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The brown marmorated stink bug (BMSB), Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is an Asian invasive plant-feeding insect and an emerging kiwifruit pest. Knowledge about the BMSB dynamics and damage to kiwifruit outside the bug native range is scarce. This 2-yr study was aimed at describing phenology and infestation dynamics of BMSB in green-fleshed and yellow-fleshed kiwifruits. Natural enemies were investigated as well. Field surveys were performed weekly in two sites in Northern Italy by pheromone-baited traps and visual samplings, from early Spring to mid-Autumn. All BMSB life stages were collected and kept under observation to assess occurrence of parasitoids. A sample of fruit was dissected weekly to detect BMSB feeding injuries. In 2018–2019, BMSB was found throughout the growing season with two generations per year with a large overlapping of all life stages. Pheromone-baited traps and visual samplings gave consistent results and can be both considered effective sampling methods on kiwifruit. Fruit injuries were significantly related to kiwifruit development stage, weekly captures of BMSBs by traps, and cultivar. Several BMSB egg masses were found on kiwifruit leaves. Anastatus bifasciatus Geoffroy (Hymenoptera: Eupelmidae), a native egg parasitoid with Palearctic distribution, emerged from 20.14% of eggs in 2018, but the percent parasitism dropped to 0.47% in 2019. In both years, other natural enemies were found exerting negligible pressure on BMSB populations. The determination of reliable economic thresholds for BMSB on kiwifruit is urgently needed to develop a robust and sustainable integrated pest management (IPM) strategy, and this study provides data towards that direction.

Halyomorpha halys, (the brown marmorated stink bug, BMSB), is a high-concern invasive species causing severe damage to orchards in many countries outside its native Asian range. Control options matching both effectiveness and sustainability are currently lacking. Inhibitors of chitin biosynthesis might be exploited for integrated management programs because of the overall better ecotoxicological profile in comparison with most neurotoxic insecticides used so far against BMSB. In this study, the activity of triflumuron, a benzoylphenyl urea hampering chitin biosynthesis, was tested on BMSB in laboratory and field conditions. In laboratory bioassays, the insecticide was sprayed on potted peach plants (30 cm high) and residues were aged in a glasshouse for 0, 7, 14, and 21 d. Then, third-instar bugs were placed on the plants and continuously exposed to residues. Mortality was scored after 7, 14, and 21 d exposure. Triflumuron caused significantly higher mortality on BMSB nymphs in comparison with water controls at all aging periods. Moreover, aging of residues up to 21 d did not cause any significant reduction of activity. Field experiments were also carried out in 2019 in eight pear orchards. Injuries to fruits at harvest were compared between plots where triflumuron was added to insecticide sprays against BMSB and control plots managed exactly in the same way but without any triflumuron treatment. An overall mean of 9.99 ± 1.98% stink bug injured fruits was detected in plots managed with the strategy including triflumuron, whereas 19.45 ± 3.55% of fruits were injured in plots assigned to controls.

The codling moth Cydia pomonella (L.) (Lepidoptera: Tortricidae) is one of the key pests of pome fruit and walnut in almost all growing regions of the world and has developed resistance to several insecticides. In this study, the susceptibilities of 15 codling moth populations to emamectin benzoate and 9 populations to lambda cyhalothrin collected in five European countries were measured by standard diet incorporation bioassays. Variation in susceptibility was observed among populations, with LC50 values ranging from 0.0017 to 0.0119 mg a.i./kg diet for emamectin benzoate and from 0.033 to 0.292 mg a.i./kg diet for lambda cyhalothrin. Our results revealed only small variations in emamectin benzoate susceptibility between populations, indicating no selection of resistance to this active ingredient. Even though a wider range of responses was detected for lambda cyhalothrin, our results also suggest that populations remain susceptible to this insecticide. Based on pooled LC95 evaluations, we propose the use of concentrations 0.02 mg a.i./kg of diet for emamectin benzoate and 0.60 mg a.i./kg of diet for lambda cyhalothrin in order to discriminate between resistant and susceptible individuals.

