IUFRO WP 7.03.16 & 7.03.05 – Seminar Series on “Behavioral and chemical ecology of bark and woodboring insects"

Following the launch of the IUFRO Working Party 7.03.16 in 2020, a webinar series was organized to promote the new working party and to highlight research focused on the behavioral and chemical ecology of forest insects. Following the success of that webinar series, the Working Parties 7.03.16 and 7.03.05 have collaborated to develop a webinar series on the “Behavioral and chemical ecology of bark and woodboring insects”. The webinar series is co-hosted by the Forestry and Agricultural Biotechnology Institute, University of Pretoria, the Institute for Forest Entomology, Forest Pathology and Forest Protection, BOKU, the Universidad de la Republica, Uruguay and the Canadian Forest Service.  This series consists of six webinars, each with a brief introduction to the subject and 2-3 research talks and will cover a wide range of topics related to the behavioral and chemical ecology of bark and woodboring insects. These virtual seminars are open to all registered participants.

Please fill in the registration form on the left menu of this page if you are interested in attending any of the seminars (please see the list of seminars, speakers and dates in the drop down menu on the left).  After registration you will be contacted by email with a link to attend the seminars. If you wish to contribute to future webinars series please contact the coordinators of this Working Party (Drs. Jeremy Allison, Sigrid Netherer and Andres Gonzalez).

 

All the talks are available for you to watch on Youtube.

 

PLEASE NOTE THAT THE SEMINAR START TIME IS 16:00 UTC

 

January 21 - Plant Defense and Biotic and Abiotic Stressors

Nadir Erbilgin, University of Alberta

16:00 - 16:15 Introduction by seminar leader

16:15 - 16:30 "Identifying anatomical and chemical defense fingerprints in Alberta lodgepole pine against mountain pine beetle" by Jennifer Klutsch, University of Alberta

16:30 - 16:45 "Presumed resistant: using current constitutive chemistry to predict historic resistance to insect outbreak" by Ken Keefover-Ring, University of Wisconsin-Madison

16:45 - 17:00 "Stress promotes access to alternate hosts for emerald ash borer" by Don Cipollini, Wright State University

17:00 - 17:30 Open discussion

 

February 04 - Visual Ecology of Forest Beetles

Johannes Spaethe, University of Wurzburg

16:00 - 16:15 Introduction by seminar leader

16:15 - 16:30 "Color and vision in Buprestidae: Blind to blue but with genetic work-arounds" by Nathan Lord, Louisiana State University

16:30 - 16:45 "Visual Responses of Male Agrilus spp. to Female Decoys Emitting Different Structural "Colors" and Light Strands" by Tom Baker, Pennsylvania State University

16:45 - 17:00 "Exploitation of the Visual Ecology of Woodboring Beetles for Survey and Detection" by Davide Rassati, University of Padova

17:00 - 17:30 Open discussion

 

February 18 – Finding a point source of odor in a turbulent world:  an overview of mechanisms and constraints

Ring Carde, University of California-Riverside

16:00 - 16:15 Introduction by seminar leader

16:15 - 16:30 "Gaseous Plumes in Forest Canopies: Concepts of Structure and Scale" by Harold Thistle, USDA Forest Service

16:30 - 16:45 "Using pheromone traps for surveillance of invasive moths: effects of ranging flight, distance of attraction, and efficiency of trap capture on detection" by Ring Carde, University of California-Riverside

16:45 - 17:00 "Beyond origami: Understanding mechanisms of differential trap performance to improve trap designs for forest Coleoptera" by Jeremy Allison, Natural resources Canada

17:00 - 17:30 Open discussion

 

March 04 - Climate Change Effects on Bark Beetle Range Expansion, Community Associates and Outbreak Dynamics

Barbara Bentz, USDA Forest Service, Rocky Mountain Research Station

16:00 - 16:15 Introduction by seminar leader

16:15 - 16:30 "Endemic niche requirements limit persistence potential of an eruptive herbivore in novel habitats: the fate of invasive mountain pine beetle in the western boreal forest." by Allan Carroll, University of British Columbia

16:30 - 16:45 "Comparing communities of the “not-so-Southern pine beetle” (Dendroctonus frontalis) between its historical and advancing northern range" by Jeff Garnas, University of New Hampshire

16:45 - 17:00 "Effects of climate on ectosymbiotic community dynamics associated with bark and ambrosia beetles" by Richard Hofstetter, Northern Arizona University

17:00 - 17:30 Open discussion

 

March 18 - Behavioural and Invasion Ecology of Hylurgus ligniperda

Ecki Brockerhoff, Swiss Federal Research Institute WSL

16:00 - 16:15 Introduction by seminar leader

16:15 - 16:30 "Dispersal of H. ligniperda: Evidence from release-recapture experiments" by Nicolas Meurisse, Scion

16:30 - 16:45 "Allee effects in invasions of H. ligniperda" by Kevin Chase, Bartlett Tree Research Laboratory

16:45 - 17:00 "Population genetic evidence of invasion routes of H. ligniperda" by Lea Bischofberger, ETH Zurich.

17:00 - 17:30 Open discussion

 

April 01 -Chemical Ecology of Ips typographus – Norway spruce Interactions

Sigrid Netherer, University of Vienna

16:00 - 16:10 Introduction by seminar leader

16:10 - 16:35 "Norway spruce vulnerability for bark beetle attack under abiotic stress conditions" by Anna Jirosová, Czech University of Life Sciences

16:35 - 17:00 "Does bark beetle attack history change the induction of terpene and phenolic defenses in mature Norway spruce?" by Raimund Nagel, University of Leipzig

17:00 - 17:30 Open discussion

Registration information

Please fill in the registration form below if you are interested in attending any of the seminars in this series. After registration you will receive a confirmation email with a link to attend the seminars. Please also check your junk mail folder. If you do not receive a confirmation email, please notify Quentin Guignard at quentin.guignard@fabi.up.ac.za.

 

 

REGISTRATION IS NOW CLOSED

2021 Seminars, speakers and dates (Jan-Feb)

Seminars for January 21, 2021

Introduction and opening seminar

Speaker: Nadir Erbilgin, University of Alberta, Canada

 

Abstract: Climate change has a strong influence on expression and responses of plant primary and secondary metabolites. Investigating such plant responses has become more critical as the North American forests have been frequently invaded by invasive insect herbivores. Studies have either primarily focused on the effects of climate change on the biology and ecology of invading insects or how climate change affects host plant quality (suitability and susceptibility) to the invaders. In this webinar the three presenters will bring your attention on three such invasive insect herbivores: emerald ash borer, spruce beetle, and mountain pine beetle in invading ash, spruce and pine forests in North America respectively.

