditions and the role of synthetically developed polyploids in mitigating these abiotic stresses.
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Ramsey, Justin, and Tara S. Ramsey. "Ecological studies of polyploidy in the 100 years following its discovery." Philosophical Transactions of the Royal Society B: Biological Sciences 369, no. 1648 (August 5, 2014): 20130352. http://dx.doi.org/10.1098/rstb.2013.0352.
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Polyploidy is a mutation with profound phenotypic consequences and thus hypothesized to have transformative effects in plant ecology. This is most often considered in the context of geographical and environmental distributions—as achieved from divergence of physiological and life-history traits—but may also include species interactions and biological invasion. This paper presents a historical overview of hypotheses and empirical data regarding the ecology of polyploids. Early researchers of polyploidy (1910s–1930s) were geneticists by training but nonetheless savvy to its phenotypic effects, and speculated on the importance of genome duplication to adaptation and crop improvement. Cytogenetic studies in the 1930s–1950s indicated that polyploids are larger (sturdier foliage, thicker stems and taller stature) than diploids while cytogeographic surveys suggested that polyploids and diploids have allopatric or parapatric distributions. Although autopolyploidy was initially regarded as common, influential writings by North American botanists in the 1940s and 1950s argued for the principle role of allopolyploidy; according to this view, genome duplication was significant for providing a broader canvas for hybridization rather than for its phenotypic effects per se . The emphasis on allopolyploidy had a chilling effect on nascent ecological work, in part due to taxonomic challenges posed by interspecific hybridization. Nonetheless, biosystematic efforts over the next few decades (1950s–1970s) laid the foundation for ecological research by documenting cytotype distributions and identifying phenotypic correlates of polyploidy. Rigorous investigation of polyploid ecology was achieved in the 1980s and 1990s by population biologists who leveraged flow cytometry for comparative work in autopolyploid complexes. These efforts revealed multi-faceted ecological and phenotypic differences, some of which may be direct consequences of genome duplication. Several classical hypotheses about the ecology of polyploids remain untested, however, and allopolyploidy—regarded by most botanists as the primary mode of genome duplication—is largely unstudied in an ecological context.
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Schmid, Michael, Ben J. Evans, and James P. Bogart. "Polyploidy in Amphibia." Cytogenetic and Genome Research 145, no. 3-4 (2015): 315–30. http://dx.doi.org/10.1159/000431388.
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This review summarizes the current status of the known extant genuine polyploid anuran and urodelan species, as well as spontaneously originated and/or experimentally produced amphibian polyploids. The mechanisms by which polyploids can originate, the meiotic pairing configurations, the diploidization processes operating in polyploid genomes, the phenomenon of hybridogenesis, and the relationship between polyploidization and sex chromosome evolution are discussed. The polyploid systems in some important amphibian taxa are described in more detail.
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Adams, Keith L. "Insights into the evolution of duplicate gene expression in polyploids from GossypiumThis paper is one of a selection of papers published in the Special Issue on Systematics Research." Botany 86, no. 8 (August 2008): 827–34. http://dx.doi.org/10.1139/b08-042.
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Polyploidy is a prominent mechanism of speciation in plants that can lead to novel phenotypes. Polyploidy is characterized by novel genetic and genomic consequences that provide raw material for morphological evolution. Polyploids often exhibit changes in genome organization and gene expression compared with their diploid progenitors. The five allopolyploid cotton (Gossypium) species and newly created cotton neopolyploids have been developed as a useful group for studies of duplicated gene expression in polyploids. Here I review recent studies on the evolution of duplicate gene expression in polyploid cotton. In addition I present new expression data from cotton neopolyploids that address the effects on expression of adding a third genome in an allohexaploid, and that provide insights into fine scale organ-specific silencing. Substantial changes in gene expression have occurred in homoeologous genes (gene pairs duplicated by polyploidy), including organ-specific gene silencing and subfunctionalization. Many of the changes in gene expression have occurred on an evolutionary timescale, whereas others occur immediately after genome merger and within a few generations. Abiotic stress can affect the expression of homoeologous gene expression, causing expression partitioning between homoeologs. To examine the effects of interspecific hybridization, without chromosome doubling, on gene expression, interspecific hybrids have been studied. Extensive variation in allelic expression was observed upon hybridization that varied by gene, organ, and genotype. Several hypotheses have been proposed for why gene expression is altered in allopolyploids and interspecific hybrids.
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Trojak-Goluch, Anna, Magdalena Kawka-Lipińska, Katarzyna Wielgusz, and Marcin Praczyk. "Polyploidy in Industrial Crops: Applications and Perspectives in Plant Breeding." Agronomy 11, no. 12 (December 17, 2021): 2574. http://dx.doi.org/10.3390/agronomy11122574.