The Thematic Group “Plant Health” (TG-PH) of DISTAL, established as part of the “Departments of Excellence” project, has been active since October 2020. To date, 13 research groups with over 40 people including teaching staff, researchers, technicians, postdocs and doctoral students have joined the TG-PH. The common goal of the TG’s activities is to protect and enhance the role of “Plant Health” with a plurality of approaches and specific activities which include: (i) the development of strategies to prevent, monitor and control plant pests; (ii) new agronomic practices and plant nutrition approaches to reduce the impact on ecosystems; (iii) the selection and characterization of new varieties more resilient to biotic/abiotic stresses; (iv) the implementation of sustainable agricultural and food policies. Most of these activities are consistent with initiatives to effectively address major global policy issues such as reducing the use of pesticides and fertilizers, increasing biodiversity in order to ensure healthy, affordable and sustainable food supply to society compliant with food quality and safety. The high interdisciplinarity of the TG-PH is ensured by the wide range of scientific sectors to which the research groups involved belong. The common commitment is to pursue the sustainability objectives of the European Green Deal by bridging the gap between research and practice, accelerating the process of transferring research results and following up with networking. Moreover, TG-PH members share the common belief that only a stronger synergy between this knowledge and expertise coupled with a strong public-private partnership (PPP) will allow for the translation of the results of basic research into concrete solutions useful for the various stakeholders and society at large.

Several elicitors, stimulating induced resistance mechanisms, have potential in preventing or mitigating pathogen infections. Some of these compounds, triggering the production of jasmonic acid (JA), a precursor of herbivore-induced plant volatiles, could also play a central role in indirect resistance to pest species, by improving beneficial arthropod performance, and necrotrophic pathogens. In the current work,Trichoderma gamsii/T. asperellumand silica gel treatments – alone and in combination – were studied to evaluate the plant defence mechanism on grapevines (Vitis viniferaL.) by laboratory and field trials. JA production level was measured before and afterPlasmopara viticolainfection on potted vines. JA production induced by silica gel was higher than that caused byTrichodermabefore infection. InTrichoderma-treated plants, JA production increased afterP. viticolainoculation. In vineyard field trials, Mymaridae (Hymenoptera: Chalcidoidea) showed higher captures in transparent sticky traps on silica gel-treated plants, in comparison with control. On the other hand, no significant attraction was detected for Ichneumonoidea and other Chalcidoidea in silica gel andT. gamsii/T. asperellum-treated plants. The potential effects of elicitors are discussed, in the frame of attract and reward strategy.

Environmental impacts of genetically modified crops are mandatorily assessed during their premarket phase. One of the areas of concern is the possible impact on nontarget organisms. Crops expressing Cry toxins might affect Lepidoptera larvae living outside cultivated fields, through pollen deposition on wild plants, which constitute their food source. While pollen toxicity varies among different events, possible exposure of nontarget species depends on the agro-environmental conditions. This study was conducted in two protected areas in Italy, characterized by different climatic conditions, where many Lepidoptera species thrive in proximity to maize cultivations. To estimate the possible exposure in absence of the actual stressor (e.g., Cry1-expressing maize plants), we conducted a two-year field survey of butterflies and weeds. Indicator species were selected-Aglais (Inachis) io in the Northern site and Vanessa cardui in the Southern site-and their phenology was investigated. Pollen dispersal from maize fields was measured by collection in Petri dishes. Duration and frequency of exposure was defined by the overlap between pollen emission and presence of larvae on host plants. Different risk scenarios are expected in the two regions: highest exposure is foreseen for A. io in the Northern site, while minimal exposure is estimated for V. cardui in the Southern site. In the latter case, locally grown maize cultivars flower in mid-summer in coincidence with an aestivation period for several butterfly species due to hot and dry conditions. Moreover, host plants of V. cardui are at the end of their life cycle thus limiting food availability.

We studied the impact that two agro-ecological service crops or ASC, (vetch and barley), and two different ASC termination techniques (using a roller crimper or green manure) had on predation pressure in an organic vegetable system. We compared these two ASC termination techniques with a biodegradable plastic mulch, commonly used to control weeds in vegetable organic systems, over two consecutive growing seasons (2014–2015). Predation pressure was evaluated by means of artificial caterpillars made of green plasticine. Attack marks left on them were assigned to predators including chewing insects, birds and mammals. The frequencies of attack were significantly correlated with the activity density of carabids. In both experiments, carabid activity density was higher in ASC terminations than in the biodegradable plastic mulch control. Predation rate was significantly higher in the field with vetch flattened by roller crimper, while no significant difference was detected between termination techniques or in comparison with the control when barley was used as an ASC. The rate of ASC decomposition was higher in vetch than in barley and this could be the reason for the higher activity density of springtails in vetch. Carabid activity density was also positively correlated with springtail abundance. In conclusion, our field experiments showed that artificial caterpillars could represent a good standardized method to assess predation pressure in different habitats.