 

 

 

Title: Identifying anatomical and chemical defense fingerprints in Alberta lodgepole pine against mountain pine beetle.

Speaker: Jennifer Klutsch, University of Alberta, Canada

 

Abstract: Anatomical and chemical defenses of trees can be important biomarkers for resistance to insects. The recent expansion of mountain pine beetle (Dendroctonus ponderosae) into lodgepole pine (Pinus contorta var. latifolia) forests of Alberta has raised the need to identify natural resistance in this naïve population. We characterized lodgepole pine defenses in both pre- and post-outbreak stands. Trees having larger but fewer resin ducts showed higher survival probability compared to those with smaller but more abundant resin ducts annually. We also determined host suitability to mountain pine beetle based on chemical profiles and found that the concentration and proportion of important monoterpenes were predictors of mountain pine beetle performance. Screening for these anatomical and chemical defense traits may be a tool for identifying trees with important resistance factors against mountain pine beetle.

 

 

 

Title: Presumed resistant: using current constitutive chemistry to predict historic resistance to insect outbreak.

Speaker: Ken Keefover-Ring, University of Wisconsin-Madison, USA

 

Abstract: The spruce beetle (Dendroctonus rufipennis) is responsible for the death of more North American spruce trees than any other biotic agent. While Engelmann spruce is the main host in the lower 48 U.S. states, white spruce (Picea glauca) is the preferred host in the beetle’s northern range, including Alaska. Conifers defend themselves from bark beetles with both constitutive and induced levels of oleoresin, which consists mostly of a mixture of lower molecular weight volatile mono- (C10) and sesquiterpenes (C15) and larger non-volatile diterpenes (C20). Due to the compound toxicity and relatively high viscosity, tree oleoresin constitutes both a chemical and physical defense. The object of this study was to determine the role of constitutive phloem terpenoid chemistry of white spruce in resistance against spruce beetle. We took advantage of a plantation of white spruce on the Kenai Peninsula consisting of trees grown from seeds collected from different locations prior to the largest outbreak of spruce beetle in Alaska’s history (1980-89, BEFORE) and seeds from the same locations from surviving trees (1998, AFTER, presumed resistant trees). We collected phloem samples from 270 trees, evenly divided between BEFORE and AFTER trees, and measured tree DBH, phloem thickness, and terpenoid chemistry. Our main goal was to determine whether patterns of inherited constitutive chemistry can predict resistance to beetle attack.

 

 

 

Title: Stress promotes access to alternate hosts for emerald ash borer.

Speaker: Don Cipollini, Wright State University, USA

 

Abstract: Emerald ash borer, Agrilus planipennis, an Asian specialist wood borer, has killed hundreds of millions of ash trees in North America and elsewhere. In its ancestral range, it is primarily a secondary pest, only attacking and severely damaging already stressed hosts. In North America, however, it can attack and eventually kill healthy ash hosts, but biotic and abiotic stress can affect attack rates and the degree of resistance and tolerance displayed by individual trees. Emerald ash borer is also capable of completing development on two non-ash hosts, white fringetree, Chionanthus virginicus, and cultivated olive, Olea europaea. Like in their ancestral hosts, stress typically increases the susceptibility of these hosts to emerald ash borer, which show moderate to high resistance when healthy. Changes in resistance due to stress may be linked to changes in physical or nutritional characteristics of phloem tissue, or due to alterations in secondary metabolite concentrations, but the causes are not always clear. Overall, abiotic and biotic stresses allow emerald ash borer to expand its typically narrow host range, which may become of increasing concern with multiple interacting stresses in nature.

 

 

 

Seminars for February 04, 2021

Introduction and opening seminar

Speaker: Johannes Spaethe, University of Wurzburg, Germany

 

Abstract: Vision is a key sensory modality for most beetles (Coleoptera), which form the largest insect order with more than 350,000 described species. Within the order, a large variety of eye types (e.g. apposition and superposition design), eye sizes (from a few dozens to several thousand ommatidia per eye) and photoreceptor numbers (between one and four) occurs, which correlates to the specific behavior and ecological needs of the possessors. I will present a brief overview of beetle eye designs and the related consequences and limitations for spatial and color vision.

 

 

 

Title: Color and vision in Buprestidae: Blind to blue but with genetic work-arounds

Speaker: Nathan Lord, Louisiana State University, USA

 

Abstract: The economically important beetle family Buprestidae, commonly known as the metallic woodboring beetles or jewel beetles, are the 8th most speciose group of Coleoptera. Whereas most insects are shades of brown, the jewel beetles are an exception—most are colorful, with colors and patterns resulting from both structural and pigmentary mechanisms. With reference to visual systems, insects are predominantly trichromats, with sensitivities in the UV, short-wave (blue) and long-wave (green) regions of the electromagnetic spectrum. Here we present studies that demonstrate the loss of short-wave sensitivity in jewel beetles, the genetic mechanisms for mitigating this loss, and the potential role in color and pattern in this visually mediated group.

 

 

 

Title: Visual Responses of Male Agrilus spp. to Female Decoys
Emitting Different Structural “Colors" and Light-Strands.

Speaker: Tom Baker, Pennsylvania State University, USA

 

Abstract: Males of all five Agrilus spp. that we have investigated over the years in N. America and Europe respond visually, not via odor, to females perched on leaves in bright sunlight.  Males hover in flight over the female and drop down to land either directly on the female or immediately beside it. Females emit species-specific wavelengths of light, i.e., “structural colors” from their elytral cuticle that make them appear to humans to be differentially colored, with different species appearing relatively blue, green, orange, or red. The Agrilus spp.  that we worked with also encompass a large range of sizes, from the very small (e.g., Agrilus angustulus and A. cyanescens) to the largest (e.g., A. planipennis, A. biguttatus). Our field research, which largely employed visual models pinned to leaves — i.e., “visual decoys” — to evoke male landing responses revealed that males respond fairly species-specifically to their female models, but there is a large amount of interspecific visual cross-attraction. Much of the specificity appears to be due to size of females and males of a species, and so the contribution of species-specific dominant wavelengths of light to conspecific attraction remains unclear. The presence of refracted strands of light from elytral spicules in A. planipennis has been implicated in promoting male attraction to, in-flight hovering over, and landing on females.

 

 

 

Title: Exploitation of the Visual Ecology of Woodboring Beetles for Survey and Detection.