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Polyploidisation is an important process in the evolution of many plant species. An additional set of chromosomes can be derived from intraspecific genome duplication (autopolyploidy) or hybridising divergent genomes and chromosome doubling (allopolyploidy). Special forms of polyploidy are autoallopolyploidy and segmental allopolyploidy. Polyploidy arises from two basic processes: spontaneously occurring disturbances of meiotic division and induced by antimitotic agents’ disruption of mitosis. The first involves the induction and fusion of unreduced gametes, resulting in the formation of triploids and tetraploids. The second process uses antimitotics that disrupt cellular microtubules and prevent chromosome’s sister chromatids motion during anaphase. Colchicine, oryzalin, and trifluralin are the most commonly used antimitotics for inducing polyploids in plants. The exposure time and concentration of the antimitotics and the species, cultivar, genotype, and tissue type affect the efficiency of genome duplication. Polyploids are distinguished from diploids by increased cell size and vegetative parts of plants and increased content of secondary metabolites. Genome duplication generates several changes at the epigenetic level resulting in altered gene expression. Polyploidisation is used in plant breeding to overcome the non-viability and infertility of interspecific hybrids, obtain seedless polyploid cultivars and increase resistance/tolerance to biotic and abiotic factors.
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Mangena, Phetole. "Impact of Polyploidy Induction for Salinity Stress Mitigation in Soybean (Glycine max L. Merrill)." Plants 12, no. 6 (March 17, 2023): 1356. http://dx.doi.org/10.3390/plants12061356.
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Polyploidy induction is recognized as one of the major evolutionary processes leading to remarkable morphological, physiological, and genetic variations in plants. Soybean (Glycine max L.), also known as soja bean or soya bean, is an annual leguminous crop of the pea family (Fabaceae) that shares a paleopolypoidy history, dating back to approximately 56.5 million years ago with other leguminous crops such as cowpea and other Glycine specific polyploids. This crop has been documented as one of the polyploid complex species among legumes whose gene evolution and resultant adaptive growth characteristics following induced polyploidization has not been fully explored. Furthermore, no successfully established in vivo or in vitro based polyploidy induction protocols have been reported to date, particularly, with the intention to develop mutant plants showing strong resistance to abiotic salinity stress. This review, therefore, describes the role of synthetic polyploid plant production in soybean for the mitigation of high soil salt stress levels and how this evolving approach could be used to further enhance the nutritional, pharmaceutical and economic industrial value of soybeans. This review also addresses the challenges involved during the polyploidization process.
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Donne, Romain, Flora Sangouard, Séverine Celton-Morizur, and Chantal Desdouets. "Hepatocyte Polyploidy: Driver or Gatekeeper of Chronic Liver Diseases." Cancers 13, no. 20 (October 14, 2021): 5151. http://dx.doi.org/10.3390/cancers13205151.
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Polyploidy, also known as whole-genome amplification, is a condition in which the organism has more than two basic sets of chromosomes. Polyploidy frequently arises during tissue development and repair, and in age-associated diseases, such as cancer. Its consequences are diverse and clearly different between systems. The liver is a particularly fascinating organ in that it can adapt its ploidy to the physiological and pathological context. Polyploid hepatocytes are characterized in terms of the number of nuclei per cell (cellular ploidy; mononucleate/binucleate hepatocytes) and the number of chromosome sets in each nucleus (nuclear ploidy; diploid, tetraploid, octoploid). The advantages and disadvantages of polyploidy in mammals are not fully understood. About 30% of the hepatocytes in the human liver are polyploid. In this review, we explore the mechanisms underlying the development of polyploid cells, our current understanding of the regulation of polyploidization during development and pathophysiology and its consequences for liver function. We will also provide data shedding light on the ways in which polyploid hepatocytes cope with centrosome amplification. Finally, we discuss recent discoveries highlighting the possible roles of liver polyploidy in protecting against tumor formation, or, conversely, contributing to liver tumorigenesis.
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Manzoor, Ayesha, Touqeer Ahmad, Muhammad Ajmal Bashir, Mirza Muhammad Qadeer Baig, Abdul Ahad Quresh, Muhammad Kausar Nawaz Shah, and Ishfaq Ahmed Hafiz. "Induction and identification of colchicine induced polyploidy in Gladiolus grandiflorus ‘White Prosperity’." Folia Horticulturae 30, no. 2 (December 1, 2018): 307–19. http://dx.doi.org/10.2478/fhort-2018-0026.
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Abstract Gladiolus is one of the most important lucrative cut flower crops that is commercially cultivated worldwide due to its various spike forms, size, and shape and color combinations. In order to further increase the commercial and horticultural value by improving the ornamental traits of gladiolus ‘White Prosperity’, polyploidy was induced by soaking gladiolus corms in different colchicine concentrations (0.1%, 0.2% and 0.3%) for 24 h. Different colchicine concentrations had a little effect on sprouting and survival percentage but it significantly delayed the emergence of sprouts. About one third decreases in plant height along with reduction in number of leaves per plant, leaf area, length and width, chlorophyll content, diameter and number of cormlets per corm was observed in treated plants. Colchicine at 0.1% concentration improved the ornamental value of gladiolus by increasing vase life whereas colchicine at 0.3% was effective in increasing floret diameter. However, the colchicine treated plants exhibited delayed and reduced percentage of flowering corms. Pollen and stomatal study was done for the identification of polyploidy and it showed that both pollen and stomata size were increased while stomatal density and pollen fertility was significantly reduced in polyploid plants. Induction of polyploidy (mixoploids + octoploids) was achieved in all concentrations, however 0.2% and 0.3% concentrations of colchicine were effective for producing large number of polyploid plants. But at 0.1% concentration of colchicine, majority of plants did not show any change in their original ploidy level (tetraploid). These putative polyploids may be helpful for further improvement in ornamental and horticultural value of gladiolus.