The effect of fungicides on the entomopathogenic fungus Beauveria bassiana strain ATCC 74040 (Naturalis®) was evaluated in vitro and in vivo. The formulated fungicides Cantus® (boscalid), Frupica (mepanipyrim), Galben (benalaxyl), Melody® Compact (iprovalicarb + Cu oxychloride), Oracle™ (fenamidone + Cu), Prosper® 300 CS (spiroxamine), Signum® (boscalid + pyraclostrobin), Switch® (cyprodinil + fludioxonil) and Talendo® (proquinazid) were tested on fungal colony growth from 10 field dose (10FD) to 10−4 FD. Each product mixed with Naturalis at FD was also tested against Trialeurodes vaporariorum on zucchini plants. Fungal colony growth was not affected by Cantus, Galben, Melody Compact, Oracle and Talendo at FD, while Frupica and Prosper 300 CS reduced colony growth by 9.7% and 6.9%, respectively. All these products did not inhibit the activity of B. bassiana on whiteflies at FD. On the contrary, Signum and Switch significantly inhibited colony growth at all doses and reduced the entomopathogenic activity on whiteflies when applied in mixture with B. bassiana. The toxic effect of both fungicides on B. bassiana persisted for 10 days after treatments, with a 91.2% reduction in nymph mortality in comparison to control for Signum and 87.4% for Switch. The mode of action of their active ingredients, boscalid, pyraclostrobin, cyprodinil and fludioxonil, individually and in mixture (boscalid + pyraclostrobin and cyprodinil + fludioxonil), was studied on fungal colony growth, spore germination, germ tube elongation and spore survival from 10FD to 10−2 FD. All these parameters were reduced by the four active ingredients at all doses, pyraclostrobin and fludioxonil completely inhibited spore germination, fludioxonil alone and in mixture with cyprodinil also inhibited completely spore survival.

Agro-ecological service crops (ASC) can increase the vegetation complexity of agroecosystems leading to a positive impact on natural enemies of arthropod pests and on weed control. In this study, two ASC terminations (green manure and roller crimper) and a Mater-Bi-mulched control (MB) were compared in order to describe the effects on pests and beneficial dynamics in an organic vegetable system. The trials were conducted over two consecutive growing seasons in 2014 and 2015. Zucchini were grown as cash crop and barley as ASC. Pests and natural enemies were monitored fortnightly by visual samplings along the whole zucchini-growing season. Zucchini plants showed a faster vegetative growth in MB treatment than in ASC terminations. In both years, MB plots were characterized by higher soil temperature and higher leaf nitrogen concentration resulting in plants more susceptible to Aphis gossypii infestations. In all the experimental plots, natural enemies controlled aphid infestations and no insecticide and sprays were necessary. In conclusion, the tested ASC techniques have been suggested as a tool to mitigate aphid infestation.

The Harlequin ladybird Harmonia axyridis Pallas, native to eastern Asia, is an invasive, non-native species that has recently achieved an almost worldwide distribution. A conspicuous feature of this species is colour polymorphism of the elytra. In its native area, the populations consist of a recessive non-melanic morph, several dominant melanic morphs and small numbers of other (rare) morphs. The morph proportions in native populations have been intensively studied and vary with geographic area, climate and time. In contrast, colour polymorphism in invaded regions has been little studied. We examine and try to account for the morph frequencies observed across the different invaded regions. In America, monomorphic populations consist of the non-melanic morphs while European populations contain also melanic morphs. In particular geographic areas of Europe, the average percentage of the non-melanic morphs varied between 78 and 99%. It was highest in the lowlands of northern Italy and central and northern Europe and decreased in the Alps and western (Spain, UK) and eastern (southeast Russia) margins of the recently invaded area. In central Europe the frequency of the non-melanic morphs decreased over the course of the year but increased over the years from 2010 to 2018. The local differences might thus arise through gradual change of the morph composition of the founder invasive, non-native population. However, the variation in non-melanic morph frequency was not correlated with climatic characteristics that might affect coccinellid polymorphism. The observed rate of change in morph proportions in our data was too small to explain the diversification of what was supposedly a uniform invasive, non-native population at the point of introduction.