Speaker: Davide Rassati, University of Padova, Italy

 

Abstract: Traps baited with attractive blends are used at ports of entry worldwide to intercept longhorn beetles accidentally introduced via international trade. These trapping programs have so far relied almost exclusively on black traps but no study thoroughly tested whether colored traps perform better than black traps in detecting longhorn beetles. We showed that trap color can strongly increase attractiveness of longhorn beetles to baited traps, especially when targeting flower-visiting species, and that surveillance programs must include colored traps along with commonly used black traps to improve the likelihood of detecting longhorn beetles potentially moved with trades.

 

 

 

Seminars for February 18, 2021

Introduction and opening seminar

Speaker: Ring Carde, University of California-Riverside, USA

 

Abstract: The distribution of odor in a windborne odor plume is governed by the forces of turbulence (molecular diffusion is too slow a process to influence plume structure). As the plum e is carried downwind, it is fragmented into odor filaments, some of which can retain high concentrations of odor for 10s of meters, and odor gaps. Flying insects orient along such plumes by optomotor anemotaxis—heading upwind using feedback from their visual surround to gauge their heading. This webinar will provide an overview of how odor plumes move in forest settings and some consequences of odor plume dynamics for surveillance of forest insects.

 

 

 

Title: Gaseous Plumes in Forest Canopies: Concepts of Structure and Scale.

Speaker: Harold Thistle, USDA Forest Service.

 

Abstract: In detail, the air flow through a forest canopy is extremely complex.  Multiple, often flexible, non-uniformly distributed surfaces combine with differential heating and the inherently stochastic nature of turbulent flow to yield a very challenging problem.  The nature of the problem makes it difficult to explicitly predict the speed and direction of in-canopy air flow in space and time.  This fact then bears on the understanding of the movement of a gaseous plume released into this complex flow.  However, decades of work on this problem from the standpoint of fundamental fluid dynamics, micrometeorology and air pollution engineering (among many other fields) has resulted in a working understanding of in-canopy air flow and gaseous dispersion in plant canopies.


This talk focuses on chemical signaling by insects living in or near a plant canopy.  Concepts such as Strouhal Number, Nyquist frequency and the turbulent energy cascade are presented in a fairly qualitative manner and used to understand the interaction of the sources of the gas (insects, traps, lures etc.) with the surrounding atmosphere.  Large field studies conducted in forest canopies using tracer gasses and focused on investigating chemical signaling will be used to substantiate points.  The role of canopy density and canopy element size will be discussed.  Further, coupling between the in-canopy and above canopy atmosphere and the often critical role of vertical temperature structure in dispersion dynamics will be presented.

 

 

 

Title: Using pheromone traps for surveillance of invasive moths: effects of ranging flight, distance of attraction, and efficiency of trap capture on detection.

Speaker: Ring Carde, University of California-Riverside.

 

Abstract: Pheromone-baited traps are widely used to signal the presence of pest moths—indeed, >1,000 moth species have useful attractive lures. One of more important applications is in surveillance for invasive species and if they become established, to delimit their distribution. For example, typically >200,000 traps are deployed yearly in the United States for detection of the Asian strain of the gypsy moth (especially along the west coast) and to establish where in the eastern half of the U.S. the established European populations are low enough along their leading invasive edge to be controlled by mating disruption (the “slow-the-spread- program”). The major concern in such efforts is false negatives: not detecting a low-level population. Using simulations and mark-release-recapture, we can suggest the likelihood pf missing an incipient population, given assumptions of moths available, trap density, and the capture efficiency of the trap.

 

 

 

Title: Beyond origami: Understanding mechanisms of differential trap performance to improve trap designs for forest Coleoptera.

Speaker: Jeremy Allison, Natural resources Canada

 

Abstract: Intercept traps baited with pheromone and host attractants are commonly used in monitoring programs for non-native species, to delimit quarantine and treatment zones, to survey population levels to determine if and where interventions are needed, and to evaluate the impact of management efforts. The optimal trap design has been reported to vary among taxa and studies. We conducted a meta-analysis of the trapping literature for forest Coleoptera and observed that overall panel traps captured more individuals than multiple-funnel traps regardless of guild or family. A significant amount of heterogeneity in the effect of trap type was observed that was only partially explained by variation among guilds and families. The visual stimuli presented by and structure of odorant plumes emanating downwind are two putative mechanisms for the differences in performance of different intercept trap designs. We conducted field trapping experiments and analyses of plume structure in a greenhouse which provide some support for both mechanisms.

 

 

 

2021 Seminars, speakers and dates (Mar-Apr)

Seminars for March 04, 2021

Introduction and opening seminar

Speaker: Barbara Bentz, USDA Forest Service, Rocky Mountain Research Station, USA

 

Abstract: Dendroctonus bark beetle physiological processes, as with all insects, are dependent on their environment. Temperature directly effects bark beetles through 1) development and growth rates, 2) the induction, development and termination of diapause, and 3) mortality from extreme temperatures. These traits are targets of selection in seasonal environments and have evolved in historical climate regimes. The geographic ranges of many Dendroctonus species extend across pronounced latitudinal and elevational thermal gradients, and clinal variability in these important traits have been observed. Because of the complex and integrated traits involved, predicting future population success will require an understanding of the evolved timing and thermal sensitivity of multiple traits. A review of the knowledge of development rates, diapause and cold hardening in two species native to North America, Dendroctonus ponderosae (mountain pine beetle) and D. rufipennis (spruce beetle), will be presented focusing on the potential influence of changing temperatures on these traits and ultimately population survival and success in a future climate.

 

 

 

Title: Endemic niche requirements limit persistence potential of an eruptive herbivore in novel habitats: the fate of invasive mountain pine beetle in the western boreal forest.