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Li, Xinxin, and Baocheng Guo. "Substantially adaptive potential in polyploid cyprinid fishes: evidence from biogeographic, phylogenetic and genomic studies." Proceedings of the Royal Society B: Biological Sciences 287, no. 1920 (February 12, 2020): 20193008. http://dx.doi.org/10.1098/rspb.2019.3008.
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Whole genome duplication (WGD) is commonly believed to play key roles in vertebrate evolution. However, nowadays polyploidy exists in a few fish, amphibian and reptile groups only, and seems to be an evolutionary dead end in vertebrates. We investigate the evolutionary significance of polyploidization in Cyprinidae—a fish family that contains more polyploid species than any other vertebrate group—with integrated biogeographic, phylogenetic and genomic analyses. First, polyploid species are found to be significantly frequent in areas of higher altitude and lower mean annual temperature compared with diploid species in Cyprinidae. Second, a polyploidy-related diversification rate shift is observed in Cyprinidae. This increased net diversification rate is only seen in three polyploid lineages, and other polyploid lineages have similar net diversification rate as well as diploid lineages in Cyprinidae. Interestingly, significant ‘lag times’ existed between polyploidization and radiation in Cyprinidae. Multiple polyploid lineages were established approximately 15 Ma through recurrent allopolyploidization events, but the net diversification rate did not start to increase until approximately 5 Ma—long after polyploidization events. Environmental changes associated with the continuous uplift of the Tibetan Plateau and climate change have probably promoted the initial establishment and subsequent radiation of polyploidy in Cyprinidae. Finally, the unique retention of duplicated genes in polyploid cyprinids adapted to harsh environments is found. Taken together, our results suggest that polyploidy in Cyprinidae is far more than an evolutionary dead end, but rather shows substantially adaptive potential. Polyploid cyprinids thus constitute an ideal model system for unveiling largely unexplored consequences of WGD in vertebrates, from genomic evolution to species diversification.
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Román-Palacios, Cristian, Y. Franchesco Molina-Henao, and Michael S. Barker. "Polyploids increase overall diversity despite higher turnover than diploids in the Brassicaceae." Proceedings of the Royal Society B: Biological Sciences 287, no. 1934 (September 2, 2020): 20200962. http://dx.doi.org/10.1098/rspb.2020.0962.
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Although polyploidy is widespread across the plant Tree of Life, its long-term evolutionary significance is still poorly understood. Here, we examine the effects of polyploidy in explaining the large-scale evolutionary patterns within angiosperms by focusing on a single family exhibiting extensive interspecific variation in chromosome numbers. We inferred ploidy from haploid chromosome numbers for 80% of species in the most comprehensive species-level chronogram for the Brassicaceae. After evaluating a total of 94 phylogenetic models of diversification, we found that ploidy influences diversification rates across the Brassicaceae. We also found that despite diversifying at a similar rate to diploids, polyploids have played a significant role in driving present-day differences in species richness among clades. Overall, in addition to highlighting the complexity in the evolutionary consequences of polyploidy, our results suggest that rare successful polyploids persist while significantly contributing to the long-term evolution of clades. Our findings further indicate that polyploidy has played a major role in driving the long-term evolution of the Brassicaceae and highlight the potential of polyploidy in shaping present-day diversity patterns across the plant Tree of Life.
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Suda, Jan, and Tomáš Herben. "Ploidy frequencies in plants with ploidy heterogeneity: fitting a general gametic model to empirical population data." Proceedings of the Royal Society B: Biological Sciences 280, no. 1751 (January 22, 2013): 20122387. http://dx.doi.org/10.1098/rspb.2012.2387.
Full textAbstract:
Genome duplication (polyploidy) is a recurrent evolutionary process in plants, often conferring instant reproductive isolation and thus potentially leading to speciation. Outcome of the process is often seen in the field as different cytotypes co-occur in many plant populations. Failure of meiotic reduction during gametogenesis is widely acknowledged to be the main mode of polyploid formation. To get insight into its role in the dynamics of polyploidy generation under natural conditions, and coexistence of several ploidy levels, we developed a general gametic model for diploid–polyploid systems. This model predicts equilibrium ploidy frequencies as functions of several parameters, namely the unreduced gamete proportions and fertilities of higher ploidy plants. We used data on field ploidy frequencies for 39 presumably autopolyploid plant species/populations to infer numerical values of the model parameters (either analytically or using an optimization procedure). With the exception of a few species, the model fit was very high. The estimated proportions of unreduced gametes (median of 0.0089) matched published estimates well. Our results imply that conditions for cytotype coexistence in natural populations are likely to be less restrictive than previously assumed. In addition, rather simple models show sufficiently rich behaviour to explain the prevalence of polyploids among flowering plants.
