Giuseppino Sabbatini Peverieri

SEARCHING FOR NATIVE EGG-PARASITOIDS OF THE INVASIVE ALIEN SPECIES HALYOMORPHA HALYS STÅL (HETEROPTERA PENTATOMIDAE) IN SOUTHERN EUROPE

Halyomorpha halys is an invasive species, originating from East Asia, which was accidentally introduced in some areas of North America and Europe, where severe damages to different vegetable crops and fruit plants were recorded. Several studies in different countries focused on the possibility to apply biological control by means of egg- parasitoids. The main egg-parasitoids in the original area are unfortunately non-specific and thus the application of classical biological control is questionable. On the other hand, the possibility of using augmentative biological control by native egg-parasitoids able to exploit the new host is an interesting possibility in both Europe and the USA. In a preliminary assay, frozen egg masses of H. halys were exposed in the field in Central Italy. Results showed that some eggs were exploited by parasitoids belonging to the species Anastatus bifasciatus and Ooencyrtus telenomicida . Therefore, different native egg-parasitoids species widespread in Europe were tested in the laboratory in order to explore their ability to parasitize H. halys eggs. To this end, no-choice tests were carried out in climatic chambers (26°C, 70%RH, 16:8 L:D) in order to evaluate the parasitization potential of females collected in the wild. Conducted tests pointed out that A. bifasciatus and especially O. telenomicida may be potential candidates for the biological control of H. halys . In particular, O. telenomicida was able to parasitize the 35.56% of the exposed host eggs in the lab tests. New adults successfully emerged from the 22.92% of the eggs, and on the whole, this egg-parasitoid caused a significant hatching reduction of the H. halys eggs (more than 70%). Conversely, Telenomus chloropus and Ooencyrtus pityocampae were less promising species as biocontrol agents of this agricultural pest. Preliminary trials in pear orchards consisting of field releases of laboratory-reared specimens of O. telenomicida, one of the potential candidates for biological control, showed that this parasitoid is actually able to discover egg masses of H. halys (sentinel frozen egg masses) and to successfully parasitize them.

Managing outbreaks of the citrus long-horned beetle Anoplophora chinensis (Forster) in Europe: molecular diagnosis of plant infestation

BACKGROUND Anoplophora chinensis (Forster) (Coleoptera Cerambycidae) is a polyphagous long-horned beetle native to Eastern Asia that infests a wide range of broadleaved plants, causing disruption of vascular tissue, structural weakness and tree death. As a result, A. chinensis is a quarantine pest for the European Union. In order to confirm its infestations on plants, it is necessary to obtain adult or larval specimens on which morphological or molecular analysis can be performed. However, obtaining such specimens from infested plants can be a demanding and difficult task. Therefore, a diagnostic tool that is non-invasive for the plant and able to be performed in the absence of any insect stages may be useful to confirm infestations of A. chinensis on plants. RESULTS A protocol is presented that is based on polymerase chain reaction amplification using DNA extracted from A. chinensis faecal material collected in the field. CONCLUSION Results obtained in the present work show that the non-invasive approach is a reliable and accurate alternative diagnostic tool in phytosanitary surveys.

Feeding and oviposition of Anoplophora chinensis on ornamental and forest trees

Studies were conducted on maturation feeding and oviposition of Anoplophora chinensis (Forster) (Coleoptera: Cerambycidae), a recently introduced quarantine pest in Europe on different plant species of great importance for urban and forest environments in Italy. The tested plant species were Aesculus hippocastanum, Acer negundo, A. campestris, Castanea sativa, Corylus avellana, Platanus x acerifolia, Quercus petrea, Q. pubescens, Q. rubra, Tilia platyphyllos, Ulmus minor and U. pumila. Tested adults of A. chinensis originated from a population of a recently infested site in Italy (Rome) and all experiments were conducted in a walk-in insect cage under quarantine conditions. Adults of A. chinensis showed a maturation feeding preference for twigs of Acer species (A. negundo and A. campestris) and for C. avellana. In the oviposition experiments conducted on bolts of tested plant species, A. chinensis females did not show clear preferences and some data did not reflect the preferences shown during the feeding experiments. Nevertheless, A. negundo and A. campestris were well accepted plant species for oviposition besides A. hippocastanum and T. platyphyllos.

