Aurélien Sallé

University of Orléans | UO · Biology

Plant-manipulating herbivores can modify their host nutrients and defensive compounds to their own advantage. This generally results in enhanced performance of herbivores on modified tissues, but the anatomical and biochemical modifications undergone by host tissues could also modify the herbivores' behaviour. Phloeomyzus passerinii induces a react...

Oak declines are multifactorial processes in which bark and wood boring (BWB) beetles can act as major inciting factors, killing the weakened trees. Nonetheless, the current knowledge on the biology, ecology of these species is scattered and no efficient management strategies are currently available. Based on the existing literature and field obser...

Phloeomyzus passerinii is a major pest of poplar stands in Europe, North Africa and the Near East. This aphid feeds in the cortical parenchyma of different poplar species and hybrids, and can affect their growth and survival through unknown mechanisms. In some genotypes however, resistance prevents either the settlement or the development of aphid...

• Our aim is to present why the hypothesis, that Ophiostomatoid fungi play an important role in the establishment of most bark beetle species on living conifers, is valuable. • After summarizing knowledge about the relationships of bark beetles with conifers and fungi, we conclude that controversy results from misinterpretations when using fungal p...

Several Agrilinae species (Coleoptera: Buprestidae) are secondary pests of broadleaf forests, and some of them are also major invasive pests. These thermophilous borers are expected to be favoured by climate change and the global deterioration of forest health, and ultimately expand their range and damage. Flight behaviour and performance of these...

Aim Climate is a major driver of large-scale variability in biodiversity, as a likely result of more intense biotic interactions under warmer conditions. This idea fuelled decades of research on plant-herbivore interactions, but much less is known about higher-level trophic interactions. We addressed this research gap by characterizing both bird di...

Forest health is being challenged worldwide due to changing disturbance regimes. These changes could promote the abundance and diversity of secondary forest pests, like the Agrilinae (Coleoptera: Buprestidae) borers, which are frequently involved in oak decline in Europe. We assessed the contribution of environmental factors to local abundance and...

The genus Agrilus is one of the most diverse insect genera worldwide. The larval feeding activity causes extensive damage in both forests and orchards. In addition, more than 30 species have been introduced outside their native range so far, including the emerald ash borer Agrilus planipennis Fairmaire. Thus, the availability of efficient trapping...

Forest decline and dieback are growing phenomena worldwide, resulting in severe, large‐scale degradation of the canopy. This can profoundly alter the provision of trophic resources and microhabitats for canopy‐dwelling arthropods. In 2019, we assessed the effect of oak decline on the community of canopy‐dwelling Hymenoptera. We selected 21 oak stan...

Buprestids are an emerging threat to broadleaf forests across the world. Bronze birch borer ( Agrilus anxius , BBB) poses a serious threat to European birch species if the insect were to be introduced. Due to their cryptic lifestyle feeding on the vascular tissue of their host plants, buprestids and other wood borers can be difficult to observe or...

1. Forest decline and dieback are growing phenomena worldwide, resulting in severe, large-scale degradation of the canopy. This can profoundly alter the provision of trophic resources and microhabitats for canopy-dwelling arthropods. 2. In 2019, we assessed the effect of oak decline on the community of canopy-dwelling Hymenoptera. We selected 21 o...

Forest decline caused by climate change has been a growing challenge for European foresters for decades. The accumulation of tree-related microhabitats (TreMs) and deadwood during decline can enhance stand structural heterogeneity and provide crucial habitat features for many forest ecological guilds. We analysed changes in deadwood and TreM assemb...

Israelius querceti Marhic n. sp., is described. The genus Israelius Richards, 1952, never observed before in Western Europe, has been sampled during a survey of the entomofauna associated to the oak canopy, in the national forest of Vierzon (Cher department). - Israelius querceti Marhic n. sp. est décrit. Le genre Israelius Richards, 1952, jamais...

Les coupes sanitaires sont utilisées pour limiter l’impact sanitaire et économique des dépérissements forestiers. Dans cette revue de la littérature, nous avons examiné l’impact de ces coupes sur les services écosystémiques associés à la résilience des écosystèmes forestiers. Les coupes sanitaires affectent les communautés d’espèces forestières en...

Les effets des dépérissements sur la structure des peuplements, la quantité et la qualité des ressources, la composition des paysages et les communautés biologiques ont été analysés. Dans les pessières bavaroises, la richesse spécifique augmente généralement en zones perturbées, où certaines espèces rares réapparaissent. Dans les sapinières pyrénée...

