Research interests

My research interests are plant/insect interactions, plant resistance, biological control, population biology, insect outbreaks and climate change.

Most of the research focuses on interactions between plants, insects and their natural enemies in two study systems:

(1) Insects on willows: leaf beetles (Col., Chrysomelidae), zoophytophagous bugs (Miridae, Anthocoridae) and syrphids.

(2) Forest insects: especially Neodiprion sertifer on Pinus spp. 

Insects on willows (1): Willows (Salix spp.) are grown as a renewable source of energy and among the many insects attacking willow plantations, leaf beetles are the most severe pests. Willow growth may be reduced by up to 40% when heavily defoliated. To use insecticides is not an option because of environmental and economical reasons. Thus, there is a need to control the beetles via resistant plants and biological control. Beside ongoing projects listed below, we are also conducting a long-term study of the population dynamics of leaf beetles and their natural enemies in planted and natural willow stands, as well as studies on plant responses to herbivory.

Forest insects (2): It is anticipated that insect outbreaks may become more frequent and severe in the future as a consequence of the ongoing climate change. However, our knowledge about the mechanisms triggering the outbreaks forest and other insects are still not very well known. Neodiprion sertifer is a major pest on pines, where the larvae may cause growth reductions due to defoliation by the larvae, showing typical outbreak dynamics. We run two projects that aim at answering why outbreaks occur and to what extent the risk for outbreaks is affected by climate change. They both link to the Mistra-project Future forests.

Ongoing research projects

• Resistance in willows against leaf beetles: searching for genetic markers 
• Enemy-enemy interactions and biological control 
• Forest insects and climate change: trophic interactions along climatic gradients  
• Characteristics of insect outbreaks and outbreak species 
• Causes and consequences of herbivore aggregation 
  
  

PhD students, Post docs, Master’s students

Teaching

Ecological methods

Links

Future Forests

Leaf beetles on willows 

SAMBA - SAlix Molecular Breeding Activities 

BACCARA

The Linnean Centre for Plant Biology Uppsala

Publications

CV

Selected recent publications

Lehrman, A., Torp, M., Stenberg, J.A., Julkunen-Tiitto, R. & Björkman, C. 2012. Estimating direct resistance in willows against a major insect pest, Phratora vulgatissima, by comparing life history traits. Entomologia Experimentalis et Applicata 144: 93-100. [PDF]

Ågren, G.I., Stenberg, J.A. & Björkman, C. 2012. Omnivores as plant bodyguards – A model of the importance of plant quality. Basic and Applied Ecology 13 (2012) 441–448. [PDF]

Moreau, G. & Björkman, C. 2012. Nonadditive interactions between trophic levels bias the appraisal of the strength of mortality factors. Population Ecology 54: 125-133. [PDF]

Koricheva, J., Klapwijk, M.J. & Björkman, C. 2012. Life history traits and host plant use in defoliators and bark beetles: implications for population dynamics. In: Insect Outbreaks Revisited ed. by Barbosa, P., Schultz, J.C. & Letourneau, D., Blackwell Publishing Ltd., Oxford, pp. 177-196.

Stenberg, J.A., Lehrman, A. & Björkman, C. 2011. Plant defence: feeding your bodyguards can be counter-productive Basic and Applied Ecology 12: 629-633. [PDF]

Björkman, C., Johansson, H. & Snäll, T. 2011. Spatial distribution of interacting insect predators: possible roles of intraguild predation and the surrounding habitat. Basic and Applied Ecology 12: 516-522.

Stenberg, J.A., Lehrman, A. & Björkman, C. 2011. Host-plant genotype mediates supply and demand of animal food in an omnivorous insect. Ecological Entomology 36: 442-449. [PDF]

Björkman, C. Bylund, H. & Berggren, Å. 2011. Insekter och klimatförändringar – vad vi vet, tror oss veta och inte vet. Fakta Skog Nr. 6. [PDF]

Bommarco, R., Miranda, F., Bylund, H. & Björkman, C. 2011. Insecticides suppress natural enemies and increase pest damage in cabbage. Journal of Economic Entomology 104: 782-791.

