The differential impact of a native and a non-native ragwort species (Senecioneae) on the first and second trophic level of the rhizosphere food web

TY - JOUR

T1 - The differential impact of a native and a non-native ragwort species (Senecioneae) on the first and second trophic level of the rhizosphere food web

AU - Harkes, Paula

AU - Verhoeven, Ava

AU - Sterken, Mark G.

AU - Snoek, L. Basten

AU - van den Elsen, Sven J.J.

AU - Mooijman, Paul J.W.

AU - Quist, Casper W.

AU - Vervoort, Mariëtte T.W.

AU - Helder, Johannes

N1 - ; Data archiving: data archived in Dryad

PY - 2017

Y1 - 2017

N2 - © 2017 Nordic Society Oikos. Whereas the impact of exotic plant species on above-ground biota is relatively well-documented, far less is known about the effects of non-indigenous plants on the first and second trophic level of the rhizosphere food web. Here, rhizosphere communities of the invasive narrow-leaved ragwort Senecio inaequidens and the native tansy ragwort Jacobaea vulgaris, co-occurring in three semi-natural habitats are compared. For both species, two life stages were taken into consideration. Quantitative PCR assays for the analyses of bacterial and fungal communities at a high taxonomic level were optimized, and it was investigated whether changes in the primary decomposer community were translated in alterations in bacterivorous and fungivorous nematode communities. In contrast to J. vulgaris, small but significant reductions were observed for Actinobacteria and Bacteroidetes (both p < 0.05) in case of the invasive S. inaequidens. More pronounced changes were detected for the overall nematode community density, and, more specifically, for the bacterivorous genus Anaplectus and the family Monhysteridae (both p < 0.05), as well as the necromenic Pristionchus (p < 0.001). At high taxonomic level, no differences were observed in fungal rhizosphere communities between native and non-native ragwort species. The impact of plant developmental stages on rhizosphere biota was prominent. The overall bacterial and fungal biomasses, as well as a remarkably consistent set of constituents (Actinobacteria, α- and β-Proteobacteria and Bacteroidetes) were negatively affected by plant stage for both ragwort species. Although later developmental stages of plants generally coincided with lower levels for individual nematode taxa, densities of the fungivorous genera Diphtherophora and Tylolaimophorus remain unaltered. Hence, even at a high taxonomic level, differential effects of native and non-native ragwort could be pinpointed. However, plant developmental stage has a more prominent impact and this impact was similar in nature for both native and non-native ragwort species.

AB - © 2017 Nordic Society Oikos. Whereas the impact of exotic plant species on above-ground biota is relatively well-documented, far less is known about the effects of non-indigenous plants on the first and second trophic level of the rhizosphere food web. Here, rhizosphere communities of the invasive narrow-leaved ragwort Senecio inaequidens and the native tansy ragwort Jacobaea vulgaris, co-occurring in three semi-natural habitats are compared. For both species, two life stages were taken into consideration. Quantitative PCR assays for the analyses of bacterial and fungal communities at a high taxonomic level were optimized, and it was investigated whether changes in the primary decomposer community were translated in alterations in bacterivorous and fungivorous nematode communities. In contrast to J. vulgaris, small but significant reductions were observed for Actinobacteria and Bacteroidetes (both p < 0.05) in case of the invasive S. inaequidens. More pronounced changes were detected for the overall nematode community density, and, more specifically, for the bacterivorous genus Anaplectus and the family Monhysteridae (both p < 0.05), as well as the necromenic Pristionchus (p < 0.001). At high taxonomic level, no differences were observed in fungal rhizosphere communities between native and non-native ragwort species. The impact of plant developmental stages on rhizosphere biota was prominent. The overall bacterial and fungal biomasses, as well as a remarkably consistent set of constituents (Actinobacteria, α- and β-Proteobacteria and Bacteroidetes) were negatively affected by plant stage for both ragwort species. Although later developmental stages of plants generally coincided with lower levels for individual nematode taxa, densities of the fungivorous genera Diphtherophora and Tylolaimophorus remain unaltered. Hence, even at a high taxonomic level, differential effects of native and non-native ragwort could be pinpointed. However, plant developmental stage has a more prominent impact and this impact was similar in nature for both native and non-native ragwort species.

KW - national

UR - https://doi.org/10.5061/dryad.t4313

U2 - 10.1111/oik.04530

DO - 10.1111/oik.04530

M3 - Article

SN - 0030-1299

VL - 126

SP - 1790

EP - 1803

JO - Oikos

JF - Oikos

IS - 12

ER -