Investigations on Tuta absoluta (Lepidoptera: Gelechiidae): larval infestation on the tomato cultivated in open field and evaluation of five essential oils against larvae in laboratory

Abstract The tomato miner Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) is a Neotropical species, which cause serious damages to tomato in spread areas. It appeared in 2008 in Italy, where it seriously threatened tomato production both in greenhouse and open field cultivations. In this work a study on infestation by this leafminer on leaves was conducted in an organic cultivation of tomato (Lycopersicon esculentum Mill.) "Pizzutello" variety in Sicily (Italy), and the insecticidal activity of 5 essential oils (EOs) on T. absoluta was evaluated in laboratory. EOs of basil, cypress, laurel, peppermint and Spanish oregano were used against 3rd- and 4th-instar larvae to assess contact effects and, only for oregano and laurel, inhalation effects. Results showed that the infestation in field had a variable trend showing peaks in two periods, in the months of July and October. Larvae of T. absoluta developed on leaves for most of the growing season of tomato showing a peak of 1.5 larva per leaf in the first part of July decreasing in the subsequent months. Results on the use of essential oils against the leafminer showed a good larvicidal effects confirming their use as potential alternative for pest control. Basil, cypress and laurel oils showed major contact efficacy. Inhalation effects of the oils of oregano and laurel increased with increasing their doses with a positive correlation. Oregano oil was effective at lower doses than laurel

Distributed correlations and information flows within a hybrid multipartite quantum-classical system

Understanding the non-Markovian mechanisms underlying the revivals of quantum entanglement in the presence of classical environments is central in the theory of quantum information. Tentative interpretations have been given by either the role of the environment as a control device or the concept of hidden entanglement. We address this issue from an information-theoretic point of view. To this aim, we consider a paradigmatic tripartite system, already realized in the laboratory, made of two independent qubits and a random classical field locally interacting with one qubit alone. We study the dynamical relationship between the two-qubit entanglement and the genuine tripartite correlations of the overall system, finding that collapse and revivals of entanglement correspond, respectively, to raise and fall of the overall tripartite correlations. Interestingly, entanglement dark periods can enable plateaux of nonzero tripartite correlations. We then explain this behavior in terms of information flows among the different parties of the system. Besides showcasing the phenomenon of the freezing of overall correlations, our results provide new insights on the origin of retrieval of entanglement within a hybrid quantum-classical system.Comment: 9 pages, 5 figures. To appear on Phys. Rev.

Indagine su Henosepilachna elaterii (Rossi) (=Epilachna chrysomelina (F.)) e Raphidopalpa foveicollis (Lucas) in meloneti biologici della Sicilia occidentale.

Investigations on Henosepilachna elaterii (Rossi) and Raphidopalpa foveicollis (Lucas) in an organic cultivation of winter melon in western Sicily. A study on H. elaterii and R. Foveicollis, serious pests of winter melon, was conducted in two organic melon fields of the western Sicily. Dynamics of population and infestation levels were investigated. In addition, the possible influence of mulching on R. Foveicollis infestation has been taken into account. Our results showed that H. elaterii occurred only in one field from the beginning of June and it infested 60% of the plants in the mid-July, then the pest population density dropped to about 10%. R. foveicollis occurred in both locations from the beginning of June and reached high levels of population density around the mid-June; then the pest density rapidly decreased in the two following weeks. Adults were found in the traps and the peak catches occurred in mid-June. A greater number of catches was found in the traps placed between the rows and the greater number of individuals has been detected on plants of the not mulched plots. The percentage of plants with damaged leaves ranged from 68.7% to 100% on mulched plots and 93.3% to 100% on not mulched plots. In conclusion, the damages inflicted by R. foveicollis are counterbalanced by the rapid growing rate of the plant occurring during June. Hence, this pest may cause serious injuries only in case of heavy infestation on winter melon seedlings. Similarly, the damage caused by H. elaterii is usually not heavy even if presence of high levels of infestation

Studies on Reticulitermes lucifugus Rossi (Isoptera: Rhinotermitidae): a review of associated hindgut flagellates and investigations on protist species of the Sicilian subspecies, R. lucifugus \u201cSicily\u201d