Purpose of Review The increasing impact of droughts, wildfires and windstorms in temperate areas poses a significant challenge to the adaptation capacity of forests and their associated arthropod communities. Organisms, organic material, and environmental conditions occurring after disturbances, i.e. the disturbance legacies, shape arthropod commu...

Buprestids are an emerging threat to broadleaf forests across the world. Species such as emerald ash borer (EAB, Agrilus planipennis) seriously threaten ash (Fraxinus spp.) in North America and Europe. As it continues spreading west from European Russia, native European ash populations will suffer dramatic losses. Due to their cryptic lifestyle of...

Aim Climate is a major driver of large scale variability in biodiversity, as a likely result of more intense biotic interactions under warmer conditions. This idea fuelled decades of research on plant-herbivore interactions, but much less is known about higher-level trophic interactions. We addressed this research gap by characterizing both bird di...

Jewel beetles (Buprestidae) are primarily forest insects, and 155 species inhabit French forests. Several taxa are considered as heritage species in both broadleaf and conifer forests. The larvae of most species develop within the inner, living part of the bark; several species can also be opportunistic pests and cause severe damage to weakened hos...

Dans le bassin versant de la Loire, aux côtés de peuplements spontanés (subnaturels) apparaissent parfois des plantations forestières, en l’occurrence des peupleraies dans sa partie alluviale. Ces peuplements sont souvent décriés, notamment sur le plan de la biodiversité, car ils sont monospécifiques. Pourtant, une biodiversité peut leur être assoc...

Summary. – During an entomological inventory in the canopy of Oak stands, 15 species of Limoniidae (Diptera) have been collected in three different forests located in the centre of France (Loiret, Cher and Allier). All species are new to the department, and the species Helius calviensis Edwards, 1928, previously known from Corsica only in France, i...

Global change challenges the adaptive potential of forests. Large-scale alterations of forest canopies have been reported across Europe, and further modifications are expected in response to the predicted changes in drought and windstorm regimes. Since forest canopies are dynamic interfaces between atmosphere and land surface, communities of canopy...

Aim The strength of species interactions is traditionally expected to increase toward the Equator. However, recent studies have reported opposite or inconsistent latitudinal trends in the bottom‐up (plant quality) and top‐down (natural enemies) forces driving herbivory. In addition, these forces have rarely been studied together thus limiting previ...

Key message Unprecedented forest declines and diebacks are expected worldwide in response to global change. Insects can trigger or contribute to these disturbances, which can in turn have either beneficial or detrimental retroactive cascading effects on insect communities. However, we are still unsure of the effects that pests will have on these di...

Trees in a state of decline exhibit a reduced foliage density and accumulate dead branches in their crowns. Consequently, forest decline can markedly affect both the habitats and sources of food for canopy-dwelling insects. The decline-induced increase in canopy openness may also modify the understory, shrub and ground layers, and have cascading ef...

Context: Decline in a context of climate change is expected to induce considerable changes in forest structure, potentially affecting habitat opportunities and trophic resources for numerous species. Nonetheless, the consequences of decline on forest biodiversity have rarely been studied. Aim: We aimed to characterize the impact of oak decline...

Au cours d’une étude sur l’impact du dépérissement sur l’entomofaune des canopées de Chênes dans différentes forêts du Centre – Val de Loire, un individu de Nineta inpunctata (Reuter, 1894), une espèce de Chrysope très rare en France et en Europe, a été capturé. During a study on the impact of decline on the entomofauna of oak canopies in different...

Les agriles sont généralement des parasites de faiblesse qui révèlent le stress subi par des hôtes affaiblis. Ils colonisent des branches cassées comme des troncs dépérissants et se maintiennent ainsi facilement à un niveau endémique dans les houppiers et le sous-étage. Les forestiers et des arboriculteurs d’Europe, d’Amérique et d’Asie redoutent n...

• The woolly poplar aphid Phloeomyzus passerinii Signoret (Aphididae: Phloeomyzinae) is a major pest of poplar plantations. We hypothesized that recent temperature increases may have contributed to the emergence and subsequent northward expansion of outbreaks in France. • We reared P. passerinii at four temperatures to estimate its thermal requirem...

Insectes chatoyants, les agriles présentent une exceptionnelle diversité taxinomique malgré un aspect relativement uniforme et des cycles biologiques peu diversifiés. C’est leur penchant immodéré pour les arbres affaiblis, mais vivants, qui les rend redoutables, d’autant plus que les changements climatiques et la mondialisation leur permettent d’él...

The pressing need to identify the ecological consequences of climate changes boosted the development of macroecological approaches as well as climatological tools. Nevertheless, the major pitfall remains that the actual climatic conditions experienced by organisms in their microhabitat and across their home range are largely ignored. In this contex...