The European corn borer (ECB), Ostrinia nubilalis Hubner (Lepidoptera: Crambidae), is a key pest of maize (Zea mays L.). In Northern Italy, larvae of the 2nd generation may damage cobs and kernels and the feeding activity can promote the proliferation of aflatoxigenic fungi, such as Aspergillus flavus, the major producer of aflatoxin B1 (AFB1). During 2017–2018, the efficacy of two strategies to control ECB in maize was assessed. Biological control strategy (Trichogramma brassicae Bezdenko and Bacillus thuringiensis Berliner), conventional chemical strategy (chlorantraniliprole) and an untreated control were compared to assess: i) the effect of the strategies on ECB infestation; ii) the association of ECB and AFB1 kernels contamination; iii) the impact of the strategies on beneficial arthropods. The conventional chemical strategy demonstrated the best control of ECB infestation, followed by biological control strategy and the untreated control. No significant differences in maize yield were found among strategies. The role of ECB on AFB1 concentration was demonstrated only in 2017, when higher level of infestations occurred simultaneously with an extended period of drought and high temperatures, sanctioning the important role of meteorological conditions on AFB1 contamination. The activity density of ground beetles, rove beetles and spiders and the mean number per leaf of the most abundant beneficial insects dwelling on plants (coccinellids, predatory thrips and lacewings) did not show significant changes between pre-and post-treatment with chlorantraniliprole, highlighting the selectivity of this pesticide in the short time. This study provides some contribution for the reduction of non-renewable input in Italian maize fields, demonstrating that biological control strategy, although less effective than conventional chemical control, can be a feasible approach to control ECB second larval generation, without any increment of AFB1 level in grains and yield loss.

The spread of the multicolored Asian lady beetle Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) in Europe coincided with the decline of the native Adalia bipunctata (L.) (Coleoptera: Coccinellidae). Both species are predators of aphids in orchards, and differential susceptibility to insecticides used to control fruit pests may contribute to explain the competitive advantage of the invasive over the native species. In this study, the insecticidal activity of imidacloprid and spinetoram was tested on third instars and adults of both ladybird species under laboratory conditions. Insects were exposed to insecticide residues on potted peach plants that were sprayed with the maximum recommended field doses (100 mg/liter for imidacloprid and 66.67 mg/liter for spinetoram). Mortality was scored after short (2 d for both stages) and long (7 and 10 d for adults and larvae, respectively) exposure periods. The susceptibility to the insecticides was very similar for H. axyridis and A. bipunctata. Imidacloprid caused a significant increase in the mortality of both stages of the two species for every exposure period. On the other hand, when exposed to spinetoram residues, larvae and adults of both ladybirds did not show higher mortality than controls after short and long exposure periods. The pest suppression provided by ladybirds, which could be severely hampered by the applications of nonselective pesticides, might be enhanced by the adoption of reduced-risk insecticides, selective for these beneficial insects.

Since the mid-2000s, the exotic coccinellid species Harmonia axyridis (Pallas) has established itself in Northern Italy, raising serious concerns about possible repercussions on native ladybirds. In this study we compared the ladybird assemblages in 2015–2016 with those sampled in 1995–1996, before the arrival of H. axyridis. Surveys were carried out in the same sites and with the same methods for both periods. Aphidophagous ladybirds were sampled in hedgerows and herbaceous habitats at field margins by mechanical knockdown and sweeping net, respectively. The changes in the structure of ladybird communities after the arrival of H. axyridis were significantly different between arboreal and herbaceous habitats. Harmonia axyridis is currently the dominant species in shrubs and trees, and all the native ladybird species taken together account for only approximately one third of the total individuals sampled in 2015–2016. On the other hand, the relative abundance of the exotic species in herbaceous habitats was low, and it has had a negligible relevance on the structure of ladybird communities on grasslands. Among native species, Adalia bipunctata (L.), whose ecological niche largely overlaps with that of H. axyridis, suffered the largest decline between 1995–1996 and 2015–2016. The co-occurrence of H. axyridis invasion and the regression of A. bipunctata suggest a direct impact of the exotic species, because no other major modifications occurred in the studied areas between sampling periods.

Landscape structure as well as local vegetation influence biodiversity in agroecosystems. A study was performed to evaluate the effect of floristic diversity, vegetation patterns, and landscape structural connectivity on butterflies (Lepidoptera: Papilionoidea and Hesperiidae), carabids (Coleoptera: Carabidae), syrphids (Diptera: Syrphidae), and sawflies (Hymenoptera: Symphyta). Vegetation analysis and insect samplings were carried out in nine sites within an intensively farmed landscape in northern Italy. Plant species richness and the percentage of tree, shrub, and herb cover were determined by means of the phytosociological method of Braun-Blanquet. Landscape structural connectivity was measured as the total length of hedgerow network (LHN) in a radius of 500 m around the center of each sampling transect. Butterflies species richness and abundance were positively associated both to herb cover and to plant species richness, but responded negatively to tree and shrub cover. Shrub cover was strictly correlated to both species richness and activity density of carabids. The species richness of syrphids was positively influenced by herb cover and plant richness, whereas their abundance was dependent on ligneous vegetation and LHN. Rarefaction analysis revealed that sawfly sampling was not robust and no relationship could be drawn with either vegetation parameters or structural connectivity. The specific responses of each insect group to the environmental factors should be considered in order to refine and optimize landscape management interventions targeting specific conservation endpoints.