Speaker: Allan Carroll, University of British Columbia, Canada

 

Abstract: Climate warming has been implicated in recent hyperepidemics by eruptive species capable of altering ecosystem processes in habitats outside their historic range.  However, range expansion during epidemics may not result in long-term persistence in novel habitats if sub-outbreak (endemic) populations require niche conditions that are distinct from epidemic populations.  Mountain pine beetle (Dendroctonus ponderosae), the most severe disturbance agent within the lodgepole pine (Pinus contorta var. latifolia) forests of western North America, recently breached the historic geoclimatic barrier of the Rocky Mountains and expanded its range into evolutionarily naïve lodgepole pine and jack pine (Pinus banksiana) habitats contiguous with the transcontinental boreal forest.  In this study, we examined the potential for mountain pine beetles to naturalize in newly invaded pine habitats by quantifying biotic interactions known to affect endemic population dynamics (i.e., the endemic niche) in 16 pine stands along a transect from the native range to the eastern edge of the invasion front.  We found that there was 3 times the density (trees/ha) of endemic-susceptible hosts (vigour-impaired trees as indicated by the presence of secondary bark beetle species) in native and naïve lodgepole pine habitats when compared with jack pine.  The degree of inter-tree competition within a stand, which was generally low in jack pine, was found to be positively correlated with endemic-susceptible host abundance, and to be negatively correlated with tree size and growth rate.  Additionally, subcortical competitor assemblages shifted from predominantly secondary bark beetles (Coleoptera: Curculionindae: Scolytinae) in the native range to woodboring beetles (Coleoptera: Cerambycidae) in jack pine.  In newly invaded jack pine forests, 50% of endemic-susceptible trees were co-occupied by woodboring beetle species (Tetropium and Monochamus spp), whereas this was rare in native (ca. 0%) and naïve (20%) lodgepole pine forests.  In the native range, trees susceptible to endemic mountain pine beetles that were also infested by woodborers exhibited slightly higher (ca. 25%) phloem consumption than trees infested by bark beetles alone, but phloem consumption by woodborers in trees in newly invaded lodgepole and jack pine habitats was 6 and 17 times greater, respectively, than that associated with bark beetles only.  Thus, the endemic niche in novel habitats, especially jack pine, was further constrained by greater exploitation and interference competition.  Novel lodgepole pine habitats comprise equal, if not greater suitability to endemic populations; however, the niche available to endemic mountain pine beetle in jack pine forests appears to be rare and highly constrained by competitors suggesting that long-term persistence in western boreal jack pine is unlikely.

 

 

 

Title: Comparing communities of the “not-so-Southern pine beetle” (Dendroctonus frontalis) between its historical and advancing northern range

Speaker: Jeff Garnas, University of New Hampshire, USA

 

Abstract: Climate-driven range shifts are an increasingly common phenomenon among many taxa, including insects. Understanding how populations respond to potential changes in associated community diversity and composition is a key to predicting impacts. For example, range shifting species that leave key competitors or natural enemies behind have the potential to increase in aggressiveness. Alternatively, reduced abundance or diversity among facultative mutualists within advancing range edges could mitigate impacts. Additionally, novel interactions within naïve communities have the potential to alter management outcomes and/or could have spillover effects on linked communities. Here we compare a long-term dataset of Southern pine beetle (SPB) gallery associates from the core of the species’ historical range with contemporary sites in the range-expanding north (Long Island, NY). Surprisingly, rarefied arthropod richness was marginally higher in novel northern sites when pooling across sampling methods. The ecologically important clerid beetle predator, Thanasimus dubius Fabricius, was present in approximately equal densities across regions. Fly and wasp natural enemies and Ips engraver beetle richness was also similar between regions, but abundances were substantially lower in northern sites. Likewise, incidence and abundance of Ips avulsus – a dominant, widespread interactor in southern sites – were considerably lower in Long Island. Reduced competition with Ips, particularly I. avulsus in the tops of attacked trees, could in part explain higher proportional bole utilization by SPB as observed in NY sites. Despite these differences, SPB gallery communities are compositionally similar across sites in the south versus the novel northern range. The existence of robust and diverse communities along the advancing edge do not suggest significant enemy release. Ongoing research on community interactions as they relate to SPB dynamics in the North will add to core understanding of key feedbacks and their implications for management.

 

 

 

Title: Effects of climate on ectosymbiotic community dynamics associated with bark and ambrosia beetles.

Speaker: Richard Hofstetter, Northern Arizona University, USA

 

Abstract: Climate-driven range shifts are an increasingly common phenomenon among many taxa, including insects. Understanding how populations respond to potential changes in associated community diversity and composition is a key to predicting impacts. For example, range shifting species that leave key competitors or natural enemies behind have the potential to increase in aggressiveness. Alternatively, reduced abundance or diversity among facultative mutualists within advancing range edges could mitigate impacts. Additionally, novel interactions within naïve communities have the potential to alter management outcomes and/or could have spillover effects on linked communities. Here we compare a long-term dataset of Southern pine beetle (SPB) gallery associates from the core of the species’ historical range with contemporary sites in the range-expanding north (Long Island, NY). Surprisingly, rarefied arthropod richness was marginally higher in novel northern sites when pooling across sampling methods. The ecologically important clerid beetle predator, Thanasimus dubius Fabricius, was present in approximately equal densities across regions. Fly and wasp natural enemies and Ips engraver beetle richness was also similar between regions, but abundances were substantially lower in northern sites. Likewise, incidence and abundance of Ips avulsus – a dominant, widespread interactor in southern sites – were considerably lower in Long Island. Reduced competition with Ips, particularly I. avulsus in the tops of attacked trees, could in part explain higher proportional bole utilization by SPB as observed in NY sites. Despite these differences, SPB gallery communities are compositionally similar across sites in the south versus the novel northern range. The existence of robust and diverse communities along the advancing edge do not suggest significant enemy release. Ongoing research on community interactions as they relate to SPB dynamics in the North will add to core understanding of key feedbacks and their implications for management.

 

 

 

Seminars for March 18, 2021

Introduction and opening seminar

Speaker: Ecki Brockerhoff, Swiss Federal Research Institute WSL, Switzerland

 

Abstract: 

Hylurgus ligniperda, the red-haired or golden-haired pine bark beetle is probably the most successful invasive bark beetle. It is native to Europe and northern Asia but has invaded at least seven regions or countries independently, to our knowledge more than any other true bark beetle. In its native region, it has been somewhat neglected and received little attention from scientists, mainly because it is not considered a forest pest. Hylurgus ligniperda breeds in stems and roots in ground contact or near the ground of recently dead pines. The widespread use of wood packaging materials (pallets, etc.) in international trade is thought to be responsible for the spread of this species to many non-native regions.

Establishment in these regions has been facilitated by the large-scale cultivation of exotic pine plantations, especially in the southern hemisphere, which has provided a very large resource of breeding material with little competition from other species. This resulted in the development of huge populations of H. ligniperda, which are probably responsible for further spread to other regions. Although H. ligniperda does not damage living trees, it is considered a quarantine pest and, therefore, measures are taken to reduce its presence on logs destined for export. Consequently, much research on phytosanitary treatments against H. ligniperda has been undertaken in several southern hemisphere countries. But due to its successful invasion and considerable abundance in many countries, it has also received some attention in behavioural and ecological research, and it has been used as a ‘model invader’. Examples from these studies will be given in this introduction, followed by more detailed presentations focused on (i) invasion experiments examining the role of propagule pressure and Allee effects, (ii) population genetics analyses to unravel its invasion history, and (iii) release-recapture studies of dispersal.

