Next generation biological control – an introduction
Hesran, Sophie Le; Ras, Erica ; Wajnberg, Eric ; Beukeboom, Leo W. - \ 2019
Entomologia Experimentalis et Applicata 167 (2019)7. - ISSN 0013-8703 - p. 579 - 583.
antagonistic micro-organisms - artificial selection - biocontrol - efficacy improvement - experimental evolution - genetic variation - induced plant resistance - molecular tools - natural enemies - parasitoids - pathogens - predators
Adaptation to developmental diet influences the response to selection on age at reproduction in the fruit fly
May, Christina M. ; Heuvel, Joost van den; Doroszuk, Agnieszka ; Hoedjes, Katja M. ; Flatt, Thomas ; Zwaan, Bas J. - \ 2019
Journal of Evolutionary Biology 32 (2019)5. - ISSN 1010-061X - p. 425 - 437.
ageing - experimental evolution - life-history evolution - phenotypic plasticity
Experimental evolution (EE) is a powerful tool for addressing how environmental factors influence life-history evolution. While in nature different selection pressures experienced across the lifespan shape life histories, EE studies typically apply selection pressures one at a time. Here, we assess the consequences of adaptation to three different developmental diets in combination with classical selection for early or late reproduction in the fruit fly Drosophila melanogaster. We find that the response to each selection pressure is similar to that observed when they are applied independently, but the overall magnitude of the response depends on the selection regime experienced in the other life stage. For example, adaptation to increased age at reproduction increased lifespan across all diets; however, the extent of the increase was dependent on the dietary selection regime. Similarly, adaptation to a lower calorie developmental diet led to faster development and decreased adult weight, but the magnitude of the response was dependent on the age-at-reproduction selection regime. Given that multiple selection pressures are prevalent in nature, our findings suggest that trade-offs should be considered not only among traits within an organism, but also among adaptive responses to different—sometimes conflicting—selection pressures, including across life stages.
Data from: Evolution of cross-resistance to medical triazoles in Aspergillus fumigatus through selection pressure of environmental fungicides
Zhang, J. ; Heuvel, Joost van den; Debets, A.J.M. ; Verweij, Paul E. ; Melchers, Willem J.G. ; Zwaan, B.J. ; Schoustra, S.E. - \ 2017
Wageningen University & Research
triazole resistance - cross-resistance - experimental evolution
Resistance to medical triazoles in Aspergillus fumigatus is an emerging problem for patients at risk of aspergillus diseases. There are currently two presumed routes for medical triazole-resistance selection: (i) through selection pressure of medical triazoles when treating patients and (ii) through selection pressure from non-medical sterol-biosynthesis-inhibiting (SI) triazole fungicides which are used in the environment. Previous studies have suggested that SI fungicides can induce cross-resistance to medical triazoles. Therefore, to assess the potential of selection of resistance to medical triazoles in the environment, we assessed cross-resistance to three medical triazoles in lineages of A. fumigatus from previous work where we applied an experimental evolution approach with one of five different SI fungicides to select for resistance. In our evolved lines we found widespread cross-resistance indicating that resistance to medical triazoles rapidly arises through selection pressure of SI fungicides. All evolved lineages showed similar evolutionary dynamics to SI fungicides and medical triazoles, which suggests that the mutations inducing resistance to both SI fungicides and medical triazoles are likely to be the same. Whole-genome sequencing revealed that a variety of mutations were putatively involved in the resistance mechanism, some of which are in known target genes.
Data from: Experimental evolution to increase the efficacy of the entomopathogenic fungus Beauveria bassiana against malaria mosquitoes: effects on mycelial growth and virulence
Valero Jimenez, C.A. ; Kan, J.A.L. van; Koenraadt, C.J.M. ; Zwaan, B.J. ; Schoustra, S.E. - \ 2016
experimental evolution - biocontrol - malaria
Entomopathogenic fungi such as Beauveria bassiana are currently considered as a potential control agent for malaria mosquitoes. The success of such strategies depends among others on the efficacy of the fungus to kill its hosts. As B. bassiana can use various resources for growth and reproduction, increasing the dependency on mosquitoes as a nutritional source may be instrumental for reaching this goal. Passage of entomopathogenic fungi through an insect host has been shown to increase its virulence. We evaluated the virulence, fungal outgrowth, mycelial growth rate, and sporulation rate of two B. bassiana isolates (Bb1520 and Bb8028) that underwent 10 consecutive selection cycles through malaria mosquitoes (Anopheles coluzzii) using an experimental evolution approach. This cycling resulted in an altered capacity of evolved B. Bassiana lineages to grow on different substrates while maintaining the ability to kill insects. Notably, however, there were no significant changes in virulence or speed of outgrowth when comparing the evolved lineages against their un-evolved ancestors. These results suggest that fungal growth and sporulation evolved through successive and exclusive use of an insect host as a nutritional resource. We discuss the results in the light of biocontrol and provide suggestions to increase fungal virulence.