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Silvestrini, Milene, Cecília A. F. Pinto-Maglio, Maria I. Zucchi, and Flavio A. M. dos Santos. "Cytogenetics and characterization of microsatellite loci for a South American pioneer tree species, Croton floribundus." Genome 56, no. 12 (December 2013): 743–51. http://dx.doi.org/10.1139/gen-2013-0159.
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Despite the recent advances in plant population genetic studies, the lack of information regarding pedigree, ploidy level, or mode of inheritance for many polyploids can compromise the analysis of the molecular data produced. The aim of this study was to examine both microsatellite and cytogenetic characteristics of the pioneer tree Croton floribundus Spreng. (Euphorbiaceae) to test for the occurrence of polyploidy in the species and to evaluate its implications for the appropriate use of SSR markers. Seven microsatellite markers were developed and screened for 62 individuals from a semi-deciduous tropical forest in Brazil. Chromosome number, meiotic behavior, and pollen viability were evaluated from male flower buds. All SSR loci were highly polymorphic. The number of bivalents observed in meiosis n = 56 (2n = 8× = 112) and the maximum number of alleles per individual (Ni = 8) demonstrated the occurrence of polyploidy in C. floribundus. The normal meiotic pairing and the high pollen viability suggested that C. floribundus is a regular and stable polyploid, most likely an allopolyploid. The combined SSR and cytogenetic data provided new evidence on the origin and evolution of the species as well as assured the accurate use of SSR loci for population genetic studies of the polyploid pioneer species.
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Leung, Kelley, Louis van de Zande, and Leo W. Beukeboom. "Effects of polyploidization and their evolutionary implications are revealed by heritable polyploidy in the haplodiploid wasp Nasonia vitripennis." PLOS ONE 18, no. 11 (November 2, 2023): e0288278. http://dx.doi.org/10.1371/journal.pone.0288278.
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Recurrent polyploidization occurred in the evolutionary history of most Eukaryota. However, how neopolyploid detriment (sterility, gigantism, gene dosage imbalances) has been overcome and even been bridged to evolutionary advantage (gene network diversification, mass radiation, range expansion) is largely unknown, particularly for animals. We used the parasitoid wasp Nasonia vitripennis, a rare insect system with heritable polyploidy, to begin addressing this knowledge gap. In Hymenoptera the sexes have different ploidies (haploid males, diploid females) and neopolyploids (diploid males, triploid females) occur for various species. Although such polyploids are usually sterile, those of N. vitripennis are reproductively capable and can even establish stable polyploid lines. To assess the effects of polyploidization, we compared a long-established polyploid line, the Whiting polyploid line (WPL) and a newly generated transformer knockdown line (tKDL) for fitness traits, absolute gene expression, and cell size and number. WPL polyploids have high male fitness and low female fecundity, while tKDL polyploids have poor male mate competition ability and high fertility. WPL has larger cells and cell number reduction, but the tKDL does not differ in this respect. Expression analyses of two housekeeping genes indicated that gene dosage is linked to sex irrespective of ploidy. Our study suggests that polyploid phenotypic variation may explain why some polyploid lineages thrive and others die out; a commonly proposed but difficult-to-test hypothesis. This documentation of diploid males (tKDL) with impaired competitive mating ability; triploid females with high fitness variation; and hymenopteran sexual dosage compensation (despite the lack of sex chromosomes) all challenges general assumptions on hymenopteran biology. We conclude that polyploidization is dependent on the duplicated genome characteristics and that genomes of different lines are unequally suited to survive diploidization. These results demonstrate the utility of N. vitripennis for delineating mechanisms of animal polyploid evolution, analogous to more advanced polyploid plant models.
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Ribeiro da Costa, Itayguara, and Eliana Regina Forni-Martins. "Chromosome studies in species of Eugenia, Myrciaria and Plinia (Myrtaceae) from south-eastern Brazil." Australian Journal of Botany 54, no. 4 (2006): 409. http://dx.doi.org/10.1071/bt04199.
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The chromosome numbers of Brazilian species of Myrtaceae were reassessed in the context of chromosomal evolution in fleshy-fruited Myrteae. The chromosome numbers of 14 species of Eugenia, three of Myrciaria and two of Plinia were determined, 14 of which had not been published before. In Eugenia, a diploid state (2n = 22) was found in nine species, polyploid (2n = 33 or 2n = 44) in three species, and both diploid and polyploid cytotypes in another three species. The percentage of Eugenia species with a known chromosome number increased from 19 to 31 species, 22.6% of which were polyploid (3 triploid, 1 tetraploid and 3 hexaploid) and a further 16.1% either dysploid from the triploid level or had both diploid and polyploid races, giving a total of 38.7% in which polyploidy is recorded. In Myrciaria (3 species) and Plinia (2 species), the chromosome number was 2n = 22, with no polyploidy known in these genera. The results reinforce the previous indications that polyploidy is of great importance in the evolution of fleshy-fruited Myrteae.