Conventional insecticide assays, which measure the effects of insecticide exposure on short-term mortality, overlook important traits, including persistence of toxicity or sub-lethal effects. Therefore, such approaches are especially inadequate for prediction of the overall impact of insecticides on beneficial arthropods. In this study, the side effects of four modern insecticides (chlorantraniliprole, emamectin benzoate, spinosad, and spirotetramat) on Adalia bipunctata (L.) (Coleoptera: Coccinellidae) were evaluated under laboratory conditions by exposition on treated potted plants. In addition to investigation of acute toxicity and persistence of harmful activity in both larvae and adults of A. bipunctata, demographic parameters were evaluated, to provide a comprehensive picture of the nontarget effects of these products. Field doses of the four insecticides caused detrimental effects to A. bipunctata; but in different ways. Overall, spinosad showed the best toxicological profile among the products tested. Emamectin benzoate could be considered a low-risk insecticide, but had high persistence. Chlorantraniliprole exhibited lethal effects on early instar larvae and adults, along with a long-lasting activity, instead spirotetramat showed a low impact on larval and adult mortality and can be considered a short-lived insecticide. However, demographic analysis demonstrated that chlorantraniliprole and spirotetramat caused sub-lethal effects. Our findings highlight that sole assessment of mortality can lead to underestimation of the full impact of pesticides on nontarget insects. Demographic analysis was demonstrated to be a sensitive method for detection of the sub-lethal effects of insecticides on A. bipunctata, and this approach should be considered for evaluation of insecticide selectivity.

The potato tuberworm (PTW) Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) is key pest of potato in tropical and subtropical regions. From 2002 onward, PTW has emerged as a problem in the Bologna province, the main potato production area in Northern Italy. Field investigations were performed to study the temporal and spatial dynamics of PTW. Adult moths were monitored using pheromone-baited traps over 3 years (2009–2011). Traps were georeferenced and catches were analyzed by geostatistical maps. Each year, the percentage of damaged tubers at harvest was assessed. Pheromone trapping, integrated with temperature-dependent developmental times, showed that PTW completed two generations throughout the potato-growing season; the remaining generations developed in the noncrop season. Maps showed a clumped distribution of PTW at the landscape scale. The hot spots of infestation corresponded to the areas most intensively cropped with potato. Trap catches from hilling to harvesting were linearly and positively correlated with the percentage of damage in 2 out of 3 years and in the pooled data set. The present study demonstrated the widening of PTW areal to Northern Italy. In this area, georeferenced pheromone traps were validated as a useful monitoring technique for describing the phenology and distribution of PTW, thus providing crucial knowledge for the rational management of this pest.

Spinetoram is a fermentation insecticide, derived from the actinomycete Saccharopolyspora spinosa. It works by disrupting the GABA-gated chloride channels and by causing persistent activation of insect nicotinic acetylcholine receptors. This study aimed to evaluate the efficacy of spinetoram for control of neonate larvae of both oriental fruit moth (OFM) Grapholita molesta (Busck) and codling moth (CM) Cydia pomonella (L.) in semi-field and laboratory trials. OFM and CM neonate larvae responded similarly to spinetoram, which showed high efficacy on both species. In semi-field experiments, regression analysis of the percentage of damaged fruits as a function of days after treatment showed a better performance of the highest spinetoram dose (10 g a.i./hl) in comparison with the maximum recommended field dose of the reference product emamectin benzoate (2.85 g a.i./hl). Surface-treated diet assays revealed LC50 values of 6.59 and 8.44 ng a.i./cm2 for neonate larvae of OFM and CM larvae, respectively. High percentages of mortality were recorded on both species after 24-h exposure to treated diet. For these reasons spinetoram could be considered a valuable tool in IPM strategies for OFM and CM control.