Data from: Rapid multiple-level coevolution in experimental populations of yeast killer and non-killer strains
Pieczynska, M.D. ; Wloch-Salamon, D. ; Korona, R. ; Visser, J.A.G.M. de - \ 2016
Wageningen University & Research
killer yeast - dsRNA virus - experimental evolution - coeevolution
Coevolution between different biological entities is considered an important evolutionary mechanism at all levels of biological organization. Here we provide evidence for coevolution of a yeast killer strain (K) carrying cytoplasmic dsRNA viruses coding for anti-competitor toxins and an isogenic toxin-sensitive strain (S) during 500 generations of laboratory propagation. Signatures of coevolution developed at two levels. One of them was coadaptation of K and S. Killing ability of K first increased quickly and was followed by the rapid invasion of toxin-resistant mutants derived from S, after which killing ability declined. High killing ability was shown to be advantageous when sensitive cells were present but costly when they were absent. Toxin resistance evolved via a two-step process, involving the fitness-enhancing loss of one chromosome followed by selection of a recessive resistant mutation on the haploid chromosome. The other level of coevolution occurred between cell and killer virus. By swapping the killer viruses between ancestral and evolved strains, we could demonstrate that changes observed in both host and virus were beneficial only when combined, suggesting that they involved reciprocal changes. Together, our results show that the yeast killer system shows a remarkable potential for rapid multiple-level coevolution.
On the evolution of azole resistance in Aspergillus fumigatus
Zhang, J. - \ 2016
Wageningen University. Promotor(en): Bas Zwaan; P.E. Verweij, co-promotor(en): Fons Debets; Sijmen Schoustra. - Wageningen : Wageningen University - ISBN 9789462578555 - 183
aspergillus fumigatus - azoles - triazoles - aspergillosis - resistance - life cycle - asexual reproduction - sexual reproduction - experimental evolution - evolutionary genetics - agriculture - composting - medicine - aspergillus fumigatus - azolen - triazolen - aspergillose - weerstand - levenscyclus - ongeslachtelijke voortplanting - geslachtelijke voortplanting - experimentele evolutie - evolutionaire genetica - landbouw - compostering - geneeskunde
During the last decade azole resistance has increasingly been reported in Aspergillus fumigatus, which is a fungal pathogen involved in the vast majority of invasive aspergillosis infections in humans, and is now a global public health concern. Antifungal azoles, especially triazoles, are the drugs of choice for medical treatment. However, this treatment is hampered by the emergence of multi-azole resistant A. fumigatus isolates, especially the highly resistant variants TR34/L98H and TR46 /Y121F/T289A. Therefore, to control this disease, it is essential to elucidate by what mechanisms resistance emerges, how resistance spreads and how resistant genotypes persist in environments without azoles. The presented thesis shows the relevance of the life cycle of A. fumigatus to the development of azole resistance and possible evolutionary routes that lead to it. The work highlights the importance of fungal biology and evolution towards understanding the development of azole resistance in fungi. We conclude that azole resistance in A. fumigatus is a consequence of selection pressure by azole in the environment on the genetic variation generated via various aspects in the A. fumigatus life cycle. This thesis also introduces an experimental evolution approach to study the dynamics and mechanisms of the evolution of azole resistance. In addition, we investigate what condition can lead an environment to be a possible hotspot for the development of resistance. Finally, we link this to the potential conditions under which resistance can emerge and spread in the lungs of humans and how this depends on the specific azole used.
Overshooting dynamics in a model adaptive radiation
Meyer, J.R. ; Schoustra, S.E. ; LaChapelle, J. ; Kassen, R.K. - \ 2011
Proceedings of the Royal Society. B: Biological Sciences 278 (2011). - ISSN 0962-8452 - p. 392 - 398.
pseudomonas-fluorescens - experimental evolution - experimental populations - diversification - divergence - diversity - phenotype - history
The history of life is punctuated by repeated periods of unusually rapid evolutionary diversification called adaptive radiation. The dynamics of diversity during a radiation reflect an overshooting pattern with an initial phase of exponential-like increase followed by a slower decline. Much attention has been paid to the factors that drive the increase phase, but far less is known about the causes of the decline phase. Decreases in diversity are rarely associated with climatic changes or catastrophic events, suggesting that they may be an intrinsic consequence of diversification. We experimentally identify the factors responsible for losses in diversity during the later stages of the model adaptive radiation of the bacterium Pseudomonas fluorescens. Proximately, diversity declines because of the loss of biofilm-forming niche specialist morphotypes. We show that this loss occurs despite the presence of strong divergent selection late in the radiation and is associated with continued adaptation of resident niche specialists to both the biotic and abiotic environments. These results suggest that losses of diversity in the latter stages of an adaptive radiation may be a general consequence of diversification through competition and lends support to the idea that the conditions favouring the emergence of diversity are different from those that ensure its long-term maintenance
Natural variation in learning and memory dynamics studied by artificial selection on learning rate in parasitic wasps
Berg, M. van den; Duivenvoorde, L. ; Wang, G. ; Tribuhl, S.V. ; Bukovinszky, T. ; Vet, L.E.M. ; Dicke, M. ; Smid, H.M. - \ 2011
Animal Behaviour 81 (2011)1. - ISSN 0003-3472 - p. 325 - 333.