Miranda, F., Bylund, H., Grönberg, L., Larsson, L. & Björkman, C. 2011. Population density and killing capacity by predators of eggs and larvae of the diamondback moth in Nicaragua. Environmental Entomology 40: 333-341. [PDF]

Björkman, C., Bylund, H., Klapwijk,  M.K., Kollberg, I. & Schroeder, M. 2011. Insect pests in future forests: More severe problems? Forests 4: 474-485. [PDF]

Bognounou, F., Morton, R., Ayangma, S., Jonkers, L., Björkman, C., Bylund, H., Orians, C.M., Vega, A. & Odén, P.C. 2011. Stand structure of monocotyledons and dicotyledons in different succesional stages in Corcovado national park, Costa Rica. Bois et Forêts des Tropiques 307: 33-40. [PDF]

Berlin Kolm, S., Björkman, C., Bonosi, L., Ghelardini, L., Lehrman, A., Nordh, N.-E., Rönnberg-Wästljung, A.C., Samils, B., Stenberg, J.A., Stenlid, J., Weih, M., Åhman, I. & von Arnold, S. 2011. Nya salixsorter med modern växtförädlingsteknik. Fakta Jordbruk, Nr 3. [PDF]

Björkman, C., Kindvall, O., Höglund, S., Lilja, A., Bärring, L. & Eklund, K. 2011. High Temperature Triggers Latent Variation among Individuals: Oviposition Rate and Probability for Outbreaks. PLoS ONE 6(1): e16590. [PDF]

Björkman, C., Berggren, Å. & Bylund, H. 2011. Causes behind insect folivory patterns in latitudinal gradients. Journal of Ecology 99: 367-369 [PDF]

Dalin, P., Demoly, T., Kabir, Md. F. & Björkman, C. 2011. Global land-use change and the importance of zoophytophagous bugs in biological control: coppicing willows as a timely example. Biological Control 59: 6-12. [PDF]

Stenberg, J.A., Lehrman, A. & Björkman, C. 2010. Uncoupling direct and indirect plant defences: Novel opportunities for improving crop security in willow plantations. Agriculture, Ecosystems and Environment 139: 528-533. [PDF]

Berggren, Å., Björkman, C., Bylund, H. & Ayres, M. 2009. The distribution and abundance of animal populations in a climate of uncertainty. Oikos 118: 1121-1126. [PDF]

Dalin, P., Kindvall, O. & Björkman, C. 2009. Reduced Population Control of an Insect Pest in Managed Willow Monocultures. PLoS ONE 4(5): e5487. Doi:10.1371/journal.pone.0005487. [PDF]

Orians, C.M. & Björkman, C. 2009. Associational resistance to a tropical leaf-miner: does neighbour identity matter? Journal of Tropical Ecology 25: 551-554. [PDF]

Björkman, C., Gotthard, K. & Pettersson, M.W. 2009. Body size. In: Encyclopedia of Insects (2nd revised edition) ed. by Resch, V.H. & Cardé, R.T., Academic Press, San Diego, pp. 114-116. [PDF]

Björkman, C., Dalin, P. & Ahrné, K. 2008. Leaf trichome responses to herbivory in willows: induction, relaxation and costs. New Phytologist 179: 176-184. [PDF]

Weih, M., Didon, U.M.E., Rönnberg-Wästljung, A.-C. & Björkman, C. 2008. Integrated agricultural research and crop breeding: Allelopathic weed control in cereals and long-term productivity in perennial biomass crops. Agricultural Systems 97: 99-107.

Dalin, P., Ågren, J., Björkman, C., Huttunen, P. & Kärkkäinen, K. 2008. Leaf trichome formation and plant resistance to herbivory. In: Induced Plant Resistance to Herbivory ed. By Schaller, A., Springer, pp. 89-105. [PDF]

Dalin, P. & Björkman, C. 2006 Native insects colonizing introduced tree species – patterns and potential risks. In: Invasive Forest Insects, Introduced Forest Trees, and Altered Ecosystems: Ecological Pest Management in Global Forests of a Changing World. Springer, Dordrecht, pp. 63-77.