Conceptually, our lab focuses on the ecology and evolution of plant-based food webs within a spatially and temporally variable world. More specifically, we have a strong interest in:

  • Plant-microbe-insect interactions
  • Belowground-aboveground interactions among insects and microbes
  • The spatial ecology of microbial and insect food webs (‘metacommunity dynamics’)
  • The impact of climate on the phenology of plant-based food webs
  • Eco-evolutionary dynamics between plants, insects and microbes
  • The relationship between climate, pests and diseases, and smallholder farmer’s livelihood

To pursue those conceptual questions, we have some favorite study systems.

A multitrophic microbial and insect food web on oak

During my PhD, I (Ayco) fell in love with the leaf miners and gallers on oak trees, which have proofed to be an excellent study system for studies on the spatial ecology of multitrophic insect communities. It turned out that the microbial community on oak is as diverse, important and intriguing, and the white fluff on the oak leaves is a cryptic community of pathogen species, attacked themselves by fungal hyperparasites. We are now interested in the interactions between the insect and microbial food webs, and how climate may influence these interactions. For this, we have reared tens of thousands of insects, sequenced thousands of microbial samples, and conducted field heating experiments. Since 2003, a group of scientists and fieldworkers travels to the island of Wattkast in southwestern Finland each autumn, to search through a zillion leaves in search of leaf miners, gallers and powdery mildew on a subset of the c. 2000 oak trees on the island. This unique long-term and spatially explicit survey of the oak-associated insects and microbes has provided great insights in natural metacommunity dynamics, placed experimental findings into context, and continues to stimulate new, field-based questions. We also made an animation movie and other teaching material related to the oak food web:

The relationship between climate, biodiversity, coffee diseases and yield

A fair share of all our science depends on coffee. It also provides employment to a whopping 125 million people across the world, including many farmers in developing countries. In this project, we employ our insights in climate, biodiversity, pests and diseases for an applied aim: a sustainable and diverse agroforestry system for coffee. Where sustainable refers both to the conservation of biodiversity and a stable income for the smallholder farmer. Our studies take place within the area of origin of Arabica coffee, and our permanent field sites span the range from coffee growing under the natural forest canopy to more intensively managed plantation coffee. Our main focus is on coffee genetic diversity, metabolomics, multi-year pest and disease dynamics, plant diversity and the social and economic conditions of the smallholder farmers. More recently, we placed hundreds of dataloggers to investigate the impact of climate on coffee diseases and crop yield, and the potential for farmers to mitigate or adapt to climate change.

Community dynamics of fungal diseases on the wood anemone

I am fascinated by the spatial and eco-evolutionary dynamics of host-parasite interactions. We do lack some generality though: many of the existing studies have (for good reasons!) focused on single pathogen species, and on non-systemic diseases with high extinction-colonization rates. In this project, we aim to uncover the distribution and infection dynamics of four fungal pathogens in natural populations of one of Sweden’s charismatic forest herbs: the wood anemone (Anemone nemorosa). Specifically, we monitor the distribution and abundance of natural populations of the wood anemone and its fungal pathogens both spatially and temporally in the Tullgarn area since 2017. Furthermore, we use long-term experimental studies to investigate whether and how plants cure themselves from fungal diseases, how the diseases interact, how effective the diseases are in colonizing new host plants, and how fungal diseases affect the herbivore and pollinator community of the wood anemone.

Belowground beneficial and antagonistic microbes on perennial herbs

Plants are host to a wealth of microbes, both beneficial and antagonistic, and these may be found both on aboveground plant structures and in the roots. In our work, we have been focusing on the patterns and drivers of plant-associated microbes: their multi-scale spatial distribution, the impact of dispersal limitation, and the role of the abiotic and biotic environment, and the aboveground consequences. To answer these questions we have mainly used the plant ribwort plantain (Plantago lanceolata) and its associated root fungi, stained coffee roots in Ethiopia to assess arbuscular mycorrhizal colonization, and sequenced the fungal and bacterial root microbial community of several arctic plant species found in northeastern Greenland.

The Insect Biome Atlas

The Insect Biome Atlas (IBA) is a large-scale insect collection project taking place in Sweden and Madagascar. The main aim of the project is to describe in detail the insect faunas of these two biologically and geologically very different countries. Insects were collected using Malaise traps: 200 malaise traps in Sweden and 50 in Madagascar. In Sweden, the traps were managed by over 100 volunteers, which makes this project one of the largest citizen science projects to take place in Scandinavia. Several other types of samples and ecological measurements were collected at the trap sites to gather a full understanding of the ecological roles of the organisms that comprise the insect biome in these countries. The identification of all insects and the organisms they interact with, such as pathogens as well as symbiotic fungi and bacteria, will be achieved using non-destructive massive parallel sequencing. The project is a collaboration between Fredrik Ronquist (The Swedish Museum of Natural History), Ayco Tack (Stockholm University), Tomas Roslin (Swedish Agricultural University) and Anders Andersson (KTH/SciLifeLab). The project is funded by the Knut and Alice Wallenberg Foundation.