Biodiversités « utile » et « nuisible » dans les agrosystèmes : importance pour la lutte biologique par conservation

La lutte biologique par conservation repose sur la mise en place d’aménagements dans ou autour de parcelles cultivées ou de modifications des pratiques culturales de façon à favoriser la régulation des ravageurs des cultures par des auxiliaires de lutte biologiques indigènes. Pour être efficaces, les méthodes de lutte biologique par conservation nécessitent toutefois plusieurs pré-requis : (i) une bonne compréhension de la biodiversité associée aux agrosystèmes, (ii) l’optimisation des échanges entre la culture et les autres composantes de l’agrosystème, (iii) la prise en compte d’éventuels effets non-intentionnels associés aux auxiliaires favorisés. Ces trois points sont discutés dans le cadre d’un programme en cours dont l’objectif est d’évaluer l’intérét d’une plante méditerranéenne, l’inule visqueuse Dittrichia viscosa L. (W. Greuther) (Asteraceae), pour la régulation de ravageurs dans deux agrosystèmes, l’oliveraie et la culture sous serres

Multilocus phylogeny and ecological differentiation of the "Eupelmus urozonus species group" (Hymenoptera, Eupelmidae) in the West-Palaearctic

Background: The ecological differentiation of insects with parasitic life-style is a complex process that may involve phylogenetic constraints as well as morphological and/ or behavioural adaptations. In most cases, the relative importance of these driving forces remains unexplored. We investigate here this question for the “ Eupelmus urozonus species group ” which encompasses parasitoid wasps of potential interest in biological control. This was achieved using seven molecular markers, re liable records on 91 host species and a proxy of the ovipositor length. Results: After using an adequate partitioning scheme, Maximum likelihood and Bayesian approaches provide a well-resolved phylogeny supporting the monophyly of this species group and highlighting its subdivision into three sub-groups. Great variations of both the ovipositor length and the host range (specialist versus generalist) were observed at this scale, with these two features being not significantly constrained by the phylogeny. Ovipositor length was not shown as a significant predictor of the parasitoid host range. Conclusions: This study provides firstly the first evidence for the strong lability of both the ovipositor's length and the realised host range in a set of phylogeneticall y related and sympatric species. In both cases, strong contrasts were observed between sister species. Moreover, no significant correlation was found between these two features. Alternative drivers of the ecological differentiation such as interspecific interactions are proposed and the consequences on the recruitment of these parasitoids on native and exotic pests are discussed

Does the Choice of Extraction Site During Minimally Invasive Colorectal Surgery Change the Incidence of Incisional Hernia? Protocol for a Systematic Review and Network Meta-Analysis.

BACKGROUND: Various sites are used for specimen extraction in oncological minimally invasive colorectal surgery. The objective is to determine if the choice of extraction site modulates the incidence of incisional hernia (IH). METHODS/DESIGN: A systematic review will be performed in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. MEDLINE, Embase and CENTRAL will be searched to look for original studies reporting the incidence of IH after minimally invasive colorectal surgery. Studies will be excluded from the analysis if: 1) they do not report original data, 2) the outcome of interest (incidence of incisional hernia) is not clearly reported and does not allow to extrapolate and/or calculate the required data for network meta-analysis, 3) they include pediatric patients, 4) they include a patients' population with a conversion rate to laparotomy >10%, 5) they do not compare at least two different extraction sites for the operative specimen, 6) they report patients who underwent pure (and not hybrid) natural orifice transluminal endoscopic surgery (NOTES). Network meta-analysis will be performed to determine the incidence of IH per extraction site. DISCUSSION: By determining which specimen extraction site leads to reduced rate of IH, this systematic review and network meta-analysis will help colorectal surgeons to choose their extraction site and reduce the morbidity and costs associated with IH. REGISTRATION: The systematic review and meta-analysis protocol is registered in the International Prospective Register of Ongoing Systematic Reviews (PROSPERO) with number CRD42021272226. HIGHLIGHTS: Various sites are used for specimen extraction in oncological minimally invasive colorectal surgery, and the choice of the site may probably modulate the incidence of incisional hernia.The present protocol aims to design a systematic review which will identify original studies comparing two extraction sites during minimally invasive colorectal surgery in terms of incidence of incisional hernia.Network meta-analysis will be performed to determine the incidence of IH per extraction site

