Chemical Ecology - Agriculture

Last changed: 02 March 2020
Spodoptera littoralis (Cotton leaf worm larvae

Chemically mediated interactions between plants and insects are central in many habitats, both natural ones and those influenced by human activities. The aim of our research is to establish sustainable control methods for pest insects of socioeconomically important crops.

The group mainly studies multitrophic ecological interactions between plants and herbivorous insects, where chemical signals are essential. We combine and integrate ecological, evolutionary, physiological and applied assays with in-depth expertise in chemical analysis to identify behaviourally and physiologically active olfactory signals and to gain a comprehensive understanding of how they influence our study systems.

The research includes different aspects of ecology that affect both host plant and mate choice in insects. Important research is also done on preserving insect biodiversity, and on monitoring and controlling pests. Our aim is to produce novel and interesting scientific advancements, as well as applicable knowledge that responds to societal needs and sustainable development.

Current projects

Host plant selection in moths

Reliable host plant recognition

Accurate identification of important resources involves both reliable discrimination between suitable and unsuitable resources, and the ability to handle natural variation in the emittance of sensory cues from these resources through generalisation. In this project we will study how odorant compound composition and the ratios between the compounds interact to allow host plant discrimination and functional generalization in the Cotton leaf worm, Spodoptera littoralis. Furthermore, we will investigate how these processes are affected by innate characteristics as well as olfactory-guided phenotypic plasticity, both in an intra- and a trans-generational context.

Researchers on the project

Peter Anderson (Prof.) 

Axel Rösvik (PhD student)

Marie Bengtsson (Prof.)

Exploring transgenerational plasticity in insect host plant selection

This project will study transgenerational phenotypic plasticity connected to host plant utilisation and explore underlying physiological and genetic mechanism in the Cotton leaf worm, Spodoptera littoralis. It will study changes in behavioural, ecological and physiological traits and correlate them with a mapping and comparison of the gut bacterial community (microbiome) of offspring and investigations determining epigenetic inheritance factors involved. The project aims to improve our understanding about plant-insect interactions where phenotypic plasticity can mediate fast adaptation and more accurate decision-making, and new insights of how agricultural pests can spread and rapidly establish in new environments.

Researchers on the project

Peter Anderson (Prof.) 

Axel Rösvik (PhD student)

Kristina Karlsson Green 

Mattias Larsson (docent)

Alumni:

Ben Houot

Patrick L homme

Mohammed Khallaf

Impact of host plant range on pesticide resistance evolution

An increased number of crop pest insects have developed resistance to the available insecticides and recent research has highlighted that generalist insect species may readily develop resistance as they are pre-adapted to tolerate and resist a wide array of plant chemical defences. In this project, we compare pesticide resistance evolution in the generalist species Spodoptera littoralis with the specialist species S. picta. In addition, to understand if pesticide resistance also can lead to an increased ability to overcome host plant defences, we study the potential for host plant range expansion following selection for pesticide resistance.

Reserachers involved:

Kristina Karlsson Green

Audrey Bras

Peter Anderson

Collaborators: 

Amit Roy (Czech University of Life Sciences Prague)

Kazuei Mita

Phenotypic plasticity during range expansion

When a species disperse into new areas, phenotypic plasticity may aid as a buffer against novel environmental selection pressures. As a range expanding species likely encounter several different environmental factors, this project aims to investigate if range margin populations are more plastic than core populations in general, i.e. in several different traits. To answer this question we compare plasticity in host plant choice, immune function and temperature tolerance in different populations of Spodoptera littoralis.

Researchers involved:

Peter Anderson (Prof.) 

Kristina Karlsson Green

Ecological immunity

Immune function is a costly trait and individuals often have a context dependent investment in immune function. Spodoptera lilttoralis has previously been extensively used as a model species for immune function studies and in our project we investigate the effect of natural host plant diet on immune function and the relation between immune investment and host plant selection in this species.

Researchers involved:

Kristina Karlsson Green 

 

Pest management in oilseed rape

Interactions between insects and oilseed rape – dynamic consequences in the wake of the Brassica pod midge as a novel emerging pest

Brassica pod midge damage
Larvae from Brassica pod midge (Dasineura brassicae) in pod

The Brassica pod midge Dasineura brassicae, in combination with its facilitator, the seed pod weevil Ceutorrhynchus assimilis, has recently emerged as a serious pest of oilseed rape in Sweden. This study aims to develop novel IPM strategies and to find efficient attractants to monitor D. brassicae. We will also characterize environmental and landscape factors which cause population buildup and spread of the two pests. Finally, the project will investigate how the new ecological situation and management strategies affect populations of other pest insects, natural enemies and pollinators of the oilseed rape system.

Researchers on the project:

Peter Anderson (Prof.) 

Mattias Larsson (docent)

Spatiotemporal dynamics of insect pests and pathogens in agroecological systems – using spatial planning to prevent population buildup and crop damage

Crop distribution in the landscape most likely constitutes an important factor for outbreaks of e. g.  insect pests and pathogens. The project will link pest population dynamics to the sequential distribution patterns of crops in the landscape at different spatial scales. The aim is to improve risk predictions and decision systems and allow forward planning of crop rotation systems to avoid population buildup of pest organisms. Furthermore, to develop a user-friendly application to predict landscape-wide distributions of pests and to make predictions about how to optimize crop distribution to minimize the effects of pests.

Researchers on the project:

Peter Anderson (Prof.) 

Mattias Larsson (docent)

PheroBio at SLU

PheroBio at SLU

Pyrrhidium sanguineum/beetle trap
Showing the beetle Pyrrhidium sanguineum and a pheromone trap used to collect the insects.

We are currently facing major environmental challenges where rapid landscape and climate changes are putting species and whole ecosystems at the risk of extinction. Some of the most sensitive organisms are the insects, who often are among the first affected by disturbances in an ecosystem. In the PheroBio project at SLU we utilize pheromones (sexual attractant chemicals) and other semiochemicals for large-scale trapping and monitoring of threatened insects with the goal of obtaining new insights into their ecology and conservation requirements. We work with an expanding portfolio of rare insects from both agricultural and forest habitats such as burnet moths, click beetles and longhorn beetles. Our research is focused on two main objectives:

 -          Identify sex pheromones and aggregation-sex pheromones of rare insects and develop methods for   systematic and efficient monitoring of biodiversity.

-          Utilize pheromone-based trapping for large-scale studies focusing on the relationship between resource availability and insect spatio-temporal population dynamics.

 Researchers on the project:

Current:

Björn Eriksson (PhD student)

Mattias Larsson (Associate professor)

Collaborators:

Dr. Erik Hedenström (Professor, Mid-Sweden University)

Dr. Jocelyn Millar (Professor, University of California, Riverside, USA)

Dr. Nils Ryrholm, Gävle University College (Professor, University of Gävle)

Dr. Lars Westerberg (Associate professor, Linköping University)

PheroBio at Lund University

Alumni:

Dr. Mikael Molander (PhD student)

Dr. Inis Winde (Post-doc)

Dr. Joe Burman (Post-doc)

Dr. Franklin Nyabuga (Post-doc)

 Selected publications:

Thesis:

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