Sex-biased predation in dioecious willow- The long reach of plant genes

Johan A. Stenberg

Md. Faisal Kabir, Kim Karlsson Moritz & Johan A. Stenberg

Plants provide carnivores with:

ResourcesInformation

Extended phenotype:All effects that genes have on their environment

Study system: dioecious willow

Salix cinerea

♂ ♀

Phratora vulgatissima

Anthocoris nemorum

Sex-biased insect densities in the field

2011 20130

1

2

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Male

Female

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Male

Female

P.

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Sex-biased predation in the field

Male Female

n = 22 plants n = 22 plants

0hrs 24hrs 48hrs 72hrs 96hrs 120hrs 144hrs0

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Female

Male

Sex-biased herbivore performance?

Male Female0

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Sex-biased herbivore preference?

Male Female0

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Sex-biased predator performance?

Male Female0

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(day

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Sex-biased predator preference?

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Summary + discussion1. Female plants harbor higher densities of the herbivore

and its omnivorous predator in the field.

2. The herbivore prefers female plants despite high predation pressure on females.

3. The omnivorous predators perform better on male plants.

4. The herbivore probably prefers female plants as the arena for interactions with the predator since female plants are suboptimal for the predator.

Tentative conclusions1. The insects preference for female plants seems to be

adaptive.

2. The extended phenotype of Salix cinerea structures the ecological interactions between herbivores and predators.

Work continues in PhD project

• 30 fields.• 20 male, 20 female genotypes.• Male, female and mixed fields.• Interactions within fields.

• Effects on neighbouring strawberries.

Kim Karlsson Moritz

AcknowledgementsKwabena BaffoeChrister BjörkmanTina BoddumPeter DalinKarin EklundRobert GlinwoodRiitta Julkunen-TiittoFaisal KabirKim Karlsson MoritzSharmin KawsharAnna LehrmanGöran NordlanderColin OriansAmy ParachnowitschJörg StephanMikaela TorpGöran Ågren

The Swedish Research Council Formas The Swedish Research Council VR The Swedish Energy Agency The Royal Swedish Academy of Agriculture and Forestry NL-faculty (SLU) The Foundation in Memory of Oscar and Lili Lamm Carl Trygger Foundation

Importance for short rotation coppice - Plantations are unisexual.- Choosing the ’right’ plant sex is an important part of IPM.