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Hd Putri, Rani Dwi Suci, Zuhratul Mardhiyah Amir, Lufri Lufri, Yuni Ahda, and Abdul Razak. "Kajian Variasi Poliploidi pada Ikan Lele Afrika (Clarias gariepinus)." BIOEDUSAINS:Jurnal Pendidikan Biologi dan Sains 4, no. 2 (September 6, 2021): 239–45. http://dx.doi.org/10.31539/bioedusains.v4i2.1892.
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This study aims to explain the variation of polyploidy in catfish. This research method is literature study and literature review. The results showed that there were several forms of polyploid interpretation that were often performed on Clarias gariepinus. The effects of fish polyploidy will produce fish seeds with several advantages such as fast growth, resistance to disease and high tolerance to the environment. In conclusion, the form of variation that is often done produces tetraploid and triploid catfish.
Keywords: Polyploidy, Tetraploid, Triploid
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Ahuja, M. Raj. "Polyploidy in Gymnosperms: Revisited." Silvae Genetica 54, no. 1-6 (December 1, 2005): 59–69. http://dx.doi.org/10.1515/sg-2005-0010.
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Abstract There are only a few natural polyploids in gymnosperms. These have been reported in Ephera spp. (Gnetales), and Juniperus chinensis ‘Pfitzeriana’ (2n = 4x = 44), Fitzroya cupressoides (2n = 4x = 44), and the only hexaploid conifer Sequoia sempervirens (2n = 6x = 66) (Coniferales). Sporadic polyploids and aneuploids occur at a very low frequency in nurseries in conifers, but most of them show growth abnormalities, remain dwarf, and may not reach maturity. One exception is an autotetraploid tree of Larix decidua (2n = 4x = 48) that has survived in a private estate in Denmark. Colchicine-induced polyploids (colchiploids) have been produced in a several genera of conifers, including, Pinus, Picea, and Larix. These colchiploids (Co) were hybridized to untreated diploids to produce C1 and C2 generations to investigate their chromosome behavior. The colchiploids showed a wide range of chromosome variability, ranging from diploids, triploids, and tetraploids, and many were mixoploids. The colchiploids also show growth retardation, remain dwarf, and their future potential applications in forestry remains uncertain. However, genetic variability in the colchiploids still offers prospects for isolating genetically stable new genotypes. Even though polyploidy is rare in extant conifers, is it possible that ancient polyploidy or paleopolyploidy, that is prevalent in angiosperms, has also played a role in the evolution of conifers. In this paper we shall review the current status of polyploidy in gymnosperms.
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Garcia, Sònia, Teresa Garnatje, Jaume Pellicer, E. Durant McArthur, Sonja Siljak-Yakovlev, and Joan Vallès. "Ribosomal DNA, heterochromatin, and correlation with genome size in diploid and polyploid North American endemic sagebrushes (Artemisia, Asteraceae)." Genome 52, no. 12 (December 2009): 1012–24. http://dx.doi.org/10.1139/g09-077.
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Subgenus Tridentatae ( Artemisia , Asteraceae) can be considered a polyploid complex. Both polyploidy and hybridization have been documented in the Tridentatae. Fluorescent in situ hybridization (FISH) and fluorochrome banding were used to detect and analyze ribosomal DNA changes linked to polyploidization in this group by studying four diploid-polyploid species pairs. In addition, genome sizes and heterochromatin patterns were compared between these populations. The linked 5S and 35S rRNA genes are confirmed as characteristic for Artemisia, and a pattern at the diploid level of three rDNA loci located at telomeric positions proved to be typical. Loss of rDNA loci was observed in some polyploids, whereas others showed additivity with respect to their diploid relatives. Genome downsizing was observed in all polyploids. Banding patterns differed depending on the pair of species analysed, but some polyploid populations showed an increased number of heterochromatic bands. FISH and fluorochrome banding were useful in determining the systematic position of Artemisia bigelovii , for which a differential pattern was found as compared with the rest of the group. Additionally, FISH was used to detect the presence of the Arabidopsis-type telomere repeat for the first time in Artemisia.
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Schoenfelder, Kevin P., and Donald T. Fox. "The expanding implications of polyploidy." Journal of Cell Biology 209, no. 4 (May 25, 2015): 485–91. http://dx.doi.org/10.1083/jcb.201502016.
Full textAbstract:
Polyploid cells, which contain more than two genome copies, occur throughout nature. Beyond well-established roles in increasing cell size/metabolic output, polyploidy can also promote nonuniform genome, transcriptome, and metabolome alterations. Polyploidy also frequently confers resistance to environmental stresses not tolerated by diploid cells. Recent progress has begun to unravel how this fascinating phenomenon contributes to normal physiology and disease.
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Wang, Longfei, Shuai Cao, Peitong Wang, Kening Lu, Qingxin Song, Fang-Jie Zhao, and Z. Jeffrey Chen. "DNA hypomethylation in tetraploid rice potentiates stress-responsive gene expression for salt tolerance." Proceedings of the National Academy of Sciences 118, no. 13 (March 26, 2021): e2023981118. http://dx.doi.org/10.1073/pnas.2023981118.
