Aquaculture of Triploid

Crassostrea ariakensis
in Chesapeake Bay

A Symposium Report

Aneuploid gametes. Germ cells (egg or sperm) that have more or less than a complete complement of chromosomes. Chromosomes in most living organisms come in two sets, and gametes generally only have one set. For example, a set of human chromosomes has 23 and a set of oyster chromosomes has 10.

Benthic. Those biological and chemical processes associated with the seabed.

Biosecurity. In the context of triploid C. ariakensis, biosecurity refers to measures taken to minimize the likelihood of stocking this species in the Bay, such as rampant reproduction or the introduction of pathogens or pests.

Broodstock. Adult organisms that yield offspring.

Cell culture. The cultivation of cell populations isolated from tissues of plants or animals, artificially in the laboratory.

Diploid. A chromosome state in which each chromosome is represented twice (2N). (In animals with sex chromosomes, the sex chromosomes are not necessarily present in two copies.)

Electron microscopy. High resolution microscopy obtained by using atomic particles to illuminate the subject. Electron microscopy often is used in detection of viruses.

Euploid gametes. Germ cells (egg or sperm) that contain an even multiple of chromosome sets, i.e., one set in gametes from diploids, two sets in gametes from tetraploids.

Gamete sink. In the context of this report, gametes of two species that combine to form inviable hybrid embryos, thereby wasting reproductive effort of both.

Gelatinous zooplankton. Invertebrate animals of the phylum Coelenterata, including jellyfish, comb jellies, hydras, sea anemones and salps.

Hazard. An undesired outcome, for instance, an accidental introduction of a new oyster disease.

Molecular techniques. Methods of examining genetic relationships using traits at the DNA level. For example, oysters can be identified to species based on unique sequences of nucleic acids that are revealed by isolating, cutting, amplifying, and visualizing DNA fragments.

Pelagic. Those biological and chemical processes associated with the water column.

Protozoan. Any single-celled member of the animal kingdom in the phylum Protozoa.

Ploidy. The number of chromosome sets.

Polyploidy. A chromosome number that is a multiple of the normal diploid number.

Reversion. In the context of triploid C. ariakensis, the gradual progressive loss of chromosomes from polyploid individuals, producing individuals with cells of more than one ploidy.

Risk. The probability of a hazard becoming realized when exposed to a causal agent.

Tetraploid. Having four sets of chromosomes in the nucleus.

Triploid. Having three sets of chromosomes in the nucleus.