 

 

 

Title: Dispersal of H. ligniperda: Evidence from release-recapture experiments.

Speaker: Nicolas Meurisse, Scion, New Zealand

 

Abstract: 

As one of the most successful invasive bark beetles worldwide, Hylurgus ligniperda is now commonly found throughout most major Pinus growing regions. Adult beetles are active flyers and efficient colonisers of recently dead or dying trees. In this seminar, I will present the results of a mark-recapture experiment that examined adult dispersal patterns of H. ligniperda in a clearcut Pinus radiata plantation forest in New Zealand. Within forest dispersal is recognized as a key trait influencing the distribution and local abundance of the species, hence its probability of colonisation of recently harvested pine logs. I will discuss our results with regards to H. ligniperda host exploitation and dispersal mechanisms, as well as in a context of proactive management of the phytosanitary risk associated with export logs. For instance, we will consider how landscape knowledge of potential source populations can be combined with dispersal knowledge to estimate pest pressure at sensitive areas such as harvest and timber storage sites. Although dispersal has been studied for a range of aggressive `tree killing' bark beetles, very little research has considered the dispersal behaviour of non-aggressive saprophytic bark beetles such as H. ligniperda that only utilize kairomones (host volatiles) but no pheromones (to our knowledge). Further development of robust and quantitative predictions for forest insect dispersal also prove useful to inform risk assessments, not only for H. ligniperda but similarly for other species that have a demonstrated ability to be invasive.

 

 

 

Title: Allee effects in invasions of H. ligniperda.

Speaker: Kevin Chase, Bartlett Tree Research Laboratory, USA

 

Abstract: A crucial factor affecting the colonization process of invading species is propagule pressure, the size and frequency of arriving populations. A key determinant contributing to propagule pressure effects on invasion success is the ‘Allee effect’, which is defined as increasing population growth with increasing abundance. We conducted parallel experimental releases using two species of bark beetles, Hylurgus ligniperda in New Zealand and Ips pini in North America, to (i) quantify colonization thresholds, (ii) empirically test for Allee effects, and (iii) assess the role propagule pressure in invasion success. Establishment success was positively associated with release density (i.e., propagule pressure) for both species but colonization success generally occurred at lower densities for H. ligniperda than for I. pini. We discuss the biological characteristics determining colonization success. Our results linking invasion failure to small founding population sizes generally support the theoretical literature on the role of propagule pressure and Allee effects in biological invasions.

 

 

 

Title: Population genetic evidence of invasion routes of H. ligniperda.

Speaker: Lea Bischofberger, ETH Zurich, Switzerland

 

Abstract:

Pines (Pinus spp.) are widely planted in non-native ranges mainly for timber production. These pine plantations have facilitated the establishment of invasive insects in the non-native range of their host plants. One of the most successful invasive bark beetles (Scolytinae) is Hylurgus ligniperda, also known as the red-haired or golden-haired pine bark beetle, which is native to Europe and adjacent regions. Hylurgus ligniperda has become established in most continents including Australasia, Africa, South and North America. In its non-native range, H. ligniperda benefits from large amounts of breeding material (i.e., woody debris in pine plantations), so that it is often very abundant. The literature describes possible spread of H. ligniperda to new regions from previously invaded regions (the so-called bridgehead effect) and not directly from native populations. For a better understanding of the likely invasion routes of H. ligniperda, a population genetic approach was chosen to compare individuals from native and non-native populations.  

Hylurgus ligniperda samples were trapped in several countries in both native and non-native regions. In Europe samples originated from countries where the species is known to naturally occur in the wild, namely France (1 sampling area), Greece (1), Hungary (2), Italy (3), and Portugal (4). Samples from the non-native area were from Argentina (2 sampling areas), Chile (3), New Zealand (2), Portugal (4), South Africa (2), Uruguay (2), and United Sates of America (5). For genetic analyses, both a mitochondrial marker (Cytochrome oxidase I, COI) and a nuclear marker (Arrestin 2, Arr2) were used. For COI, 257 samples and for Arr2 233 samples were analysed. Identical sequences were grouped together in SplitsTree. A haplotype network analysis and a discriminant analysis of principal components were performed in R. The results from these analyses indicate which populations are more closely related and, thus, more likely to have served as sources of non-native populations. Our findings will give us a better understanding of pathways of spread, introductions, and bridge-head effects of the invasive species H. ligniperda.

 

 

 

Seminars for April 01, 2021

Introduction and opening seminar

Speaker: Sigrid Netherer, Institute of Forest Entomology, Forest Pathology and Forest Protection, Department of Forest and Soil Sciences, University of Natural Resources and Life Sciences, Vienna (BOKU)

 

Abstract: This seminar reports on three comprehensive field studies investigating various aspects of Norway spruce susceptibility to attacks by the Eurasian spruce bark beetle, Ips typographus in view of global warming. The Rosalia Roof Study at BOKU, Austria, is focused on the effects of drought on bark beetle host acceptance and Norway spruce defence. Similarly, field experiments in the frame of the EXTEMIT-k project at CULS in Czech Republic are aimed to elucidate the influence of climatic stress of trees at freshly cut forest edges on concentrations and emissions of bark defence compounds. Overall bark contents of terpenoid compounds and of particular phenolic substances are increased in response to inoculation of ophiostomatoid fungi associated with the spruce bark beetle. Bark beetle attack history plays an important role in tree resistance to fungal invasion as observed at study trees in outbreak areas of the Austrian Limestone Alps and the Bohemian Forest at the border between Austria and Czech Republic.

 

 

 

Title:Norway spruce vulnerability for bark beetle attack under abiotic stress conditions.

Speaker: Anna Jirosová, Czech University of Life Sciences, Faculty of Forest and Wood Sciences, Prague, Czech Republic

 

Abstract:

Forests of the Czech Republic have experienced devastating damages of Norway spruce monocultures caused by bark beetle mass outbreaks in the recent years. Total volumes of trees killed mainly by the Eurasian spruce bark beetle exponentially increased from 1.5 million m3 timber annually in 2003-2015 to 23 million m3 timber in 2019. In response to these ongoing calamities, a multidisciplinary research group was established at our faculty at CULS in Prague, with the aim to advance knowledge on I. typographus ecology and damage mitigation.

