Profiles

Laura van Dijk

Laura van Dijk

Doktorand

View page in English
Arbetar vid Institutionen för ekologi miljö och botanik
Telefon 08-16 17 39
E-post laura.vandijk@su.se
Besöksadress Svante Arrhenius väg 20 A
Rum N 401
Postadress Institutionen för ekologi miljö och botanik 106 91 Stockholm

Om mig

I am a PhD student in the group of Ayco Tack, and my research is about plant-microbe-insect interactions (see below for background info). My fellow group-members are Pil Rasmussen (PhD student), Maria Faticov (PhD student), Alvaro Gaytan (PhD student) and Etsuko Nonaka (Postdoc), and my co-supervisor is Johan Ehrlen.

I obtained my masters-degree in Ecology and Biodiversity at Stockholm University. During my degree-project I performed research on the brain morphology of generalist and specialist Nymphalid butterflies (Department of Zoology).

Forskning

During my PhD project, I am focussing on the plant-insect-microbe interactions of 2 different plants: Anemone nemorosa (wood anemone) and Quercus robur (pedunculate oak). My main projects include:

  1. Studying the plant-insect-microbe interactions on oak
  2. The impact of single and multiple attacks of herbivorous insects and pathogens on defense-related pathways on oak
  3. The role of soil biota in mediating plant-pathogen-insect interactions on oak
  4. The impact of systemic pathogens on the insect and pollinator community associated with Anemone nemorosa

 

Background information: Plant-insect-microbe interactions

As primary producers, plants are at the base of the food-chain and act as a resource for many different organisms. Some of these organisms have a mutualistic interaction with their hostplant, but others are harmful: Herbivorous insects eat plant tissue, and pathogens make their hostplant sick. Even though plants may look like passive organisms, they are certainly not! Plants have evolved a complex immune system to fight these unwanted intruders. For example, the plant can produce certain antibiotic compounds or enzymes that will destroy an invading pathogen. Via plant volatiles, plants can even attract the natural enemies of their attacker, or “warn” neighbouring plants about the presence of plant-attackers. In their turn, plant-attackers have evolved ways to deal with these defending mechanisms of the plant. Thus, plants and their attackers are inflicted in an ongoing co-evolutionary battle.

Given the high abundance of plant-attackers in nature, co-occurrence of attackers on the same plant is a common event. Now, the attackers are not only dealing with the plant itself, but potentially also with one another. For example, a herbivorous insect is eating pathogen infected tissue, which may impact its performance. This in turn may also influence the preference of the insect towards either infected or healthy plants. Also, attackers can impact each other via the immune system of the plant: When a specific plant immune response is elicited by the first attacker, a second attacker can potentially benefit if not being sensitive to it.

How exactly the interaction between plant, microbe and insect will turn out is highly context dependent: Different combinations of species may impact each other differentially, and the interaction outcome also varies among different environments. Given the great diversity of plants, and of organisms that use plants as a host, the combinations of plant-based interactions are endless. Considering the diversity and complexity of interkingdom interactions and the relatively low number of studies performed on this subject, lots of knowledge gaps remain.... And lots of interesting opportunities for future research arise!

Publikationer

I urval från Stockholms universitets publikationsdatabas
  • 2017. Laura J. A. Van Dijk (et al.). Proceedings of the Royal Society of London. Biological Sciences 284 (1866)

    An ovipositing insect experiences many sensory challenges during her search for a suitable host plant. These sensory challenges become exceedingly pronounced when host range increases, as larger varieties of sensory inputs have to be perceived and processed in the brain. Neural capacities can be exceeded upon information overload, inflicting costs on oviposition accuracy. One presumed generalist strategy to diminish information overload is the acquisition of a focused search during its lifetime based on experiences within the current environment, a strategy opposed to a more genetically determined focus expected to be seen in relative specialists. We hypothesized that a broader host range is positively correlated with mushroom body (MB) plasticity, a brain structure related to learning and memory. To test this hypothesis, butterflies with diverging host ranges (Polygonia c-album, Aglais io and Aglais urticae) were subjected to differential environmental complexities for oviposition, after which ontogenetic MB calyx volume differences were compared among species. We found that the relative generalist species exhibited remarkable plasticity in ontogenetic MB volumes; MB growth was differentially stimulated based on the complexity of the experienced environment. For relative specialists, MB volume was more canalized. All in all, this study strongly suggests an impact of host range on brain plasticity in Nymphalid butterflies.

Visa alla publikationer av Laura van Dijk vid Stockholms universitet

Senast uppdaterad: 17 april 2018

Bokmärk och dela Tipsa