Insectes chatoyants, les agriles présentent une exceptionnelle diversité taxinomique malgré un aspect relativement uniforme et des cycles biologiques peu diversifiés. C’est leur penchant immodéré pour les arbres affaiblis, mais vivants, qui les rend redoutables, d’autant plus que les changements climatiques et la mondialisation leur permettent d’él...

Successful plant colonization by parasites requires the circumvention of host defenses, and sometimes a reprogramming of host metabolism, mediated by effector molecules delivered into the host. Using transcriptomic and enzymatic approaches, we characterized salivary glands and saliva of Phloeomyzus passerinii, an aphid exhibiting an atypical feedin...

Aim The strength of species interactions is traditionally expected to become stronger toward the Equator. However, recent studies have reported opposite or inconsistent latitudinal trends in the bottom-up (plant quality) and top-down (natural enemies) forces driving insect herbivory, possibly because these forces have rarely been studied concomitan...

Context Decline in a context of climate change is expected to induce considerable changes in forest structure, potentially affecting habitat opportunities and trophic resources for numerous species. Nonetheless, the consequences of decline on forest biodiversity have rarely been studied. Aim We aimed to characterize the impact of oak decline on di...

Plant manipulation by herbivores requires fine-tuned reprogramming of host metabolism, mediated by effector molecules delivered by the parasite into its host. Secretomes of plant-manipulating animals and their impact on host-plants have been rarely studied. We characterized, with transcriptomic and enzymatic approaches, salivary glands and saliva o...

Tree-killing bark beetles are the most economically important insects in conifer forests worldwide. However, despite >200 years of research, the drivers of population eruptions and crashes are still not fully understood and the existing knowledge is thus insufficient to face the challenges posed by the Anthropocene. We critically analyze potential...

The poplar wooly aphid, Phloeomyzus passerinii, has recently become a main pest for poplar stands in France. Following pullulations of this insect, growth retardation is observed, sometimes with massive mortality amongst mature trees. Observed initially in southwestern France in the mid 90s, damage was later observed in other poplar tree growing ar...

Plant manipulation by herbivores requires fine-tuned reprogramming of host metabolism, mediated by effector molecules delivered by the parasite into its host. While plant galls may represent the epitome of plant manipulation, secretomes of gall-inducers and their impact on host-plants have been rarely studied. We characterized, with transcriptomic...

There is tremendous diversity of interactions between plants and other species. These relationships range from antagonism to mutualism. Interactions of plants with members of their ecological community can lead to a profound metabolic reconfiguration of the plants' physiology. This reconfiguration can favour beneficial organisms and deter antagonis...

Aphids can affect the growth or architecture of their host-trees, but rarely challenge their survival. Nonetheless, the woolly poplar aphid, Phloeomyzus passerinii, can kill healthy, mature poplars during outbreaks. Trees fail to open their buds and flush their leaves in the spring following a severe infestation. This insect develops on poplar trun...

Context: Phloeomyzus passerinii is a major pest of poplar plantations in Europe, and the plantation of resistant poplar genotypes is regarded as the best long-term management strategy for this pest. This requires a sound knowledge of the interactions among the pest, its host and their environment. Aims: Here we review the recent advances aiming at...

Most bark beetles living on standing trees must overcome the natural resistance of their host to succeed in colonization. For this they perform mass attacks to reach a critical threshold of attack density (CTAD) above which host defences are exhausted. However, this strategy can result in an intense intraspecific competition during larval developme...

Phytophagous insects have developed mechanisms of various complexity levels to utilize plants in spite of the barriers that plants have built to resist aggressions. Plant exploitation, the simplest level, is the use of plant defence chemicals for the benefit of insects. It is illustrated by the use of plant toxins for defence against predators. The...

Phytophagous insects have developed mechanisms of various complexity levels to utilize plants in spite of the barriers that plants have built to resist aggressions. Plant exploitation, the simplest level, is the use of plant defence chemicals for the benefit of insects. It is illustrated by the use of plant toxins for defence against predators. The...

1. Global warming is predicted to enhance the development rate and increase the number of generations in multivoltine insects. For secondary forest pests, such as the pine bark beetle Ips sexdentatus, the resulting increase in population level could trigger more frequent outbreaks. However, this positive effect could be outweighed by a temperature-...

Several native species of aphids, coccids and bugs can affect trees in the Mediterranean Basin. The prominent species on broadleaved trees are Phylloxera quercus and Kermes vermilio for evergreen oaks, and Phloeomyzus passerinii for poplars. On conifers, Haematoloma dorsatum and three species of Leucaspis could be considered as pine pests. Most of...