Computer-aided photographic identification of Rosalia alpina (Coleoptera: Cerambycidae) applied to a mark-recapture study

Assessing the conservation status of protected species needs quantitative population data, generally obtained using Capture‐Mark‐Recapture methods (CMR). The exploitation of natural marking (e.g. individual morphological traits) offers an interesting alternative, based on image analyses, which may result in a less manipulation of protected species compared to the typical artificial marking method. In our 2‐year CMR study, we tested for the first time in the natural setting the feasibility and the application of the computer‐aided photographic identification method of Rosalia alpina using the individual elytral spots as the natural marking. The I3SC software was used for the photographic analysis. Data were collected from populations of two National Parks of central Italy during July–August in 2014 and 2015. We developed a standard procedure in order to optimise the image acquisition in the field and to acquire clear and comparable images, facilitating the I3SC screening process. The results demonstrated that the computer‐aided photographic identification of natural markings can be implemented in a CMR population study of R. alpina. Our image processing approach showed that using only the elytral central spot contours made the tracing contour process less time‐consuming obtaining reliable results. Furthermore, I3SC output scores were used to identify a threshold value for the identification of new individuals or recaptures, facilitating the final identification proposed by operators. Finally, we assessed the possibility of performing the methodology using a Citizen Science approach.

Hexamermis popilliae n. sp. (Nematoda: Mermithidae) parasitizing the Japanese beetle Popillia japonica Newman (Coleoptera: Scarabaeidae) in Italy

A new species of mermithid nematode, Hexamermis popilliae n. sp. (Nematoda: Mermithidae) is described from the Japanese beetle Popillia japonica Newman in Italy, an area of new introduction for this invasive pest. The combination of the following characters separates H. popilliae from other members of the genus Hexamermis Steiner, 1924: adult head obtuse; amphidial pouches slightly posterior to lateral head papillae in female but adjacent to lateral head papillae in males; amphidial openings large, well developed; amphidial pouches elliptical in females and oblong in males; cuticular vulvar cone well developed, vulvar lips greatly reduced or lacking, vagina curved at tip where meeting uteri, without reverse bend (not S-shaped), spicules slightly curved, with a slight bend in the basal portion, approximately equal to body width at cloaca. This is the first record of a species of Hexamermis parasitizing the Japanese beetle Popillia japonica. The only previous mention of mermithid nematodes from P. japonica was an undescribed species of Psammomermis in North America. Hexamermis popilliae will be evaluated as a potential biological control agent in an integrated control program of the Japanese beetle in Italy.

Graphosoma lineatum (Hemiptera: Pentatomidae): a suitable host for mass rearing Ooencyrtus telenomicida (Hymenoptera: Encyrtidae)

ABSTRACT The species Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae) is currently being considered as a candidate for augmentative biological control agent (BCA) against several pests, including Halyomorpha halys (Stål) (Heteroptera: Pentatomidae). Protocols for mass production of a BCA need fundamental information on its biological attributes. Here we tested a possible laboratory host for the rearing of O. telenomicida: the common bug Graphosoma lineatum L. (Heteroptera: Pentatomidae). At tested conditions, O. telenomicida biological parameters were: rm 0.154, offspring production 84.07 specimens/female, sex ratio (% females) 71%, juvenile development time about 16 days, population doubling time 4.52 days, emergence rate about 90%.

Entomopathogenic fungi and nematodes against larvae of the chestnut weevil, Curculio elephas (Coleoptera: Curculionidae): a laboratory evaluation

ABSTRACT Pest control in chestnut orchards is mainly achieved by chemicals, but there is growing focus on the potential use of biological control agents. The larval susceptibility of the chestnut weevil Curculio elephas L. (Coleoptera: Curculionidae) to different strains/species of entomopathogenic fungi and nematodes was evaluated in laboratory by soil cup bioassays. In the experiments with fungi, a wild strain of Metarhizium anisopliae caused the highest larval mortality (about 90%) compared with a commercial and a wild strain of Beauveria bassiana (80% and 77% respectively). Regarding nematodes, the commercial strain of Heterorhabditis bacteriophora was more effective in the control of chestnut larvae (77% insect mortality) than Steinernema carpocapsae (43%).

The sexuales of Cinara palaestinensis Hille Ris Lambers, the Aleppo pine aphid (Hemiptera: Aphididae Lachninae).

The male and the oviparous female of Cinara palaestinensis Hille Ris Lambers, the Aleppo pine aphid, are recorded for the first time, in populations on Pinus halepensis in Italy. Description and illustrations are provided together with additional notes on taxonomy, ecology and distribution of the species.