The chemical ecology team within this research group focuses on Ips typographus-Norway spruce interactions with regard to beetle host selection. We ask why certain spruce trees in the forest are more susceptible to bark beetle attack, and how external stressors, such as drought, solar radiation and rising temperatures affect defence ability. In a comprehensive field study, stress levels of trees were manipulated by the cutting of fresh forest edges leading to sudden sun exposure in spring. Monitoring of trees included physiological features such as sap and resin flow, and secondary metabolites profile in the bark for tree defence. These records were related to bark beetle attacks as observed in field bioassays, showing differences between trees at the fresh forest edge and in the forest interior.

Another aspect of our studies is the biological activity of compounds in the Norway spruce/Ips typographus/associated ophiostomatoid fungi system, such as oxygenated monoterpenes in tree bark and compounds emitted by exo-symbiotic fungi. We are interested in which particular compounds and mixtures of compounds show attractive or repellent effects on bark beetles and might be promising candidates for usage in applied bark beetle management.

 

 

 

Title: Does bark beetle attack history change the induction of terpene and phenolic defenses in mature Norway spruce?

Speaker: Raimund Nagel, Institute for Biology, Faculty of Life Sciences, Universität Leipzig, Germany

 

Abstract: Terpene and phenolic compounds are important conifer defences against bark beetles and their associated fungi. Mature Norway spruce (Picea abies) trees, with and without documented histories of attack by the spruce bark beetle, Ips typographus, were inoculated with the blue-stain fungus Endoconidiophora polonica. We measured the concentration of terpenes and phenolics in the bark before and 14 days after fungal inoculation and the expression of genes encoding key enzymes in their biosynthesis. In addition, intermediates of the terpene biosynthetic pathway and levels of defensive hormones in the same tissue were quantified. The overall terpene concentration increased significantly, while in case of the phenolics only two increased significantly. Transcript levels of genes involved in both pathways were significantly higher after inoculation. A similar pattern was found for enzymatic activity of isoprenyl diphosphate synthases and the concentration of their prenyl diphosphate products in inoculated trees. Quantification of phytohormones revealed the significant induction of the jasmonate pathway, but not the salicylic acid pathway after fungal inoculation. Our data highlight the coordinated induction of terpenes and phenolics in spruce upon attack by E. polonica, the fungal associate of I. typographus. 

 

 

2020 Seminar series

 

The seminar series is now done and all the talks are available for you to watch on Youtube.

 

Seminars for September 17, 2020

Introduction and opening seminar

Speaker: Dr. Bill Hansson, Max Planck Institute for Chemical Ecology, Jena, Germany

 

Abstract: All insects, with few exceptions, depend heavily on olfactory input to survive and reproduce. In this mini symposium we will put the spotlight on a couple of examples, where forest insects and their sense of smell are being investigated. In my short introduction I will provide a brief background to the insect sense of smell in general, mainly based on our present research on fruit flies and moths, and then proceed with a quick look at some of my own scarce projects on forest insects.

 

Biography: BSc and PhD in Ecology at Lund University 1979-1988. Postdoc at the University of Arizona 1989-1990. Career in Lund until Full Professor 2001. Recruited as Professor, Head of Department and Vice Dean at the Swedish University of Agricultural Sciences (SLU) in Alnarp in 2001. Called to a Max Planck Directorship at the Max Planck Institute for Chemical Ecology in Jena in 2006. Served as Vice President of the Max Planck Society 2014-2020. Full CV.

 

 

Title: Functional characterization of two bark beetle (Ips typographus) pheromone receptors and prediction of their ligand binding sites

Speaker: Dr. Martin N. Andersson, Department of Biology, Lund University, Lund, Sweden

 

Abstract: Improved management of the destructive Eurasian spruce bark beetle Ips typographus (‘Ityp’) is urgently needed, and one avenue forward could be to target the odorant receptors (ORs), which are used by the beetles to find mates and host trees. We characterized the function of two ItypORs, showing selective responses to the  pheromone compounds (S)-(-)-ipsenol and (R)-(-)-ipsdienol, respectively. We also predicted the ligand binding sites of these ORs, and the importance of two residues in pheromone binding was experimentally supported. Apart from reporting the first bark beetle ORs with determined functions, our findings may represent an important step towards improved control of bark beetles. For instance, these ORs can now be screened for better agonists or antagonists, or employed in biosensors for detection of bark beetle infestations.

 

Biography: PhD from the Swedish University of Agricultural Sciences in 2011. Since 2017 Associate Professor at Lund University, Sweden, with main research interests including olfaction in bark and ambrosia beetles with special emphasis on the evolution and function of odorant receptors. Since 2019 also Principal Investigator in the Max Planck Centre next-Generation Insect Chemical Ecology (nGICE).

 

 

Title: Olfactory genomics as a tool to expedite pheromone identification in longhorned beetles

Speaker: Dr. Robert Mitchell, University of Wisconsin Oshkosh, USA 

 

Abstract: The family of longhorned beetles (Coleoptera: Cerambycidae) includes many wood-boring pests of international significance for which attractive pheromones can be a useful tool in monitoring and control. Members of the family produce several pheromone structures that are conserved across genera, tribes, and subfamilies, resulting in many clusters of species that are attracted to identical pheromone components. Each pheromone is detected by a corresponding chemoreceptor expressed in the antennae, but it remains unclear if the chemoreceptor genes have remained as conserved as the pheromones. In this talk, I will discuss recent progress on the pheromone biology of longhorned beetles, their chemoreceptors, and the possibility of using conserved chemoreceptor sequences to infer the pheromone chemistry of unstudied species.

 

Biography: Assistant Professor at the University of Wisconsin Oshkosh studying the chemical ecology of insects, especially the order Coleoptera. Recent laboratory research has emphasized olfactory biology of the Cerambycidae and the evolution of chemoreceptors across beetle families.

 

 

Seminars for October 1, 2020

Title: Evolutionary ecology of insect-fungus mutualisms

Speaker: Dr. Peter H.W. Biedermann, Chair of Forest Entomology and Protection, University of Freiburg, Germany

 

Abstract: Insect-fungus mutualisms are highly diverse and particularly common in plant-colonizing insects. Here I extract some information from a comprehensive review on insect-fungus mutualisms and give an overview of the ones that are relevant to forestry. Services exchanged in insect–fungus mutualisms include nutrition, protection, and dispersal. Insects disperse fungi and can provide fungal growth substrates and protection. Obligate dependency has (a) resulted in the evolution of morphological adaptations in insects and fungi, (b) driven the evolution of social behaviors in some groups of insects, and (c) led to the loss of sexuality in some fungal mutualists..