long-term-memory - consolidated memory - drosophila-melanogaster - experimental evolution - cotesia-glomerata - apis-mellifera - c-rubecula - honeybee - infochemicals - hymenoptera
Although the neural and genetic pathways underlying learning and memory formation seem strikingly similar among species of distant animal phyla, several more subtle inter- and intraspecific differences become evident from studies on model organisms. The true significance of such variation can only be understood when integrating this with information on the ecological relevance. Here, we argue that parasitoid wasps provide an excellent opportunity for multi-disciplinary studies that integrate ultimate and proximate approaches. These insects display interspecific variation in learning rate and memory dynamics that reflects natural variation in a daunting foraging task that largely determines their fitness: finding the inconspicuous hosts to which they will assign their offspring to develop. We review bioassays used for oviposition learning, the ecological factors that are considered to underlie the observed differences in learning rate and memory dynamics, and the opportunities for convergence of ecology and neuroscience that are offered by using parasitoid wasps as model species. We advocate that variation in learning and memory traits has evolved to suit an insect's lifestyle within its ecological niche
Evolutionary effects of fishing and implications for sustainable management: a case study of North Seas plaice and sole
Mollet, F.M. - \ 2010
Wageningen University. Promotor(en): Adriaan Rijnsdorp. - [S.l. : S.n. - ISBN 9789085856139 - 202
schol - tong (vis) - visserij - vis vangen - evolutie - rijpen - groei - voortplanting - levensgeschiedenis - kenmerken - adaptatie - visserijbeheer - duurzaamheid (sustainability) - zeevisserij - experimentele evolutie - plaice - dover soles - fisheries - fishing - evolution - maturation - growth - reproduction - life history - traits - adaptation - fishery management - sustainability - marine fisheries - experimental evolution
Exploited resources might genetically evolve as a consequence of ex¬ploitation by adapting their life history to the imposed mortality re¬gime. Although evolution favors traits for survival and reproduction of the fittest, human-induced evolution might have negative consequences for the exploiter. In general, a shift towards lower growth rate, earlier maturation and increased reproductive investment might be expected from increased (unselective) mortality and these changes might lead to generally smaller exploited individuals. Hence, the evolution might ne¬gatively affect the productivity of the resource and thus the sustainable exploitation and furthermore, genetic changes might be slow to reverse. If selection forces are high, evolution might occur fast and be observa¬ble within a few decades. Fisheries provide a large scale experiment for fisheries-induced evolution (FIE) since fishing mortality rates, typically being size-selective, exceed natural mortality rates by a multiple and data samples are available for decadal time scales. This thesis aims to assess the potential importance of FIE for sustainable exploitation by empirical evidence as well as evolutionary modeling, illustrated for the North Sea flatfish plaice and sole.
In empirical studies the problem of inferring on genetic changes from phenotypic observations lies in the disentangling of the phenotypic plasticity caused by environmental variations from the potential gene¬tic change. This is at least partly achieved by constructing norms of reaction that account for this environmental variation. The probabi¬listic maturation reaction norm for instance disentangles phenotypic plasticity in maturation caused by variation in growth. Because growth, maturation and reproductive investment are correlated due to tradeoffs on the individual level, a method was developed that fits an energy al¬location model to individual growth trajectories, obtained by the back-calculation of otoliths. This method provides size-specific estimates of the mechanistic individual life history tradeoffs and of the selection differentials imposed by the fishery. Because the correlation of esti¬mated life-history traits is captured, temporal changes could (for the first time) be analyzed conditionally on the correlation and on potenti¬al environmental effectors, thus disentangling not only environmental variability but also effects from changes in another trait. The results suggest that maturation shifted to occur earlier, surplus energy and reproductive investment increased partly due to environmental factors, but that all changes also bear a genetic component, indicative for FIE.
Species-specific individual-based eco-genetic models were developed to explore the evolutionary causes of reverse sexual size dimorphism in the case of flatfish. The hypothesis that males are smaller than fe¬males because of an energy loss through behavioural reproductive in¬vestments has to be rejected in this evolutionary perspective, since a higher demand on reproductive investment is compensated by increased energy acquisition. In contrast, the results show that males are smaller because increasing reproductive investment pays off less in males than in females. The finding can likely be generalized to many cases where mating opportunities are limited in space and time. Since eco-genetic models include the inheritance of traits with frequency-dependent se¬lection, they are therefore a powerful tool to study FIE and the model is therefore fitted to the estimated evolution of plaice and the evolu¬tionary impact of different management scenarios is assessed. The so called maximum sustainable yield MSY and the corresponding maximal fishing mortality FMSY evolve along with the population life history and occur both at lower levels after a while. The currently estimated refe¬rence points are thus not sustainable but slipping targets. By a dome-shaped exploitation pattern being protective for larger fish the evolu¬tionary trends could be reversed and with it the negative evolutionary impact. However, the evolutionary impact trades off against the short term loss in yield: by protecting the large fish the evolutionary impact is minimized but the instantaneous yield is decreased too – the optimal strategy for a given time horizon is somewhere in between. In summary, the thesis provides evidence that FIE should be taken into account for sustainable management.