Introgression (from Latin introgredior , "to come in, to enter"), also known as introgressive hybridization , describes the movement of a gene , chromosome , chromosome segment or genome from one species or subspecies to another.
This can happen “by chance” through a historical, naturally occurring mating of an individual from one population with individuals from another population. The principle is considered to be an important factor in the evolution of aquatic species such as B. in freshwater fish discussed.
Humans use the principle and the result to obtain high-performance breeds that carry a certain characteristic through (natural) hybridizations with conventional displacement breeding . Introgression is usually achieved through various backcrossing processes in order to eradicate unwanted side effects. The genes added to the species mostly come from related wild species or from species from closely related genera .
Modern embryo rescue and somatic hybridization processes have given the introgression of foreign genes in cultivated plants a new impetus. Introgression has long been of great practical importance in cereal breeding, especially wheat .
- Rolf H. Schlegel : Dictionary of Plant Breeding , 2nd ed., Taylor & Francis, USA 2009, ISBN 9781439802427 .
- Rolf H. Schlegel: Secale cereale L. A younger crop plant with bright future . In: Ram J. Sing, P. Jauhar (Eds.): In: Cereals (Genetic Resources. Chromosome Engineering, and Crop Improvement; 2). CRC Press, Boca Raton 2006, ISBN 0-8493-1430-5 , pp. 365-394.
- Rolf H. Schlegel: Concise Encyclopedia of Crop Improvement. Institutions, Persons, Theories, Methods, and Histories . Haworth Press, New York 2007, ISBN 978-1-56022-146-3 , p. 331.
- Rolf H. Schlegel: Current list of wheats with rye and alien introgression . V08-11 (2011), pp. 1-14.