Biology subjects

Schlyter, F.

Publications and source records attributed to Schlyter, F..

3 recordsLinked to original sources

bioRxiv2024

Diet breadth in two polyphagous Spodoptera moths in a wide range of host and non-host plants and the potential for range expansion

O_LISeveral polyphagous moths are severe crop pests. Diet breadth patterns and mechanisms among polyphagous insects provide an excellent system to study ecological and evolutionary processes in herbivores, driving dietary specialization. However, studies of diet breadth on more than a handful of crops are scarce. C_LIO_LIHere, we estimated the diet breadth in two species of lepidopteran herbivores from the genus Spodoptera: S. littoralis (SL), with host range including both mono- and dicotyledonous plants and S. frugiperda (SF) Corn strain, primarily adapted to different grass species. C_LIO_LILarval performance on 23 crop and wild plant species from 17 families from terrestrial and wetland habitats was compared to an artificial diet in no-choice feeding bioassays. SL survived and performed better on most tested plants, particularly on the family level, except on two monocot plants (maize and leek), where SF performed well. There were five wild non-host plants where both generalists failed to survive. Nutrition indices assay corroborates the findings on a subset of plants. C_LIO_LIIn a subset of plants, larval feeding preference correlated partly, and larval attraction correlated well with larval performance. Female oviposition choice showed a weak correlation with larval performance. This weak correlation implies that these traits are decoupled, and other factors are crucial for female host plant selection. C_LIO_LIDuring larval dispersal greenhouse experiments, SL and SF larvae strongly tended to migrate onto their suitable host plants, indicating that this is one factor that modulates female host plant selection. C_LIO_LIIn summary, SL has a broader diet breath compared to SF, surviving on wild plants with no previous exposure. The present study provides the first comprehensive data on the diet breadth of two range-expanding and highly invasive polyphagous herbivores. C_LI

ecology↗

bioRxiv2023

Complex genomic landscape of inversion polymorphism in Europe's most destructive forest pest

In many species, polymorphic inversions underlie complex phenotypic polymorphisms and facilitate local adaptation in the face of gene flow. Multiple polymorphic inversions can co-occur in a genome, but the prevalence, evolutionary significance, and limits to complexity of genomic inversion landscapes remain poorly understood. Here, we examine genome-wide variation in one of Europes most destructive forest pests, the spruce bark beetle Ips typographus, scan for polymorphic inversions, and test whether inversions are involved in key adaptations in this species. We analyzed 240 individuals from 18 populations across the species European range and, using a whole-genome resequencing approach, identified 27 polymorphic inversions covering approximately 28% of the genome. The inversions vary in size and in levels of intra-inversion recombination, are highly polymorphic across the species range, and often overlap, forming a complex genomic architecture. We test several mechanisms, including directional selection, overdominance and associative overdominance that can contribute to the maintenance of inversion polymorphisms in the genome. We show that the heterogeneous inversion landscape is likely maintained by the combined action of several evolutionary forces and that inversions are enriched in odorant receptor genes encoding key elements of recognition pathways for host plants, mates, and symbiotic fungi. Our results indicate that the genome of this major forest pest of growing social, political, and economic importance harbors one of the most complex inversion landscapes described to date posing a question about limits of genomic architecture complexity.

evolutionary biology↗

bioRxiv2018

Using synthetic semiochemicals to train canines to detect bark beetle-infested trees

In this proof of concept study, we report the off season training of two detection dogs on a series of synthetic semiochemicals associated with Ips typographus pest bark beetle infestations of spruce trees. Scent detection training allowed dogs to discriminate between physiologically-relevant infestation (target) odours, quantified by GC-MS using extracted ion chromatogram to be bio-active at levels of < 10-4 ng /15 min or lower, and natural non-target odours that might be encountered in the forest. Detection dogs trained to recognize four different synthetic pheromone compounds in the winter time, well before beetle flight, were able to detect natural infested spruce trees unknown to humans the following summer. The trained detection dogs were able to detect an infested spruce tree from the first hour of bark beetle attack until several weeks after the attack. Trained detection dogs appear to be more efficient than humans in detecting early bark beetle infestations because the canines ability to cover a greater area and by olfaction detect infestations from a far greater distance than can humans. Infested spruce trees could be detected by trained detection dogs out to more than 100 m.\n\nKey MessageO_LIDetection dogs were rapidly trained to locate release of synthetic bark beetle pheromone components\nC_LIO_LISynthetics allowed dog training off-season both in laboratory and field\nC_LIO_LIDogs trained on synthetics detected naturally target pest insect attacked trees at a distance of more than 100 m.\nC_LIO_LIThe method allows rapid removal of single, first attacked trees before offspring emergence, thus curbing local pest increase and lowering spread of attacks in the landscap\nC_LI

ecology↗