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Total phenols, flavonoids, flavonols, and flavanols of the methanolic extract of the aerial part of Artemisia herba-alba were determined. The extract was analyzed by liquid chromatography with photodiode array coupled with electrospray ionisation mass spectrometry and allowed to identify of 10 phenolic compounds. Apigenin-6-C-glycosyl flavonoids and caffeoylquinic acids were identified. Chlorogenic acid and 1,4 dicaffeoylquinic acid being the major constituents. The essential oil obtained by hydrodistillation was analyzed by gas chromatography-mass spectrometry. Twenty-three compounds, representing 97.8% of the total oil, were identified. The most abundant components were βthujone (41.9%), α-thujone (18.4%), and camphor (13.2%). Methanolic extract and essential oil exhibited a considerable antioxidant activity as evaluated by 2,2-diphenyl-pycrilhydrazil hydrate scavenging activity, reducing power, β-carotene bleaching test, and chelating ability. The methanolic extract was found to be more efficient, while the essential oil exhibited the highest acetylcholinesterase inhibitory activity. Analysis of the antibacterial activity showed that A. herba-alba methanolic extract and essential oil are efficient against gram positive and gram negative bacteria.

The relationship between the chemical composition and the biological activities is confirmed by the present findings. Therefore the potential uses of these essential oils as bioinsecticides can be considered as an alternative to the use of synthetic products.

Numerous studies have shown that the genetic diversity of species inhabiting temperate regions has been shaped by changes in their distributions during the Quaternary climatic oscillations. For some species, the genetic distinctness of isolated populations is maintained during secondary contact, while for others, admixture is frequently observed. For the winter moth (Operophtera brumata), an important defoliator of oak forests across Europe and northern Africa, we previously determined that contemporary populations correspond to genetic diversity obtained during the last glacial maximum (LGM) through the use of refugia in the Iberian and Aegean peninsulas, and to a lesser extent the Caucasus region. Missing from this sampling were populations from the Italian peninsula and from North Africa, both regions known to have played important roles as glacial refugia for other species. Therefore, we genotyped field‐collected winter moth individuals from southern Italy and northwestern Tunisia—the latter a region where severe oak forest defoliation by winter moth has recently been reported—using polymorphic microsatellite. We reconstructed the genetic relationships of these populations in comparison to moths previously sampled from the Iberian and Aegean peninsulas, the Caucasus region, and western Europe using genetic distance, Bayesian clustering, and approximate Bayesian computation (ABC) methods. Our results indicate that both the southern Italian and the Tunisian populations are genetically distinct from other sampled populations, and likely originated in their respective refugium during the LGM after diverging from a population that eventually settled in the Iberian refugium. These suggest that winter moth populations persisted in at least five Mediterranean LGM refugia. Finally, we comment that outbreaks by winter moth in northwestern Tunisia are not the result of a recent introduction of a nonnative species, but rather are most likely due to land use or environmental changes.

BackgroundEssential oils extracted from aromatic and medicinal plants have many biological properties and are therefore an alternative to the use of synthetic products. The chemical composition of essential oils from two medicinal plants (Eucalyptus globulus and E. lehmannii) was determined and, their insecticidal effects on the third and fourth larval stages of Orgyia trigotephras were assessed.ResultsLarvae were collected from Jebel Abderrahmane (North-East of Tunisia), conserved in groups of 50/box (21 × 10 × 10 cm) at a temperature of 25°C. Larvae were tested for larvicidal activities of essential oils. Each oil was diluted in ethanol (96%) to prepare 3 test solutions (S1 = 0.05%, S2 = 0.10% and S3 = 0.50%). Essential oils were used for contact, ingestion and Olfactory actions and compared to reference products (Bacillus thuringiensis and Decis). Olfactory action of essential oils shows that larvae mortality is higher than contact action, lower than ingestion action. MTM and FTM of S3 of E. lehmannii were respectively 1 h 32 min and 1 h 39 min are higher than those of E. globulus (MTM = 51 min and FTM = 1 h 22 min 34 sec). Contact action of E. lehmannii oil shows low insecticidal activity compared to E. globulus. MTM are respectively (1 min 52 sec and 1 min 7 sec), FTM are (2 min 38 sec, 1 min 39 sec), are the shortest recorded for S3, on the third stage of larvae. The fourth stage of larvae, MTM are (2 min 20 sec and 2 min 9 sec), FTM are (3 min 25 sec, 3 min 19 sec). Ingestion action of essential oils is longer than the contact action, since the time of death exceeds 60 minutes for all species.ConclusionResults shows that essential oils have a toxic action on nerves leading to a disruption of vital system of insects. High toxic properties make these plant-derived compounds suitable for incorporation in integrated pest management programs.