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Polyploidy is a prominent feature for genome evolution in many animals and all flowering plants. Plant polyploids often show enhanced fitness in diverse and extreme environments, but the molecular basis for this remains elusive. Soil salinity presents challenges for many plants including agricultural crops. Here we report that salt tolerance is enhanced in tetraploid rice through lower sodium uptake and correlates with epigenetic regulation of jasmonic acid (JA)–related genes. Polyploidy induces DNA hypomethylation and potentiates genomic loci coexistent with many stress-responsive genes, which are generally associated with proximal transposable elements (TEs). Under salt stress, the stress-responsive genes including those in the JA pathway are more rapidly induced and expressed at higher levels in tetraploid than in diploid rice, which is concurrent with increased jasmonoyl isoleucine (JA-Ile) content and JA signaling to confer stress tolerance. After stress, elevated expression of stress-responsive genes in tetraploid rice can induce hypermethylation and suppression of the TEs adjacent to stress-responsive genes. These induced responses are reproducible in a recurring round of salt stress and shared between two japonica tetraploid rice lines. The data collectively suggest a feedback relationship between polyploidy-induced hypomethylation in rapid and strong stress response and stress-induced hypermethylation to repress proximal TEs and/or TE-associated stress-responsive genes. This feedback regulation may provide a molecular basis for selection to enhance adaptation of polyploid plants and crops during evolution and domestication.
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Manzoor, Ayesha, Touqeer Ahmad, Muhammad Bashir, Ishfaq Hafiz, and Cristian Silvestri. "Studies on Colchicine Induced Chromosome Doubling for Enhancement of Quality Traits in Ornamental Plants." Plants 8, no. 7 (June 28, 2019): 194. http://dx.doi.org/10.3390/plants8070194.
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Polyploidy has the utmost importance in horticulture for the development of new ornamental varieties with desirable morphological traits referring to plant size and vigor, leaf thickness, larger flowers with thicker petals, intense color of leaves and flowers, long lasting flowers, compactness, dwarfness and restored fertility. Polyploidy may occur naturally due to the formation of unreduced gametes or can be artificially induced by doubling the number of chromosomes in somatic cells. Usually, natural polyploid plants are unavailable, so polyploidy is induced synthetically with the help of mitotic inhibitors. Colchicine is a widely used mitotic inhibitor for the induction of polyploidy in plants during their cell division by inhibiting the chromosome segregation. Different plant organs like seeds, apical meristems, flower buds, and roots can be used to induce polyploidy through many application methods such as dipping/soaking, dropping or cotton wool. Flow cytometry and chromosome counting, with an observation of morphological and physiological traits are routine procedures for the determination of ploidy level in plants.
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Bou-Nader, Myriam, Stefano Caruso, Romain Donne, Séverine Celton-Morizur, Julien Calderaro, Géraldine Gentric, Mathilde Cadoux, et al. "Polyploidy spectrum: a new marker in HCC classification." Gut 69, no. 2 (April 12, 2019): 355–64. http://dx.doi.org/10.1136/gutjnl-2018-318021.
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ObjectivesPolyploidy is a fascinating characteristic of liver parenchyma. Hepatocyte polyploidy depends on the DNA content of each nucleus (nuclear ploidy) and the number of nuclei per cell (cellular ploidy). Which role can be assigned to polyploidy during human hepatocellular carcinoma (HCC) development is still an open question. Here, we investigated whether a specific ploidy spectrum is associated with clinical and molecular features of HCC.DesignPloidy spectra were determined on surgically resected tissues from patients with HCC as well as healthy control tissues. To define ploidy profiles, a quantitative and qualitative in situ imaging approach was used on paraffin tissue liver sections.ResultsWe first demonstrated that polyploid hepatocytes are the major components of human liver parenchyma, polyploidy being mainly cellular (binuclear hepatocytes). Across liver lobules, polyploid hepatocytes do not exhibit a specific zonation pattern. During liver tumorigenesis, cellular ploidy is drastically reduced; binuclear polyploid hepatocytes are barely present in HCC tumours. Remarkably, nuclear ploidy is specifically amplified in HCC tumours. In fact, nuclear ploidy is amplified in HCCs harbouring a low degree of differentiation and TP53 mutations. Finally, our results demonstrated that highly polyploid tumours are associated with a poor prognosis.ConclusionsOur results underline the importance of quantification of cellular and nuclear ploidy spectra during HCC tumorigenesis.
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Masterson, Jane. "The geological history of polyploidy in woody angiosperms." Paleontological Society Special Publications 6 (1992): 203. http://dx.doi.org/10.1017/s2475262200007632.