Relationships of nine Italian Chrysotoxum species were analysed using morphological and molecular data. The morphology-derived cladogram revealed three well-defined groups: (i) C. cautum, (ii) the arcuatum group (C. arcuatum, C. fasciola- tum) and (iii) the festivum group (C. festivum - C. vernale, C. bicinctum, C. elegans, C. octomaculatum and C. parmense). Trees inferred from COI-tRNALeu-COII sequences were largely in agreement, but they identified (i) C. parmense as an isolated branch, (ii) C. festivum and C. vernale as separate entities, (iii) C. elegans within a paraphyletic C. festivum clade. ITS2 trees were partially unresolved but C. parmense sequence emerged as a sister to the festivum group. The monophyly of the festivum group derived from morphological data was rejected by a phylogenetic test performed on combined molecular data set. The diagnostic value of some morphological characters commonly used to identify Chrysotoxum species is therefore questioned.

Le tematiche che coinvolgono lo sviluppo ed applicazione delle agrobiotecnologie ed in particolare l’argomento “Organismi Geneticamente Modificati”, sia per la loro rilevanza ed attualità scientifica, sia per i molteplici e delicati aspetti di natura sociale ed economica coinvolti, suscitano da sempre grande interesse. Sempre più spesso, in particolare sull’argomento OGM, si assiste da parte di addetti ai lavori o di rappresentanti della società civile, a prese di posizione a favore o contro l’uso ed il rilascio di specie geneticamente modificate o loro derivati, la stragrande maggioranza delle volte non suffragate da dati oggettivi e scientificamente validati e condivisi. In un tale contesto è facile immaginare quali e quante implicazioni, le cui conseguenze possono essere difficilmente prevedibili, possano derivare da affermazioni e valutazioni frettolose in materia. E’ per questo motivo che chi si occupa di attività di Ricerca in questo settore, e più in generale di Biosicurezza, ha l’obbligo, scientifico ed etico, di valutare con particolare attenzione i risultati delle proprie ricerche e comunque ogni aspetto, tecnico e non tecnico, che esse coinvolgono. Ciò assume ancora maggiore rilevanza in una realtà come quella del nostro Paese, ove la salvaguardia della biodiversità e la protezione della qualità delle produzioni agroalimentari del Made in Italy rappresentano due valori non discutibili. C’è poi da considerare che, se anche un cambiamento viene definito tecnicamente attuabile ed abbia passato gli esami più rigidi e stringenti in materia di “analisi del rischio”, a volte non risulta comunque accettabile dalla società civile, in special modo se essa stessa non è stata partecipe del processo che lo ha generato. Il Progetto MAN-GMP-ITA, che vede impegnati il CRA, l’ISPRA, l’Università di Bologna, il Consorzio In.Bio, oltre l’ENEA, ha l’obiettivo di valutare il rischio dell’esposizione a Piante OGM in aree protette e sensibili in diversi areali del nostro Paese. La ricerca non utilizza piante geneticamente modificate per la sperimentazione in campo. L’obiettivo, infatti, è assumere informazioni dettagliate dei livelli preesistenti di biodiversità nelle aree da proteggere per poter poi fissare con precisione gli obiettivi di protezione ambientale ed elaborare e proporre una metodologia per monitorare e gestire i possibili effetti sulla biodiversità. Il presente manuale “Il campionamento dell’artropodofauna per il monitoraggio ambientale” rappresenta un deliverable del Progetto e nel contempo contribuisce a fornire alla comunità scientifica uno strumento sviluppato secondo regole e metodologie in linea con gli attuali canoni scientifici condivisi ed applicabili ad analisi ecologiche dell’artropodofauna anche in ambiti diversi. Oltre che come strumento tecnico destinato agli operatori del settore, il manuale è pensato anche per consentire di approfondire tali tematiche a quanti lo desiderino, per studio, per professione o anche solo per formarsi una personale opinione sull’argomento.

La biodiversità agricola nella strategia nazionale per la biodiversità

As part of the LIFE+ MAN-GMP-ITA project concerning validation of risk management tools for GM plants in protected areas, two years of field trials were carried out in a maize-cropped area within the SCI-SPA Biotopes and environmental restoration areas of Bentivoglio, San Pietro in Casale, Malalbergo e Baricella in Northern Italy. A first array of experiments was aimed to quantify the drift of maize pollen in the receiving environment. By means of Petri dishes covered with gelatin we confirmed the findings that most maize pollen falls very close to the crop edge. Collections by leaf-print technique were carried out on nettles (Urtica dioica) wild growing in maize field margins to evaluate the actual amount of pollen deposited and retained by nettle leaves. Three samplings were performed in the same fields at 80% maize flowering, at 100% maize flowering and at the end of anthesis. Nettles were at a mean distance of 6.2 m from maize and the maximum mean pollen density (2.1 grains cm-2) was observed in the first sample. Moreover, we checked the phenology of the second brood of peacock butterfly (Inachis io) in nettles growing in margins of maize field. Larval colonies were detected both in 2011 and 2012 and a complete temporal overlap with maize flowering was observed. The distribution of larvae was clumped with most nettles having no caterpillars and few plants being highly infested.