Abstract& Key message During outbreak, a discrepancy between larval performance and the main host used for egg laying was found in Orgyia trigotephras. It results mostly from intraspecific competition, but reduced egg mortality on the less suitable host plant may play a secondary role. & Context Host range of polyphagous herbivores often comprises plants of low nutritional quality, which may however provide other benefits to the animal. Understanding the effect of host plants use on insect fitness and its population dynamics are central questions in insect-plant ecology. O. trigotephras Boisduval is a polyphagous Mediterranean defoliator. During outbreaks, larvae are frequently found on two unrelated host species, Pistacia lentiscus L. and Quercus coccifera L. & Aim The aim of this study was to clarify the effect of population density on host use and the effects of host tree on insect performance. & Methods The realized fecundity and egg mortality were measured during 3 years showing different population levels of the defoliator. Larval performance on the two host species was analyzed. & Results Larvae fed on Q. coccifera had faster development, lower mortality, higher female/male ratio, and higher fecundity than larvae fed on P. lentiscus. Yet, at high population densities, under high intraspecific competition, P. lentiscus was the most used for egg laying. During outbreak, higher levels of parasitism by Aprostocetus sp. and predation by Coccidiphila rungsella Nel and Brusseaux were found on eggs laid on Q. coccifera compared to those laid on P. lentiscus. & Conclusions The results indicate a discrepancy between host use and larvae performance, possibly ruled by resources exploitation and intraspecific competition. The reduced egg Handling Editor: Aurelien SalleContribution of co-authors Olfa EZZINE: project design, field and laboratory data collection, data analysis, and paper writing. Manuela BRANCO: project design, data analysis, and paper writing. Claire VILLEMANT and Stefan SCHMIDT: data analysis and paper writing. Said NOUIRA and Mohamed Lahbib BEN JAMÂA: supervisors.Electronic supplementary material The online version of this article (doi:10.1007/s13595-015-0484-7) contains supplementary material, which is available to authorized users. predation on P. lentiscus during outbreaks might also provide an indirect benefit to the insect.

& Key message Operophtera brumata L. performance varies among three Mediterranean oak species. Quercus canariensis Willd is more susceptible to infestation probably due to its (i) early leafing, (ii) high nutritional value for the larvae, and (iii) widespread abundance. & Context Larvae of Operophtera brumata were observed for the first time in an outbreak in Tunisia affecting Quercus canariensis, Quercus afares Pomel, and Quercus suber L. Due to its polyphagous nature and the important ecological and economic damage it causes, it is most relevant to understand its interaction with North African oaks species. & Aims In this paper, budburst phenology of the three oak species, larval performance, and genetic patterns of O. brumata were studied in northwestern Tunisia. & Methods In the spring of 2010, 2011, and 2012, budburst phenology of host species and larval densities were monitored weekly. Larval performance of O. brumata on the three oak species was analyzed. DNA extraction, PCR, and DNA sequencing were performed. & Results Budburst of Q. canariensis and Q. afares was earlier than Q. suber. Q. canariensis was the most infested host. Larvae which fed on Q. canariensis had faster development, lower mortality, and higher pupal weight than larvae fed on Q. afares and Q. suber. Molecular analyses showed that Tunisian haplotypes were not different from those in Spain, Italy, and Germany. & Conclusion Results indicated differences in larval performance. Q. canariensis was the most favorable host species. Its high density in the field and early leafing coinciding with larval hatching made this species particularly susceptible.

Background The polyphagous tachinid Compsilura concinnata is an endoparasitoid fly recorded as attacking larvae of Lepidoptera and Hymenoptera. Larvae of Orgyia trigotephras [Lepidoptera: Erebidae] were collected from northern Tunisia and reared in the laboratory. Results Adult flies that emerged from these larvae were identified on the basis of morphological description and DNA analysis (PCR) as Compsilura concinnata. Conclusion Compsilura concinnata is recorded here for the first time from Orgyia trigotephras in Tunisia. This species could be of great interest as a potential biological control agent of pests in Tunisia and neighboring countries.