The interplay between aridity and competition determines colonization ability, exclusion and ecological segregation in the heteroploid Brachypodium distachyon species complex.
New Phytol
; 215(1): 85-96, 2017 Jul.
Article
em En
| MEDLINE
| ID: mdl-28436561
ABSTRACT
A higher competitive advantage of polyploid plants compared with their parental diploids is frequently invoked to explain their establishment success, colonization of novel environments and cytotypic ecological segregation, yet there is scarce experimental evidence supporting such hypotheses. Here, we investigated whether differential competitive ability of species of the Brachypodium distachyon (Poaceae) species complex, a model system for genomic, ecological and evolutionary studies of temperate grasses, contributes to explaining their ecological segregation as well as their coexistence in diploid/allotetraploid contact zones. We conducted two field experiments in dry and humid localities to evaluate the tolerance to competition of diploids and allotetraploids in densely occupied environments, and to parameterize models of intra- and intercytotype competition as a mechanism for species exclusion/coexistence. We provide experimental evidence supporting the hypothesis that, under natural field conditions, allotetraploids have superior ecological success compared with one of their parental diploids in terms of both colonizing competitive habitats and intercytotypic competition, with the balance of intra/intercytotype competition favoring polyploid population establishment. These findings, together with previous data on ecogeographic segregation and adaptive response to water stress, suggest that the interplay between aridity and competitive outcome determines the ability to colonize competitive environments, the exclusion of diploids, especially in arid localities, and species geographic segregation.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Contexto em Saúde:
2_ODS3
Base de dados:
MEDLINE
Assunto principal:
Ploidias
/
Estresse Fisiológico
/
Brachypodium
Tipo de estudo:
Prognostic_studies
País/Região como assunto:
Europa
Idioma:
En
Revista:
New Phytol
Ano de publicação:
2017
Tipo de documento:
Article