Ecotypic differentiation in Medicago polymorpha L. along an environmental gradient in central Chile. RAPDs studies show little genetic divergence

Paredes M.; BECERRA V.; Rojo, C; Del Pozo A.; Ovalle, C; Aronson J

Abstract

Burr medic (Medicago polymorpha) is distributed in a wide range of bioclimatic and edaphic conditions throughout the mediterranean-climate region of Chile. Previous studies on populations of M. polymorpha collected along this gradient revealed a remarkable ecotypic differentiation in many adaptive traits. Random amplified polymorphic DNA (RAPD) was used to evaluate genetic divergence in 36 accessions collected along the entire gradient. Three Australian commercial cultivars were also included in the study, of which two originated in Chile. The 40 RAPD primers used revealed a high degree of polymorphism and generated a total of 295 bands, of which 78% were polymorphic. Degrees of similarity, based on Nei's genetic distance, identified one group of accessions (22 of the 39 studied) with an index of similarity = 100% centered in the semiarid and arid zones of the study region. The remaining 17 accessions (from more mesic zones and one commercial cultivar) were more diverse. Only 91% similarity was found for the combined 39 accessions, indicating a low degree of genetic divergence. Biogeographical and life history strategy aspects of the results are discussed, including the notion of a suite of 'arid-adapted' characteristics arising in annual legumes under arid / semiarid conditions.

Más información

Título según WOS: Ecotypic differentiation in Medicago polymorpha L. along an environmental gradient in central Chile. RAPDs studies show little genetic divergence
Título según SCOPUS: Ecotypic differentiation in Medicago polymorpha L. along an environmental gradient in central Chile. RAPDS studies show little genetic divergence
Título de la Revista: EUPHYTICA
Volumen: 123
Número: 3
Editorial: SPRINGER, VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS
Fecha de publicación: 2002
Página de inicio: 431
Página final: 439
Idioma: English
URL: http://link.springer.com/10.1023/A:1015081631969
DOI:

10.1023/A:1015081631969

Notas: ISI, SCOPUS