The prominent buprestid and longhorn beetles damaging trees in the Mediterranean Basin are Cerambyx welensii, Prinobius myardi and Cerambyx cerdo, especially C. cerdo mirbeckii, for the Cerambycidae, and Coraebus florentinus, Coraebus undatus and Trachypteris picta for the Buprestidae. Most of them are considered as secondary pests, colonizing the...

Introduction: Phloeomyzus passerinii is a tree-dwelling aphid colonizing the trunks of poplars (Populus sp.). This species has several peculiarities. It occupies a basal position in the phylogeny of Aphididae, and it is responsible for spectacular diebacks of poplar plantations in Europe. Nonetheless, as an emerging pest, little is known about the...

Le puceron lanigère du peuplier est un ravageur important des peupleraies françaises. Lors de pullulations, cet insecte peut entraîner des mortalités massives, probablement en épuisant les réserves des arbres. Des niveaux variables de sensibilité au puceron sont observés sur les différents cultivars de peuplier plantés en France. Un test de sensibi...

Successful plant manipulation by herbivores requires a reconfiguration of the primary and secondary metabolisms of the host-plant. Water deficit is generally predicted to negatively affect the development of gall-inducing insects, by impairing their ability to remodel the primary metabolism of their host. We assessed whether host genotype could mod...

1. Phytophagous insects frequently manipulate their host-plant to improve their immediate environment. This generally implies substantial modifications of host metabolism, and sometimes an alteration of nitrogen allocation within the host-plant. However, the outcome of plant manipulation on amino acid or protein content can be modulated by environm...

Climate change in recent decades has been directly or indirectly involved in changing the life-history and population levels of many endemic forest insect species, leading to unexpected and unprecedented outbreaks. In spite of diffi culties in assessing the complex impact of climate on insect communities, evaluating the effect of climate warming on...

The woolly poplar aphid, Phloeomyzus passerinii (Signoret) (Hemiptera: Aphididae), is a major pest of poplar plantations in the Mediterranean basin and the Near East. Aphids colonize poplar trunks and feed upon the cortical parenchyma. Despite the economic importance of poplar, little is known about the mechanisms involved in poplar resistance to t...

Le puceron lanigère du peuplier. Phloeomyzus passerinii est un ravageur important des peupleraies du sud de l'Europe, du Proche-Orient et d'Afrique du Nord. Après une insertion de ses stylets, à la fois intercellulaire et intracellulaire, il se nourrit exclusivement dans le parenchyme cortical du tronc des peupliers. Durant les pullulations, ce puc...

The woolly poplar aphid, Phloeomyzus passerinii (Signoret) (Sternorrhyncha: Aphididae), causes the most damage to poplars in southern Europe and the Near East as outbreaks can lead to massive mortality in mature stands. Previous studies, conducted on poplar cuttings or young trees, showed that resistance varied depending on the poplar genotype. How...

1 Pityogenes chalcographus L. (Coleoptera: Scolytinae) causes damage in European coniferous forests, primarily on Picea abies L. Karst., but is also recorded on other native and exotic Pinaceae species. Estimating the adequacy between adult preference and larval performance of this beetle among its host-range, as well as the influence of plant taxo...

Planting exotic conifers offers indigenous forest insects an opportunity to extend their host range and eventually to become significant pests. Knowing the ecological and evolutionary modalities driving the colonisation of exotic tree species by indigenous insects is thus of primary importance. We compared the bark beetle communities (Coleoptera: C...

Considering the key role of Monochamus galloprovincialis (Olivier) (Coleoptera: Cerambycidae) in the dispersion of the pine wood nematode, Bursaphelenchus xylophilus (Steiner & Bührer) Nickle (Nematoda: Aphelenchoidea), in Europe, defining the host spectrum and preference of M. galloprovincialis is of primary importance for forest management. There...

We examined the influence of seasonal water stress on the resistance of Pinus yunnanensis (Franch.) to inoculation with Leptographium yunnanense, a pathogenic fungus associated with the aggressive bark beetle, Tomicus n. sp. Experiments took place between October 1997 and November 1999 in two plots located at the top and at the foot of a hill in Sh...

Abstract 1. Variations in developmental conditions of bark beetles, particularly intraspecific competition, can induce morphological and physiological modifications in the offspring. It is hypothesised that intraspecific competition could also affect host selection behaviour. Such behavioural changes might be manifested in response to host (alpha-p...

The phylogeography of the bark beetle Ips typographus was assessed using five microsatellite markers. Twenty-eight populations were sampled throughout Europe on the host tree Picea abies. I. typographus showed very low levels of genetic diversity, and the study revealed a lack of genetic structure across Europe. No significant barrier to gene flow...