Integrating novel chemical weapons and evolutionarily increased competitive ability in success of a tropical invader.
New Phytol
; 205(3): 1350-1359, 2015 Feb.
Article
de En
| MEDLINE
| ID: mdl-25367824
ABSTRACT
The evolution of increased competitive ability (EICA) hypothesis and the novel weapons hypothesis (NWH) are two non-mutually exclusive mechanisms for exotic plant invasions, but few studies have simultaneously tested these hypotheses. Here we aimed to integrate them in the context of Chromolaena odorata invasion. We conducted two common garden experiments in order to test the EICA hypothesis, and two laboratory experiments in order to test the NWH. In common conditions, C. odorata plants from the nonnative range were better competitors but not larger than plants from the native range, either with or without the experimental manipulation of consumers. Chromolaena odorata plants from the nonnative range were more poorly defended against aboveground herbivores but better defended against soil-borne enemies. Chromolaena odorata plants from the nonnative range produced more odoratin (Eupatorium) (a unique compound of C. odorata with both allelopathic and defensive activities) and elicited stronger allelopathic effects on species native to China, the nonnative range of the invader, than on natives of Mexico, the native range of the invader. Our results suggest that invasive plants may evolve increased competitive ability after being introduced by increasing the production of novel allelochemicals, potentially in response to naïve competitors and new enemy regimes.
Mots clés
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Climat tropical
/
Chromolaena
/
Évolution biologique
/
Espèce introduite
/
Allélopathie
/
Modèles biologiques
Type d'étude:
Prognostic_studies
Langue:
En
Journal:
New Phytol
Sujet du journal:
BOTANICA
Année:
2015
Type de document:
Article
Pays d'affiliation:
Chine