Land use effects on insect root herbivores and their interactions with arbuscular mycorrhiza

Insect root herbivores and arbuscular mycorrhizal fungi (AMF) have been demonstratedto be important drivers of plant diversity and productivity. Nonetheless, there is anextreme lack of knowledge about the factors influencing their abundance and diversity.Since the quality of plant tissue for herbivores differs between plant species, we predict that changes in the composition of plant communities affect insect root herbivores. Insect root herbivores on the other hand are likely to affect AMF communities by altering the availability of photosynthetically fixed carbon. Ultimately, changes in AMF communities caused byinsect root herbivory may feed back on the structure of plant communities. The Biodiversity Exploratories provide an excellent opportunity to explore these reciprocal relationships between plant diversity, root herbivores and AMF along gradients in land use intensity.

Hypotheses

Our main hypotheses are (1) that differences in plant diversity and soilnutrient level, brought by gradients in land use intensity, influence the abundance anddiversity of insect root herbivores, (2) that insect root herbivory influences the abundance and diversity of AMF and (3) that changes in the abundance and diversity of AMF caused by insect root herbivory feed back on the structure of plant communities

Picture: The graph shows correlations between plant diversity, soil insects and mycorrhiza. — Fig. 1: Interactions between land use induced plant diversity, insect root feeders and arbuscular mycorrhizal fungi

Methods

Additionally to observational field work (hypothesis 1), we will conduct greenhouse experiments (hypotheses 2 and 3) to obtain a deeper understanding on how these soil organism groups interact with each other.

Publications

Species specific responses of common grassland plants to a generalist root herbivore (Agriotes spp. larvae)

Sonnemann I., Baumhaker H., Wurst S.(2012): Species specific responses of common grassland plants to a generalist root herbivore (Agriotes spp. larvae). Basic and Applied Ecology 13, 579–586. doi: 10.1016/j.baae.2012.09.010

Effekte unterschiedlicher Wurzelherbivore auf Mykorrhizierung und Wachstum verschiedener Pflanzen

Baumhaker H.(2010): Effekte unterschiedlicher Wurzelherbivore auf Mykorrhizierung und Wachstum verschiedener Pflanzen. Bachelor thesis, Freie University Berlin

Einfluss von Elateriden Larven auf die Mykorrhizierung von Plantago lanceolata in einer Grasland-Pflanzengemeinschaft

Beutel M.(2010): Einfluss von Elateriden Larven auf die Mykorrhizierung von Plantago lanceolata in einer Grasland-Pflanzengemeinschaft. Bachelor thesis, Freie University Berlin

Einfluss von Elateriden Larven auf die extraradikale AMF-Abundanz in einer Grasland-Pflanzengemeinschaft

Hanauer N.(2010): Einfluss von Elateriden Larven auf die extraradikale AMF-Abundanz in einer Grasland-Pflanzengemeinschaft. Bachelor thesis, Freie University Berlin

Scientific assistants

Alumni

Prof. Dr. Susanne Wurst

Alumni

Dr. Ilja Sonnemann