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Polyploidy, the condition where an organism has more than two complete sets of chromosomes, is a common and important evolutionary phenomenon in flowering plants (angiosperms). Estimates of the percentage of angiosperms (approximately 250-300,000 living species) derived from polyploids range from 47-90%. The historical development of polyploidy is currently very poorly understood and whether polyploidy is a major causal factor in angiosperm diversification is widely debated.Many questions about the base chromosome number of angiosperms (important for establishing the extent of polyploidy) and the origin of polyploidy can be addressed using fossil plants. One of the physical effects of polyploidy is a general increase in cell volume; the size of guard cells (leaf epidermal cells that control the opening and closing of the gas exchange pores [stomata]) has been used successfully to determine the relative number of chromosomes present or ploidy level in living Carva (hickories), Betula (birch), Magnolia, and Pvrus (pear). At least two previous studies have used guard cells to estimate ploidy level in fossil taxa (Metasequoia, Sequoia, and Paleorubiaceophyllum).The base haploid chromosome number in angiosperms generally has been assumed to be between n=7-9, but this is apparently based either on the dubious assumption that the most common condition is likely to be primitive (cf. egg laying in mammals) or the inference that because this number is found in many different clades it is likely to be basic in each of these groups. The Gnetales (the living gymnosperms most closely related to angiosperms) have a haploid basic number of 7, but Donoghue and Doyle (1989) find that it is almost equally parsimonious to assume the base number is n=12-14 because of uncertainties over the chromosome number of certain critical extinct outgroups. My guard cell measurements of three angiosperm families (Platanaceae, Magnoliaceae and Lauraceae) provide additional empirical support for the n=7-9 hypothesis and suggest that extinct diploid members existed in the mid-Cretaceous and early Cenozoic floras. These results also falsify the hypothesis that polyploidization triggered the angiosperm radiation in the Cretaceous in these families. Other hypotheses regarding the historical timing of major increases in polyploidy are being tested. These include climatic deterioration and associated modification and mixing of plant distributions during the Eocene and Pleistocene. It may be that polyploids survive major disturbances at a higher rate than diploids because they often have broader ecological tolerances and wider geographic ranges. Thus the accumulation of polyploids in plant families may not occur because they are speciation prone as usually inferred but because they are extinction resistant. My preliminary results in Platanaceae support an increased level of polyploidy after major disturbances.
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Kürschner, Wolfram M., Sietske J. Batenburg, and Luke Mander. "Aberrant Classopollis pollen reveals evidence for unreduced (2 n ) pollen in the conifer family Cheirolepidiaceae during the Triassic–Jurassic transition." Proceedings of the Royal Society B: Biological Sciences 280, no. 1768 (October 7, 2013): 20131708. http://dx.doi.org/10.1098/rspb.2013.1708.
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Polyploidy (or whole-genome doubling) is a key mechanism for plant speciation leading to new evolutionary lineages. Several lines of evidence show that most species among flowering plants had polyploidy ancestry, but it is virtually unknown for conifers. Here, we study variability in pollen tetrad morphology and the size of the conifer pollen type Classopollis extracted from sediments of the Triassic–Jurassic transition, 200 Ma. Classopollis producing Cheirolepidiaceae were one of the most dominant and diverse groups of conifers during the Mesozoic. We show that aberrant pollen Classopollis tetrads, triads and dyads, and the large variation in pollen size indicates the presence of unreduced (2 n ) pollen, which is one of the main mechanisms in modern polyploid formation. Polyploid speciation may explain the high variability of growth forms and adaptation of these conifers to different environments and their resistance to extreme growth conditions. We suggest that polyploidy may have also reduced the extinction risk of these conifers during the End-Triassic biotic crisis.
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Azmi, Tubagus Kiki Kawakibi, Dewi Sukma, Sandra Arifin Aziz, and Dan Muhamad Syukur. "Morfologi dan Pertumbuhan Planlet Hasil Induksi Poliploidi melalui Perlakuan Kolkisin pada Kuncup Bunga Anggrek Bulan (Phalaenopsis amabilis (L.) Blume)." Jurnal Agronomi Indonesia (Indonesian Journal of Agronomy) 44, no. 1 (June 24, 2016): 68. http://dx.doi.org/10.24831/jai.v44i1.12503.
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<br />Induction of polyploid gametes is one of useful plant polyploidization methods. Some of its benefits are to obtain triploid and tetraploid progenies at the same time by cross and self pollination. Previous research showed that some morphological characters which could be the indications of polyploidy plantlets before the analysis of chromosome number. Colchicine treatment on flower bud of diploid Phalaenopsis amabilis was conducted to determine the effect of colchicine on flower bud development, plantlets morphology and growth, and potential of polyploidy induction based on plantlets morphology. Colchicine concentrations in the experiment were 0, 50, 500, 1,000, and 2,000 mg L-1, with three days duration of treatments with aluminium foil wraps on flower buds. The results showed that high colchicine concentrations (2,000 mg L-1) inhibited flowers blooming of treated flower buds. Based on morphological characters, plantlets were classified into normal and putative polyploid plantlets. Putative polyploid plantlets from colchicine with the concentration of 50, 500, and 1,000 mg L-1 were 71.2, 86.4, and 100.0% respectively.<br /><br />Keywords: colchicine concentration, morphological characters, normal plantlets, putative polyploidy, reproductive organ<br /><br />
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Deans, Lauren E., Irene E. Palmer, Darren H. Touchell, and Thomas G. Ranney. "In Vitro Induction and Characterization of Polyploid Hydrangea macrophylla and H. serrata." HortScience 56, no. 6 (June 2021): 709–15. http://dx.doi.org/10.21273/hortsci15783-21.
