Term:
Chimera
Chimera
Definition:
An animal or a plant with genetically and morphologically different tissue on the same plant. The term is derived from Greek mythology and refers to a mythological animal composed of a lion, goat, and a serpent. Sometimes this term is also used to describe a plant derived from grafting, e.g., stems of Brazil nut trees grafted onto the root stock of another Brazil nut tree resulting in parts of the same tree with different genetic makeups. In Lecythidaceae, we use this term to describe the spontaneous occurence of anomalous flowers on a plant with normal flowers and assume that this difference is caused by a mutation.
An animal or a plant with genetically and morphologically different tissue on the same plant. The term is derived from Greek mythology and refers to a mythological animal composed of a lion, goat, and a serpent. Sometimes this term is also used to describe a plant derived from grafting, e.g., stems of Brazil nut trees grafted onto the root stock of another Brazil nut tree resulting in parts of the same tree with different genetic makeups. In Lecythidaceae, we use this term to describe the spontaneous occurence of anomalous flowers on a plant with normal flowers and assume that this difference is caused by a mutation.
Notes:
Known examples of chimeras in the Lecythidaceae are found in individuals with zygomorphic flowers that produce an abaxial extension of the staminal ring to produce a unilateral outgrowth called the ligule, which in a chimera suffers a mutation that produces abnormal flowers. The abnormal flowers are produced on the same tree as the result of the loss of abaxial dominace and, as a result, the staminal ring extends more-or-less equally around the circumferance of the staminal ring. This is an unusual occurrence in the Lecythidaceae and is most likely caused by a genetic mutation that results in the chimeric flowers having a different genetic makeup from the normal flowers. Another kind of chimera is when an individual with a single androecial hood sometimes produces flowers that have two androecial hoods.
Known examples of chimeras in the Lecythidaceae are found in individuals with zygomorphic flowers that produce an abaxial extension of the staminal ring to produce a unilateral outgrowth called the ligule, which in a chimera suffers a mutation that produces abnormal flowers. The abnormal flowers are produced on the same tree as the result of the loss of abaxial dominace and, as a result, the staminal ring extends more-or-less equally around the circumferance of the staminal ring. This is an unusual occurrence in the Lecythidaceae and is most likely caused by a genetic mutation that results in the chimeric flowers having a different genetic makeup from the normal flowers. Another kind of chimera is when an individual with a single androecial hood sometimes produces flowers that have two androecial hoods.