Jackson Estuarine Laboratory

Induced chromosome number variation in the winter flounder


The karyotype of the winter flounder was established from hatchery produced larvae, and the diploid number of chromosomes found to be 2n = 48. In an attempt to induce triploid development, cold shocking fertilized eggs significantly changed the distribution of chromosome counts among larvae compared to the diploid control, but triploid development was not demonstrated. Likewise, irradiation of sperm by UV resulted in variable chromosome inactivation, as indicated by the range of chromosome numbers in mono-ploid and gynogenetic treatment embryos, but cold shocking was not successful in producing gynogenetic larvae. Chromosomal, as well as morphological, evidence for monoploid development was found. Chromosome counts in monoploid treatments can be used as checks for success of gynogenetic techniques, and analysis at early stages of development can monitor potential chromosome variation, including polyploid/diploid mosaicism.

Publication Date


Journal Title

Journal of Heredity

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Copyright © 1981, Oxford University Press