 

Biography: Peter Biedermann is born in Austria. After studying in Graz, Vienna (A) and Bern (CH) he graduated with a Ph.D. on the social behavior of ambrosia beetles at the University Bern in 2012. After several postdocs at the USDA, UW Madison, Wageningen University and the Max-Planck Institute for Chemical Ecology in Jena, he established his own Emmy Noether Research Group at the University of Würzburg in 2017. Since April this year, he is a full professor for Forest Entomology and Protection at the University of Freiburg, Germany.

 

 

Title: Mycangia are essential to the ambrosia beetle-fungus symbioses

Speaker: Dr. Chase Mayers, School of Integrative Plant Science, Cornell University, New York, USA

 

Abstract: Ambrosia beetles bore tunnels into the sapwood of trees within which they inoculate and cultivate lush gardens of ambrosia fungi. These special ambrosia fungi are not found free living, yet each generation of ambrosia beetles typically fly to new trees and farm the very same fungal cultivar they were raised on. For more than 60 years, special pocket-like organs called mycangia (or mycetangia) have been appreciated as facilitating this cultivar persistence. However, mycangia are far from simple transport pockets. They are active organs that support fungal domestication and co-adaptation thanks to a “mycangium cycle” that imposes genetic bottlenecks and competitively excludes non-adapted fungi. Mycangia preserve fungal cultivars over background commensals, influence cultivar choice and persistence, may influence sociality, and facilitate convergent solutions to problems shared by other farming animals including humans. This talk serves to summarize an upcoming book chapter review of mycangia, and covers the present knowledge of ambrosia beetle mycangia as well as explaining why they are so essential to the many varied ambrosia beetle-fungus symbioses.

 

Biography: Chase Mayers was born in Louisiana, USA. After studying at Louisiana State University, he completed a Ph.D. in Microbiology at Iowa State University in 2018. His thesis work concerned the evolution of ambrosia fungi in the Ceratocystidaceae and their relationships with their beetle hosts. After a postdoctoral project on Rapid Ohia Death Ceratocystis mitogenomics, he received an NSF postdoctoral fellowship to work on the evolution of the endosymbiotic bacteria of arbuscular mycorrhizal fungi. Currently he is finishing up the latter project, and serving as a Teaching Support Specialist, in the School of Integrative Plant Science at Cornell University.

 

 

Title: Ips typographus and its fungal symbionts on native and non-native hosts

Speaker: Mr. Sifat Munim Tanin, Chair of Forest Entomology and Protection, University of Freiburg, Germany

 

Abstract: Ips typographus, one of the most damaging bark beetles in Europe, has never established in North America. The reason could be the lack of suitable host trees and fungi available in the new environment. Here we exposed this species to two different North American hosts (white and black spruce) and fungi associated with the North American spruce bark beetle Dendroctonus rufipennis. Ips typographus can colonize North American hosts and does not rely on its native fungi. It can detect and is attracted by various ophiostomatoid fungi.

 

Biography: Sifat Munim Tanin is born in Bangladesh. He has completed his Master's degree in Ecology from the Norwegian University of Life Sciences in 2020. Now he is working on developing his Ph.D. proposal on the fungal symbionts of bark beetles under the supervision of Peter Biedermann at the University of Freiburg, Germany.

 

 

Seminars for October 15, 2020

Title: You can run but you can´t hide: The sense of smell on predator-prey and host-parasitoid interactions

Speaker: Dr. Manuela Branco, Forest Research Center, School of Agriculture, University of Lisbon, Portugal

 

Abstract: The most important tool in the arsenal of insect predators and parasitoids to locate their prey is their sense of smell. This sense allows the detection of prey at both long and short distances regardless if they are visible or concealed, such as in bark crevices or inside tree trunk. Different volatile compounds may be used by predators and parasitoids, such as plant habitat volatile organic compounds, herbivore-induced plant volatiles (HIPV), prey pheromones as well as other prey odours.  The perception of these compounds shapes the evolutionary ecology of the predator/prey and host/parasitoid relationships. From a practical point of view we may use this knowledge for detection, monitoring or improving biological control.

 

Biography: M Branco graduated in forestry and obtained a PhD in Applied Biology. She teaches in the University of Lisbon. Her research cover aspects of the ecology of forest insects, population ecology and forest protection with emphasis on biological control.

 

 

Title: Specialising on the few or embracing the many - contrasting issues for bark beetle predators

Speaker: Dr. Jean-Claude Grégoire, Université libre de Bruxelles, Brussels, Belgium

 

Abstract: This talk will focus on the ecological and behavioural challenges facing two bark beetle predators with contrasted differences, the specialist Rhizophagus grandis (Coleoptera: Monotomidae), which attacks only one bark-beetle species, Dendroctonus micans (Kug.), and the generalist Thanasimus formicarius (Coleoptera: Cleridae), which is a bark-beetle generalist attacking a very large number of species on conifers or broadleaves.

 

Biography: JC Grégoire graduated in forestry and obtained a PhD in entomology. He studies basic and applied aspects of the ecology of forest insects (chemical ecology, predator-prey and parasitoid-host relationships, relationships to the host trees, reproductive strategies, dispersal) and works also in risk assessments for plant health.

 

 

Title: The infochemical detour, tracking host by proxy

Speaker: Dr. Sofia Branco, Centro de Estudos Florestais, Instituto Superior de Agronomia, Universidade de Lisboa, Portugal

 

Abstract: Egg parasitoids are faced with a major detectability problem because the host stage they depend on is usually inconspicuous and lack long-range cues that might be exploited by their enemies. Here we review how they overcome this difficulty by resorting to cues from other stages of their host species, in a process known as the infochemical detour. Results of studies conducted with Anaphes nitens (Hymenoptera, Mymaridae) are briefly discussed.

 

Biography: PhD in Environmental Sciences, B.Sc. in Environmental Biology (FCUL, UL) and M.Sc. in Medical Parasitology (IHMT, UNL). Currently working on the project "HOMED- HOlistic Management of Emerging forest pests and Diseases". During the PhD conducted research on the chemical ecology of the eucalyptus weevil, Gonipterus platensis, and its egg parasitoid, Anaphes nitens.

