| 释义 |
introˈgression|-ˈgrɛʃən|
[f. L. type *intrōgressiōn-em, f. introgredī to step in.]
1. A going or coming in, entrance, incoming.
1656Blount Glossogr., Introgression (introgressus), a going in. 1845Stocqueler Handbk. Brit. India (1854) 136 Instead of being jostled out of employment by the introgression of Europeans.
2. Biol. The transfer of a small amount of genetic material from one (usu. plant) species to another as a result of hybridization between them and repeated back-crossing.
1938Anderson & Hubricht in Amer. Jrnl. Bot. XXV. 399 We conclude that there is a strong introgression of T. canaliculata into T. occidentalis. 1950G. L. Stebbins Variation & Evolution in Plants vii. 265 In this instance, therefore, frequent interspecific hybridization is not accompanied by introgression of genes across the barrier formed by partial sterility of the F1 hybrid. 1963Lewis & John Chromosome Marker iv. iv. 373 Low sterility and open pollination will favour introgression. 1971V. Grant Plant Speciation iv. 52 If the introgression goes far enough, it may obliterate the morphological and ecological distinctions between the original species. |