Research interests

I am interested in ecological and evolutionary factors that structure plants, herbivores, and carnivores in agroecosystems and natural ecosystems. Most of my work is based on the Salix system.

Willow – leaf beetles – parasitoids/omnivores

I try to understand complex trophic interactions in a system based on three willow species: Salix cinerea (native), S. viminalis (naturalized), and S. dasyclados (alien). These willows are attacked by the detrimental blue willow beetle Phratora vulgatissima. The beetle is in turn attacked by the braconid parasitoid Perilitus brevicollis and the omnivorous bug Anthocoris nemorum, which also consume plant food.

Some questions that I investigate in this system are:

1. Is the parasitoid bottom-up controlled by host plant genotype? How can willow traits be manipulated to optimize parasitoid fitness? See project homepage.
2. Can density-dependent parasitism lead to herbivore outbreak? See project homepage.
3. Is herbivore egg clutch size under selection by omnivores (top-down), and by plant genotype (bottom-up)? Would the selection pressure on clutch size change following a climate change? See project homepage.
4. How is omnivore behavior and fitness affected by plant food quality and prey quality?

Other systems

A particularly interesting chrysomelid genus is Galerucella. When time allows I investigate trophic interactions involving the strawberry leaf beetle (G. tenella), the water lily leaf beetle (G. nymphaeae), and the brown willow beetle (G. lineola).

Publications

Stenberg JA. 2012. Density-dependent herbivory and biocontrol of the strawberry leaf beetle, Galerucella tenella. Acta Horticulturae, in press. [JAS19]

Stenberg JA, Stenberg JE. 2012. Herbivory limits the yellow water lily in an overgrown lake and in flowing water. Hydrobiologia, in press. [JAS18]

Baffoe KO, Dalin P, Nordlander G, Stenberg JA. 2012. Importance of temperature for the performance and biocontrol efficiency of the parasitoid Perilitus brevicollis (Hymenoptera: Braconidae) on Salix. BioControl, in press. [JAS17]

Lehrman A, Torp M, Stenberg JA, Julkunen-Tiitto R, Björkman C. 2012. Estimating direct resistance in willows against a major pest (Phratora vulgatissima) by comparing life history traits. Entomologia Experimentalis et Applicata, in press. [JAS16]

Stenberg JA. 2012. Effects of local vegetation and plantation age for the parasitoid Asecodes mento – a biocontrol agent in organic strawberry fields. Insect Science, in press. [JAS15]

Stenberg JA. 2012. Plant-mediated effects of different Salix species on the performance of the braconid parasitoid Perilitus brevicollis. Biological Control 60: 54 - 58. [JAS14]

Stenberg JA, Lehrman A & Björkman C. 2011. Plant defence: feeding your bodyguards can be counter-productive. Basic and Applied Ecology 12: 629 - 633. [JAS13]

Berlin Kolm S, Björkman C, Bonosi L, Ghelardini L, Lehrman A, Nordh N-E, Rönnberg-Wästljung AC, Samils B, Stenberg JA, Stenlid J, Weih M, Åhman I & von Arnold S. 2011. Nya salixsorter med modern växtförädlingsteknik. Fakta Jordbruk 1: 1 - 6. [JAS12]

Stenberg JA, Lehrman A & Björkman C. 2011. Host-plant genotype mediates supply and demand of animal food in an omnivorous insect. Ecological Entomology 36: 442 - 449. [JAS11]

Stenberg JA, Lehrman A & Björkman C. 2010. Uncoupling direct and indirect plant defences: novel opportunities for improving crop security in willow plantations. Agriculture, Ecosystems & Environment 139: 528 - 533. [JAS10]

Stenberg JA & Hambäck PA. 2010. Host species critical for offspring fitness and sex ratio for an oligophagous parasitoid: implications for host coexistence. Bulletin of Entomological Research 100: 735-740. [JAS9]

Stenberg JA & Axelsson EP. 2008. Host race formation in the Meadowsweet and Strawberry feeding leaf beetle Galerucella tenella.  Basic and Applied Ecology 9: 260 - 267. [JAS8]

Halitschke R, Stenberg JA, Kessler D, Kessler A & Baldwin IT. 2008. Shared signals - 'alarm calls' from plants increase apparency to herbivores and their enemies in nature. Ecology Letters 11: 24 – 34. [JAS7]

Stenberg JA, Hambäck PA & Ericson L. 2008. Herbivore-induced “rent rise” in the host plant may drive a diet breadth enlargement in the tenant. Ecology 89: 126 – 133. [JAS6]

Stenberg JA & Ericson L. 2008. Response to: Comment on 'Visual cues override olfactory cues in the host-finding process of the monophagous leaf beetle Altica engstroemi. Entomologia Experimentalis et Applicata 126: 87. [JAS5]

Stenberg JA & Ericson L. 2007. Visual cues override olfactory cues in the host-finding process of the monophagous leaf beetle Altica engstroemi. Entomologia Experimentalis et Applicata 125: 81–88. [JAS4]

Stenberg JA, Heijari J, Holopainen JK & Ericson L. 2007. Presence of Lythrum salicaria enhances the bodyguard effects of the parasitoid Asecodes mento for Filipendula ulmaria Oikos 116: 482 – 490. [JAS3]

Stenberg JA, Witzell J & Ericson L. 2006. Tall herb herbivory resistance reflects historic exposure to leaf beetles in a boreal archipelago age-gradient. Oecologia 148: 414 – 425. [JAS2]

Hambäck PA, Stenberg JA & Ericson L. 2006. Asymmetric indirect interactions mediated by a shared parasitoid: connecting species traits and local distribution patterns for two chrysomelid beetles. Oecologia 148: 475 – 481. [JAS1]