#polyploidy
- Allopolyploid — An organism, cell, or individual possessing more than two complete sets of chromosomes (being polyploid), resulting from the hybridization between two or more distinct species, followed by chromosome doubling. This hybrid structural phenomenon combines non-homologous genomes, being extremely widespread in the plant kingdom (for instance, in wheat or cotton), where it ensures enhanced vigor and restored fertility.
- Allopolyploidy — The state, property, or structural phenomenon consisting of the presence of more than two chromosome sets originating from distinct species following interspecific hybridization. Allopolyploidy represents a major evolutionary engine in the plant kingdom, allowing the instantaneous emergence of new, fertile species reproductively isolated from their parents, combining the genetic advantages of both ancestral lines.
- Allosyndesis — A cytogenetic phenomenon or structural process consisting of the pairing (synapsis) during meiosis of non-homologous chromosomes originating from different parents or distinct species within a hybrid or allopolyploid organism. This type of atypical chromosomal association differs structurally from autosynapsis and plays an essential role in analyzing genomic reconfiguration and the degree of phylogenetic relationship between taxa.
- Amphidiploid — A polyploid organism or cell formed through the hybridization of two different species, followed by the doubling of the chromosome set, thus containing the complete diploid sets of both parental species. As an adjective, it describes a genetically stabilized genome, plant, or agricultural crop (such as triticale) capable of normal fertile reproduction because each chromosome finds its homologue during meiosis.
- Artioploid — An organism or polyploid cell that possesses an even number of complete chromosome sets (for example, tetraploid, hexaploid, octaploid); relating to this numerical condition of the genome. In plant and evolutionary genetics, this structure ensures higher meiotic stability compared to perissoploid (odd) forms, allowing normal fertility and regular genetic segregation.
- Autopolyploid — An organism or cell possessing more than two complete sets of homologous chromosomes (triploid, tetraploid, etc.), derived entirely from the multiplication of the genome of the same species, without the input of foreign genetic material. This structural genomic mutation phenomenon usually occurs through chromosome non-disjunction during meiosis or mitosis, serving as a major evolutionary driver in the plant kingdom, responsible for the emergence of varieties with enhanced productivity and resilience.
- Autopolyploidy — A structural genomic state or mutation characterized by the presence of more than two complete sets of homologous chromosomes within the cell nucleus, derived entirely from the same species due to endogenous duplication of genetic material without interspecific hybridization. This phenomenon occurs through the disruption of cell division (mitotic or meiotic non-disjunction) and plays a major role in the evolution and diversification of the plant kingdom, frequently causing morphological changes such as increased cell and organ size, as well as enhanced plant resilience.
- Autosyndesis — A genetic mechanism during meiosis in polyploid, particularly allopolyploid, organisms, characterized by the pairing (synapsis) and conjugation of homologous chromosomes derived from the same parental set or from the same ancestral species. This structural phenomenon differs from allosyndesis and plays a crucial role in maintaining genomic stability and determining inheritance patterns in complex plant hybrids.
- Autotetraploid — A polyploid organism or cell possessing four identical sets of chromosomes (4n), all derived through the multiplication or duplication of the base chromosome set of the same species, without interspecific hybridization. This structural genetic phenomenon, frequently encountered in the plant kingdom, often leads to plants with larger vegetative organs, bulkier flowers, and increased resistance to environmental factors.