Field experiments were carried out in 2000 and 2001 in northern Italy, with the aim of developing a composite sampling strategy for estimating populations of Liriomyza huidobrensis (Blanchard) larvae and mines on lettuce. Larval parasitoid populations also were sampled to estimate the contribution of these beneficials to pest control. Covariance analysis and parallelism test indicated that there were not significant differences in the coefficient of Taylor’s power law between treatments (untreated versus treated) and between seasons (2000 versus 2001) for both pest and parasitoid stages. The slope of each regression was significantly >1 for L. huidobrensis mines and larvae, and endoparasitoid and ectoparasitoid larvae, indicating a clumped distribution of both pest and parasitoids. Constant precision level stoplines for mines and larvae of L. huidobrensis and for endoparasitoid and ectoparasitoid larvae were calculated, by using the common a and b derived from Taylor’s power law. Wilson and Room binomial sampling was used to estimate the mean number of L. huidobrensis mines or live larvae from the ratio of leaves with mines. In this way, it is possible to estimate the mean density of L. huidobrensis by counting the leaves with mines, an index parameter easy to obtain in field sampling. Validation of the presence-absence sampling plan by using field data collected in 2002 and 2003 seasons, showed that the Wilson and Room model fits very well empirical data. Statistical analysis does not show any significant difference between observed and predicted data.

Il lavoro presenta i risultati di un monitoraggio per la tignola della patata nella provincia di Bologna. Nel lavoro viene dimostrata una relazione significativa tra le catture con trappole a feromoni e la percentuale di tuberi danneggiati.

In summer 2008, larvae, pupae and adults of Harmonia axyridis (Pallas) (Coleoptera Coccinellidae) were found in several localities in northern Italy. Since the first record in Turin (Piedmont) in 2006, this ladybird, just two years later, was collected up to the northeast of Italy. The colour forms found consisted for 97.52% of H. axyridis succinea and 2.48% of H. axyridis spectabilis (n = 1049). These records may represent a case study in modelling intra-guild predation and the spread of an exotic species.

Nucleopolyhedroviruses (NPV) are considered among the most promising microbiological control agents for Spodoptera littoralis (Boisduval) (Lepidoptera Noctuidae). In a first laboratory experiment, a new SlNPV-based formulation was compared with a conventional Bt toxin product in order to evaluate its potential role as bioinsecticide for the short-term control of S. littoralis. Both formulations were tested on second instar larvae at the recommended dosages for treatment of vegetable crops. Four days after the treatments, Bt toxins caused higher mortality and significantly reduced leaf damages; on the contrary no significant differences were recorded between SlNPV and control treatments. Further investigations were carried out to assess the impact of SlNPV on S. littoralis over time. The mean lethal time (LT50) for second instar larvae treated with SlNPV was 7.32 days and it was significantly shorter than LT50 in control group.

La scelta di cultivar di patata a maturazione precoce e l'attuazione delle giuste pratiche colturali possono fare molto per prevenire i danni da tignola. La data di raccolta è risultata essere il fattore di contenimento più importante.

The pea leafminer, Liriomyza huidobrensis (Blanchard) (Diptera: Agromyzidae), is a serious insect pest infesting open field lettuce plantings in northern Italy. In these cropping systems, it coexists with several other agromyzid species that have negligible economic importance on open field vegetables. The rapid detection of L. huidobrensis is crucial for effective management strategies, but the identification of agromyzids to species can be very difficult at adult as well at immature stages. In this study, a polymerase chain reaction (PCR)-restriction fragment length polymorphism assay is proposed to separate L. huidobrensis from Liriomyza bryoniae (Kaltenbach), Liriomyza trifolii (Burgess), and Chromatomyia horticola (Goureau), which usually occur in the same lettuce plantings. An approximately 1,031-bp region of the mitochondrial genome encompassing the 3' region of cytochrome oxidase I, the whole leucine tRNA, and all of the cytochrome oxidase II was amplified by PCR and digested using the enzymes PvuII and SnaBI separately. Both endonucleases cut the amplicons of L. huidobrensis in two fragments, whereas the original band was not cleaved in the other analyzed species. The presence of Dacnusa spp. DNA does not bias the assay, because the PCR conditions and the primer set here described do not amplify any tract of this endoparasitic wasp genome.

