Autoplodija

Autoplodija, or autopolyploidy, is a form of polyploidy in which an organism contains more than two complete sets of chromosomes, with all sets originating from the same species. This contrasts with alloplodija (allopolyploidy), where the chromosome sets come from different species. In autoplodiji, the chromosome sets are highly similar in gene content, which can influence how they pair during meiosis.

Formation can occur in several ways. Genome doubling in a diploid cell (autoduplication), the fusion of unreduced 2n gametes, or endoreduplication in somatic tissues that contribute to reproduction can create autopolyploids. Resulting cytotypes can include triploid (3n), tetraploid (4n), and higher levels (6n, 8n, etc.).

Meiosis and genetics in autoploids often involve multivalent chromosome pairing (such as triplets or quadrivalents) rather than strict bivalent pairing, which can produce balanced or unbalanced gametes and often reduces fertility. Some autoploids nevertheless show stable, disomic-like inheritance and fertility across generations, depending on the degree of chromosome similarity and pairing behavior.

Consequences and uses: Autoploidia is common in plants and can lead to larger cells and organs, altered physiology, and potential ecological differentiation. It is an important mechanism of rapid speciation in plants. In breeding, chromosome doubling is sometimes induced chemically (for example with colchicine) to create autopolyploid lines for crops, which can enhance traits such as fruit size or stress tolerance.

See also: Polyploidy, Autopolyploid, Allopolyploidy.