 

 

Seminars for October 29, 2020

Title: Chemically mediated plant-herbivore-microbe interactions in forests

Speaker: Dr. Almuth Hammerbacher, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, South Africa 

Abstract: Chemical interactions between plants and herbivores microbes are often studied as bipartite systems focusing on the effect of one interacting partner on the host plant. However, perennial plants, such as forest trees, interact with many microbes and herbivores during their life times and are often attacked simultaneously by insects and microbes of different life styles. In this seminar, we will consider two examples, where two organisms from different kingdoms simultaneously interact with a tree species to produce surprising outcomes.

Biography: Almuth Hammerbacher is a researcher at the Forestry and Agricultural Biotechnology Institute and a senior lecturer at the department of Zoology and Entomology at the University of Pretoria, South Africa. Her research focuses on the chemical communication of forest trees with insects and microbes.

 

Title: Monoterpenes mediate interactions between bark beetles and their fungal symbionts

Speaker: Dr. Dineshkumar Kandasamy, Max Planck Institute for Chemical Ecology, Germany

Abstract: Bark beetle outbreaks have decimated millions of hectares of conifer forests worldwide. Conifers have a formidable chemical defense against invading insects and pathogens. However, bark beetles overcome the tree defenses by mass attacks and by introducing symbiotic fungi in the tree phloem. While the role of pheromones in coordinating the mass attacks has been well studied in the past decades, the role of chemical communication between beetles and their symbiotic fungi is poorly understood. In this seminar, I talk about how the blue-stain fungi introduced by the European spruce bark beetle (Ips typographus) modify the chemistry of the Norway spruce (Picea abies) bark and alter the preference of beetles during host choice and feeding.

Biography: Dineshkumar Kandasamy is a post-doctoral fellow at the Max Planck Institute for chemical ecology in Jena, Germany. His research focuses on chemical interactions between conifer trees, bark beetles and their fungal symbionts.

 

Title: Tripartite interactions in poplar trees: herbivores feed on plant-pathogenic fungi for their own benefit

Speaker: Dr. Franziska Eberl, Max Planck Institute for Chemical Ecology, Germany

Abstract: In their natural habitat trees are not only attacked by a multitude of herbivorous insects, but are also constantly colonized by fungi and bacteria. However, the influence of microbes on tree-herbivore interactions is still widely overlooked. We studied the tripartite relationship of black poplar, the poplar rust fungus and the gypsy moth, and found that gypsy moth caterpillars preferred rust-infected over uninfected leaves. In particular, young caterpillars selectively fed on fungal spores, which contained high amounts of the feeding attractant mannitol. Ultimately, gypsy moth caterpillars benefited from the fungal infection of their host trees, as they contained lower amounts of defense compounds and higher amounts of nutritious components compared to uninfected trees, resulting in a faster larval development for the herbivore.

Biography: Franziska Eberl studied Biochemistry (B.Sc.) and Chemical Biology (M.Sc.) in Jena (Germany), and partly in Trondheim (Norway). During her Master thesis she already focused on the biotic interactions of black poplar, which she continued and intensified during her doctoral studies at the Max Planck Institute for Chemical Ecology. Since June 2020 Franziska is working as a scientific project coordinator and studies the effect of different artificial light sources on the phytochemistry of various plant species.

 

Seminars for November 12, 2020

Title: Behavioural and chemical ecology of Sirex noctilio

Speaker: Dr. Bernard Slippers, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, South Africa 

 

Abstract: The woodwasp Sirex noctilio is holometabolous and does not feed as an adult. As a result they are expected to experience strong selection for mate and host location. The dominant modalities that most insects use to interact with their abiotic and biotic environment are olfaction and vision. This seminar will provide an overview of S. noctilio and provide context for the accompanying seminars that will focus on the behavioural, visual and chemical ecology of S. noctilio in the context of mate and host location, population dynamics and geographical spread.

 

Biography: Dr. Slippers is a Professor in Genetics and Director of the Forestry and Agricultural Biotechnology Institute at the University of Pretoria. He was a founding member of the Global Young Academy, served as co-chair of this organization and was the founding Director of Future Africa. His research focuses on the molecular ecology and evolution of fungal communities, fungal pathogens and insect pests of trees as well as their symbioses and natural enemies.

 

 

Title: Body size, behaviour and sensory ecology of Sirex noctilio populations in Patagonia

Speaker: Dr. Juan C. Corley, Universidad Nacional del Comahue, Argentina 

 

Abstract: How insects interact with their environment, as well as their body size, strongly influences their ecological success. When given species arrive and establish in new areas, evolved life-history traits partly affect their invasion abilities and the impact they may have within the new range. I explore several of these attributes in the woodwasp Sirex noctilio (Hymenoptera: Siricidae) in Patagonia with the aim of helping us better understand population outbreaks and geographical spread of this invasive forest insect.

 

Biography: Dr. Corley is an Associate Professor of Behavioural and Population Ecology at the Universidad Nacional del Comahue in Bariloche, as well as a high-grade researcher in biology for CONICET, the National Science Council of Argentina. He also is founder and PI of the Insect Population Ecology Group at IFAB (Institute of Forest and Agricultural Research, INTA-CONICET) where he also serves as Vice-chairman.  Juan is the current Coordinator of the IUFRO Working Party on “Ecology and Management of Bark and Woodboring Insects” and soon-to-be Editor in Chief of Ecological Applications, as from 2021.  His research focuses on understanding behaviour, invasion and population ecology of forest insects and on how this basic biological knowledge can be used for sustainable pest management. Juan runs a blog where he discusses all thing ecological and related to the world of scientific publication.

 

 

Title: Reproductive biology of Sirex noctilio: Filling the gaps in chemical, visual and behavioural ecology

Speaker: Joséphine Queffelec and Quentin Guignard, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, South Africa 

 

Abstract: Reproductive biology is critical to understand the invasion success of insects, and this field can make an important contribution to their management. The behavioural and chemical ecology linked to the reproductive biology of Sirex noctilio has received little attention until the last decade, and many aspects remain poorly understood. In this talk we explore these knowledge gaps with respect to visual and chemical ecology, as well as mate choice. In particular, we will discuss our work on a possible sex-aggregation pheromone, visual adaptation to low light conditions and the effect of age and size on mating success.

 

Biography:

Joséphine Queffelec is a PhD student from FABI. Her work focuses on the influence of reproductive biology on the invasion dynamics of Sirex noctilio. She studies mating behaviours, sex determination and reproductive parasites and their effects on population dynamics.

Quentin Guignard is a PhD student from FABI. He focuses on the chemical and visual ecology of Sirex noctilio. He investigated the biology of the male pheromone and described the mechanisms underlying colour vision in the woodwasp.