Torymus sinensis and its close relatives in Europe: a multilocus phylogeny, detailed morphological analysis, and identification key

The introduction of the biological control agent Torymus sinensis Kamijo (Hymenoptera, Chalcidoidea, Torymidae) to control the populations of the chestnut gall wasp Dryocosmus kuriphilus Yasumatsu (Hymenoptera, Cynipidae) is considered one of the successful programs in biological control. The species was involved in interspecific hybridisation in Japan and the specimens imported into Europe were derived from this hybrid lineage, showing signs of introgression. The discovery of mitochondrial haplotypes or possible Enolase haplotypes from T. beneficus or of specimens with shorter ovipositor does not necessarily imply that T. beneficus is present in Europe, only that the European specimens are of hybrid origin. Of the native European Torymus species associated with D. kuriphilus, the molecular and morphometric results indicate Torymus notatus (Walker) as the closest species to T. sinensis. The two are part of the same species-group (cyaneus group), are nested together in the multivariate ratio analysis and are the closest genetically based on all three nuclear markers: Enolase (1.5% divergence), Wingless (2%) and ITS2 (13%). However, on the mitochondrial marker COI the closest species is Torymus rubi (Schrank) at 9.9% divergence. As such, T. notatus is the most likely candidate for accidental interspecific hybridisation if this is to happen in Europe. We provide an illustrated identification key for the European species of Torymus associated with D. kuriphilus, an important but lacking tool for biological control programs

Patients’ related sexual outcomes in colorectal surgery

BackgroundPatients undergoing colorectal surgery (CRS) have an increased risk of developing sexual disorders, attributed to different mechanisms. In this context, sexual function (SF) assessment of patients before and after surgery is essential: to identify risk factors for sexual disorders as well as to minimize their impact on overall quality of life (QoL), allowing them a satisfying relationship and sexual life.Material and methodsPatients over 18 years of age who underwent a CRS in the University Hospital of Geneva, Switzerland, between June 2014 and February 2016 were included. Our main objective was to compare and analyze the evolution of SF, QoL, and marital satisfaction (MS) before and after CRS. Specific and standardized tests were used.ResultsA cohort of 72 patients with a median age of 58.73 was analyzed. The majority of CRS was elective (91.5%). A percentage of 52.8% of patients underwent surgery for oncological reasons. There was no statistical difference in SF, sexual QoL, and MS before and after elective or emergency CRS for men. Interestingly, a significant decrease in women’s SF (FSFI) as well as their satisfaction within their couple (Locke–Wallace) until 12 months after surgery was found (p = 0.021). However, they showed a steady SF (GRISS) within their couple until 12 months after surgery.ConclusionRegarding knowledge about difficulties to talk about this intimate topic and gender differences, this general overview raises the question of the necessity to introduce in a long-course follow-up different methods of sexual health assessment with specific stakeholders

Nab-PIPAC: a phase IB study protocol of intraperitoneal cisplatin and nab-paclitaxel administered by pressurised intraperitoneal aerosol chemotherapy (PIPAC) in the treatment of advanced malignancies confined to the peritoneal cavity

Introduction: Intraperitoneal dissemination is a major problem resulting in very poor prognosis and a rapid marked deterioration in the quality of life of patients. Pressurised intraperitoneal aerosol chemotherapy (PIPAC) is an emergent laparoscopic procedure aiming to maximise local efficacy and to reduce systemic side effects. Methods and analysis: Nab-PIPAC, a bicentre open-label phase IB, aims to evaluate safety of nab-paclitaxel and cisplatin association using in patients with peritoneal carcinomatosis (PC) of gastric, pancreatic or ovarian origin as ≥1 prior line of systemic therapy. Using a 3+3 design, sequential intraperitoneal laparoscopic application of nab-paclitaxel (7.5, 15, 25, 37.5, 52.5 and 70 mg/m2) and cisplatin (10.5 mg/m2) through a nebuliser to a high-pressure injector at ambient temperature with a maximal upstream pressure of 300 psi. Treatment maintained for 30 min at a pressure of 12 mm Hg and repeated4-6 weeks intervals for three courses total.A total of 6-36 patients are expected, accrual is ongoing. Results are expected in 2024.The primary objective of Nab-PIPAC trial is to assess tolerability and safety of nab-paclitaxel and cisplatin combination administered intraperitoneally by PIPAC in patients with PC of gastric, pancreatic or ovarian origin. This study will determine maximum tolerated dose and provide pharmacokinetic data. Ethic and dissemination: Ethical approval was obtained from the ethical committees of Geneva and Vaud (CCER-2018-01327). The study findings will be published in an open-access, peer-reviewed journal and presented at relevant conferences and research meetings. Trial registration number: NCT04000906.</p

Evidence for a cryptic parasitoid species reveals its suitability as a biological control agent.