In order to optimize resources, an assay allowing the detection of several etiological agents would be useful. This paper describes a polymerase chain reaction (PCR)-based assay for the parallel detection of different pathogens in mosquitoes (Diptera: Culicidae). The assay combines the analysis of both RNA and DNA, hence allowing the detection of both flaviviruses (Flaviviridae: Flavivirus) and filarial nematodes (Spirurida: Onchocercidae). The sensitivity of diagnostic assay for both flavivirus and nematode infections was tested by means of spiked samples and resulted adequate for the purpose of screening mosquito samples. The assay was implemented to check pathogen infections in 637 mosquitoes field-collected in Romagna, northern Italy. The integrity of RNA extracted from mosquito pools was checked by control amplifications targeting the 18 S rRNA of mosquitoes. Control amplifications were successful in 118 out of 119 pools. Flavivirus RNA was not found in any of these 118 pools, whereas DNA of Dirofilaria immitis (Leidy) was detected in one pool of Aedes albopictus (Skuse).

Lepidoptera are the phytophagous group most at risk of impact by insect-resistant genetically modified (GM) plants since most of these crops have been developed to express toxins to specifically target lepidopteran pests. In the case of Bt-maize cultivation, pollen grains released by GM plants could dust larval host plants growing inside or nearby maize fields, thus leading to the exposure of caterpillars to the Cry toxins. This way of exposure has been studied mainly for butterflies, whereas moths, in spite of their great diversity and abundance, were rarely considered. To evaluate the potential exposure of moth species to maize pollen in absence of Cry-expressing plants, macro-moths were sampled by means of light traps in three protected areas of Northern, Central and Southern Italy where conventional maize is among the main crops. Light traps were activated in two consecutive years (2010- 11) from the beginning of June to the end of July, a period that encompasses the anthesis of most maize cultivars grown in Italy. Overall, 11446 individuals belonging to 201 species and nine families were collected. Given that larvae of several sampled species are likely to match the criteria of potential exposure to maize pollen and susceptibility to Cry toxins, macro-moths might be considered among the potential assessment endpoints for environmental risk assessment of GM plants, especially in the vicinity of protected areas.

The insecticidal activity of essential oils (EOs) on mosquito larvae has gained quite a lot of interest in recent scientific literature, and many articles envisage EOs as promising alternatives to conventional larvicides. However, the EOs described so far are not comparable in terms of efficacy with chemical or microbial larvicides. Moreover, for most EOs the low mammalian toxicity and the lack of environmental impacts have been claimed rather than tested. In industrialized countries, the availability of effective and environmental friendly microbial larvicides, will likely limit the EO-based products to very small market niches. Only in developing countries, where most aromatic plants are native, the full potential of botanical larvicides may be fully exploited. However, several research gaps remain to be filled before EOs could be considered as substitutes of conventional products.

Environmental impacts of genetically modified crops are mandatorily assessed during their premarket phase. One of the areas of concern is the possible impact on nontarget organisms. Crops expressing Cry toxins might affect Lepidoptera larvae living outside cultivated fields, through pollen deposition on wild plants, which constitute their food source. While pollen toxicity varies among different events, possible exposure of nontarget species depends on the agro-environmental conditions. This study was conducted in two protected areas in Italy, characterized by different climatic conditions, where many Lepidoptera species thrive in proximity to maize cultivations. To estimate the possible exposure in absence of the actual stressor (e.g., Cry1-expressing maize plants), we conducted a two-year field survey of butterflies and weeds. Indicator species were selected—Aglais (Inachis) io in the Northern site and Vanessa cardui in the Southern site—and their phenology was investigated. Pollen dispersal from maize fields was measured by collection in Petri dishes. Duration and frequency of exposure was defined by the overlap between pollen emission and presence of larvae on host plants. Different risk scenarios are expected in the two regions: highest exposure is foreseen for A. io in the Northern site, while minimal exposure is estimated for V. cardui in the Southern site. In the latter case, locally grown maize cultivars flower in mid-summer in coincidence with an aestivation period for several butterfly species due to hot and dry conditions. Moreover, host plants of V. cardui are at the end of their life cycle thus limiting food availability.