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Hydrangea macrophylla (Thunb.) Ser. and H. serrata (Thunb.) Ser. are popular and commercially important landscape and floriculture crops. Although both species are typically diploid, induced polyploids often exhibit horticulturally valuable traits. Procedures for inducing polyploidy vary by species and often have low or inconsistent efficacy. In this study, oryzalin and nitrotyrosine were investigated as in vitro mitotic inhibitors for inducing polyploidy in H. macrophylla ‘Robert’ and H. serrata ‘MAK20’. First, shoot apices of ‘MAK20’ were treated with 15 μm oryzalin for 0, 2, 4, 6, or 8 days, and the ploidy of shoots was determined after 8 weeks. A regression analysis showed that the proportion of polyploids (tetraploid plus mixoploid shoots) increased with the exposure duration. During a follow-up experiment, ‘MAK20’ and ‘Robert’ were treated with oryzalin (0 or 15 μm) and nitrotyrosine (0, 25, 50, and 100 µm for ‘MAK20’ and 0, 12.5, 25, 50, and 100 µm for ‘Robert’) in a factorial treatment arrangement. Oryzalin, nitrotyrosine, and their interaction influenced polyploid frequency for ‘Robert’, whereby the combination of oryzalin (15 μm) and nitrotyrosine (50 μm) resulted in the highest polyploid induction of 50%. Oryzalin influenced polyploid frequency for ‘MAK20’ ( = 30.4%), but not nitrotyrosine or the interaction between nitrotyrosine and oryzalin. Morphology and pollen germination of these autotetraploid ‘Robert’, ‘MAK20’, and previously developed autotetraploid H. macrophylla ‘David Ramsey’ plants were compared with their diploid counterparts 1 year after plants were moved ex vitro. Compared with diploids, tetraploid hydrangeas had larger leaves, thicker stems, lower leaf area/fresh weight ratios, and longer internodes. Although all tetraploids exhibited fewer inflorescences per plant, both H. macrophylla cultivars had larger inflorescence diameters and ‘David Ramsey’ had a greater number of showy florets (sterile florets with enlarged, decorative sepals) per inflorescence. Sepal colors were compared using International Commission on Illumination L*a*b* color space. Tetraploid ‘MAK20’ had lower L* values (darker sepals), and tetraploid ‘Robert’ and ‘MAK20’ both had higher a* values (redder sepals). Pollen germination rates were greatly reduced in all tetraploid lines, but they retained some viability. These results provide an effective protocol for in vitro polyploid induction of Hydrangea sp. and documented certain desirable traits associated with tetraploid phenotypes.
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Wallace, Mark J., Siegfried L. Krauss, and Matthew D. Barrett. "Complex genetic relationships within and among cytotypes in the Lepidosperma costale species complex (Cyperaceae) on rocky outcrops in Western Australia." Australian Journal of Botany 67, no. 3 (2019): 205. http://dx.doi.org/10.1071/bt18103.
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There is a growing realisation that cytotype variation within species complexes plays an important role in plant evolution; however, there are relatively few investigations that describe the genetic diversity within and among related cytotypes. In the present study, we analysed patterns of genetic variation in 774 individuals from nine diploid, 14 tetraploid and five mixed ploidy populations of the Lepidosperma costale complex (Cyperaceae) from rocky outcrops in south-west Australia. Application of nuclear (nSSR) and chloroplast (cpSSR) microsatellites suggests that polyploids are of autopolyploid and allopolyploid origin and that polyploidisation is associated with a shift to facultative clonal reproduction, including apomictic reproduction. The newly-discovered putative allopolyploids were commonly associated with disturbed environments, an association commonly reported for allopolyploids. Diploid populations generally contained more genetic diversity than polyploid populations, and there was little genetic differentiation among diploid populations. In contrast, polyploids were characterised by higher heterozygosity and differentiation among populations, but possessed lower within-population diversity. The high differentiation among polyploid populations suggests that polyploids may have formed recurrently and are an important component of morphologically cryptic diversity within the species complex. Ploidy level is a critical factor affecting genetic diversity in this species complex, highlighting the potential contributions of polyploidy to genetic differentiation, and potentially speciation.
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Chumová, Zuzana, Terezie Mandáková, and Pavel Trávníček. "On the Origin of Tetraploid Vernal Grasses (Anthoxanthum) in Europe." Genes 12, no. 7 (June 24, 2021): 966. http://dx.doi.org/10.3390/genes12070966.
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Polyploidy has played a crucial role in the evolution of many plant taxa, namely in higher latitudinal zones. Surprisingly, after several decades of an intensive research on polyploids, there are still common polyploid species whose evolutionary history is virtually unknown. Here, we addressed the origin of sweet vernal grass (Anthoxanthum odoratum) using flow cytometry, DNA sequencing, and in situ hybridization-based cytogenetic techniques. An allotetraploid and polytopic origin of the species has been verified. The chromosome study reveals an extensive variation between the European populations. In contrast, an autopolyploid origin of the rarer tetraploid vernal grass species, A. alpinum, has been corroborated. Diploid A. alpinum played an essential role in the polyploidization of both European tetraploids studied.