Uncertainty about the taxonomic status and the specificity of a species commonly prevent its consideration as a candidate for biological control of pest organisms. Here we use a combination of molecular analysis and crossing experiments to gather evidence that the parasitoid wasp Ganaspis brasiliensis, a candidate for biological control of the invasive spotted wing drosophila Drosophila suzukii, is a complex of at least two cryptic species. Complementary experiments demonstrate that individuals from one genetic group readily parasitize several drosophila species regardless of their food source while individuals from the other one are almost exclusively specific to larvae feeding in ripening fruits. Because only D. suzukii attacks ripening fruits in its area of invasion, parasitoids from this second group appear to be well suited as a biological control agent. Our study demonstrates the need for a combination of biosystematics with biological and ecological investigations for the development of safe and efficient biological control programs

Utilization of microcosms to test invasion biology hypotheses

Comprendre les facteurs déterminant le succès ou l’échec des processus invasifs est un objectif majeur en biologie de l’invasion. De nombreux travaux théoriques se sont intéressés aux composantes écologiques et évolutives de ces facteurs. Cependant, les tests d’hypothèses associés à une démarche expérimentale restent rares. La plupart des résultats empiriques sont issus de l’analyse a posteriori d’invasions fortuites et ne permettent donc, au mieux, que des approches corrélatives. Dans cet article, nous discutons de la pertinence des microcosmes, i.e. des environnements simplifiés, contrôlés et reproductibles, comme alternatives aux introductions expérimentales en milieu naturel. En nous basant sur une synthèse de la littérature, nous présentons les avantages et limites des approches en microcosmes pour l'étude des invasions biologiques. Notre analyse se concentre sur les publications impliquant des populations en dynamique transitoire après un goulot d’étranglement et/ou soumises à un challenge adaptatif, deux caractéristiques clés des processus invasifs. Malgré le nombre encore réduit de telles études, leur intérêt a été montré pour explorer les influences des caractéristiques de l’aire envahie (les conditions environnementales ainsi que leur hétérogénéité spatiale ou temporelle). Dans une moindre mesure, les microcosmes ont également permis de tester l’influence des caractéristiques des populations introduites et de la communauté envahie. Cependant, ils doivent être utilisés avec précaution car ils ne permettent pas de reproduire la complexité des milieux naturels. Les expériences en microcosmes sont donc complémentaires aux études théoriques et à celles menées en populations naturelles et contribuent à renforcer la valeur prédictive de la biologie de l’invasion en liant théorie et expérimentation.Understanding the factors underlying establishment and spread of exotic species in order to predict invasion risks is a major goal in invasion biology. Many theoretical studies investigated the ecological and evolutionary components of these factors and their impact on the invasive process. Yet, hypothesis tests through experimental approaches are still scarce because of the practical and ethical difficulties associated with the introduction of exotic species in nature. Thus, most empirical results come from a posteriori analyses of fortuitous invasions, which allow correlative approaches at best and give no information about invasion failures. In this paper, we propose microcosms, i.e. reproducible controlled simplified environments, as an alternative to experimental introductions in natura. From a review of the literature, we discuss the distinctive features of microcosms to test theoretical predictions about invasion. Our analysis focuses on studies involving populations in transitory dynamics after a demographic bottleneck and/or subject to an adaptive challenge, two key characteristics of invasive processes. Despite their small number, these studies have been used successfully to explore the influences of various factors, mainly related to the introduction site characteristics (its abiotic conditions and their spatial and temporal heterogeneity), and to a lesser extent to the introduced individuals themselves (propagule pressure, genetic diversity and adaptations in the introduced population) or the invaded community. We argue that microcosms, as model systems, can be powerful tools to test theoretical hypotheses. They must however be used with care, as they do not account for the same complexity as natural systems. They are thus complementary to theoretical studies and field surveys, and contribute to reinforce the predictive value of invasion biology by linking theory and experimentation