Details

Autor(en) / Beteiligte

• Shelby, Natasha
• Hulme, Philip E.
• van der Putten, Wim H.
• McGinn, Kevin J.
• Weser, Carolin
• Duncan, Richard P.

Titel

No difference in the competitive ability of introduced and native Trifolium provenances when grown with soil biota from their introduced and native ranges

Ist Teil von

• AoB plants, 2016-01, Vol.8

Ort / Verlag

England: Oxford University Press

Erscheinungsjahr

2016

Quelle

Free E-Journal (出版社公開部分のみ）

Beschreibungen/Notizen

• This biogeographic study tested the evolution of increased competitive ability (EICA) hypothesis—a compelling explanation for why plants become invasive. We measured growth rates and the competitive ability of three Trifolium species sourced from their native (Spain and the UK) and New Zealand-naturalised ranges when grown with rhizosphere microbiota from each range. Although EICA was not supported (naturalised plants were not more competitive) the differences in plant competitive ability when grown with different rhizosphere microbial communities illustrate that soil microbiota affect plant growth and competition. The work illustrates an important finding: growth of singly-grown plants doesn't always predict competitive ability. The evolution of increased competitive ability (EICA) hypothesis could explain why some introduced plant species perform better outside their native ranges. The EICA hypothesis proposes that introduced plants escape specialist pathogens or herbivores leading to selection for resources to be reallocated away from defence and towards greater competitive ability. We tested the hypothesis that escape from soil-borne enemies has led to increased competitive ability in three non-agricultural Trifolium (Fabaceae) species native to Europe that were introduced to New Zealand in the 19th century. Trifolium performance is intimately tied to rhizosphere biota. Thus, we grew plants from one introduced (New Zealand) and two native (Spain and the UK) provenances for each of three species in pots inoculated with soil microbiota collected from the rhizosphere beneath conspecifics in the introduced and native ranges. Plants were grown singly and in competition with conspecifics from a different provenance in order to compare competitive ability in the presence of different microbial communities. In contrast to the predictions of the EICA hypothesis, we found no difference in the competitive ability of introduced and native provenances when grown with soil microbiota from either the native or introduced range. Although plants from introduced provenances of two species grew more slowly than native provenances in native-range soils, as predicted by the EICA hypothesis, plants from the introduced provenance were no less competitive than native conspecifics. Overall, the growth rate of plants grown singly was a poor predictor of their competitive ability, highlighting the importance of directly quantifying plant performance in competitive scenarios, rather than relying on surrogate measures such as growth rate.