The present study was conducted on protist species from R. lucifugus \u201cSicily\u201d subspecies in a field site of Palermo (Sicily, Italy) on June 2015. Since protist species associated with R. lucifugus in Europe are still confused and recent revisions are lacking, this work aims at achieving greater clarity on these symbiosis trough a review of the literature in light of new phylogenetic studies on this termite species. The purpose of this work was also to highlight and quantify protists associated with the Sicilian subspecies, R. l. \u201cSicily\u201d. Results pointed out the real protist community attributable to R. lucifugus from the literature and showed 13 protist species detected in the subspecies R. l. \u201cSicily\u201d. These species were consistent with previous reports except for Spironympha sp., mentioned for the first time from this termite. Total protist population estimates was 26,814.71 \ub1 1,121.92 protists per termite. Dinenympha exilis and D. gracilis were found in greater abundance with relative species abundance of 17%. Monocercomonas termitis, Microjoenia hexamitoides, Trichonympha minor and Pyrsonympha flagellata could be used to distinguish R. lucifugus because these protists are not found in other Reticulitermes species

Le infrastrutture ecologiche come elemento funzionale nella gestione della biodiversità degli agrosistemi, con particolare riferimento al vigneto

Molti studiosi, già da diverso tempo, hanno messo in risalto l’importanza della diversità vegetale negli agroecosistemi sull’aumento della presenza di artropodi utili che contribuiscono al contenimento delle specie dannose. In quest’ambito una strategia di difesa per mantenere alto il livello di biodiversità riguarda l’uso delle cosiddette “infrastrutture ecologiche” o “aree di compensazione ecologica”, cioè siepi o fasce di vegetazione adiacenti al campo coltivato o al suo che forniscono ospiti alternativi e siti rifugio per predatori e parassitoidi di insetti dannosi, aumentando in tal modo l’abbondanza dei nemici naturali e la colonizzazione delle colture confinanti. Alcuni lavori di campo hanno testato i concetti di ecologia del paesaggio applicata all’agricoltura, come ad esempio l’uso di corridoi biologici per contrastare insetti dannosi, evidenziando che l’uso di corridoi vegetazionali, interrompendo le monocolture, fungono da tramite per la dispersione di nemici naturali all’interno del campo, aumentando così il loro impatto sulle popolazioni dei fitofagi. La composizione delle specie costituenti la vegetazione circostante e la distanza alla quale i nemici naturali si disperdono nella coltura hanno grande influenza sull’abbondanza e diversità di insetti entomofagi all’interno di un campo. Risulta di rilevante importanza la gestione degli habitat, come forma di controllo della conservazione biologica allo scopo di creare adeguate infrastrutture ecologiche all’interno del paesaggio agrario, fornendo risorse di cibo, prede alternative e ripari ai nemici naturali. Nell’ambito del vigneto, l’incremento della diversità botanica ha apportato benefici soprattutto rilevabili nelle relazioni tra tignole e antagonisti, tra cicaline e i parassitoidi 4-2013 22 del genere Anagrus e tra acari e predatori quali acari Fitoseidi. È da tenere presente, però, che nonostante gli aspetti positivi delle infrastrutture ecologiche evidenziati, in alcune aree viticole possono verificarsi effetti sfavorevoli in relazione ad alcuni fitofagi quali cicaline, soprattutto quelle vettrici di fitoplasmi e virosi, cocciniglie e fillominatori. Vengono riportati i diversi studi finora effettuati in Italia e all’estero (paesi europei ed extra-europei).Ecological infrastructures as a functional element in the management of biodiversity of agroecosystems, with particular reference to the vineyard Many researchers have emphasized the importance of plant diversity in agro-ecosystems on increasing the presence of beneficial arthropods that contribute to the control of harmful species. In this context, a defense strategy to maintain a high level of biodiversity is the use of so-called “ecological infrastructure” or “ecological compensation areas”, i.e. hedges or strips of vegetation adjacent to the cultivated field or inside. These sites provide alternate hosts and refuge for predators and parasitoids of pests, thereby increasing the abundance of natural enemies and colonization of neighboring crops. Some field studies have tested the concepts of landscape ecology applied to agriculture, such as the use of biological corridors to control harmful insects that breaking monocultures, are the bridge to the dispersal of natural enemies in the field, increasing their impact on the pests populations. The different species of the surrounding vegetation and the distances that natural enemies disperse into the cropping system have a great influence on the abundance and diversity of beneficial insects. The habitat management is an aspect of conservation biological control using the appropriate ecological infrastructure in the agricultural landscape that provides resources for food, shelter and alternative prey to enhance natural enemies. In vineyards, the enhancement of botanical diversity has beneficial effects especially in the relationships between grape moths and antagonists, leafhoppers and parasitoids as Anagrus spp. and mites and predators as Phytoseiid mites. Despite the positive aspects of ecological infrastructures in the vineyard, unfavorable effects may occur in particular viticultural areas in relation to some pests such as leafhoppers, especially those vectors of grapevine phytoplasma and viruses diseases, scale and leafminers insects. In the paper we report the state of studies carried out in Italy, Europe and other world countries on the role of natural hedges and floral resources in supporting predatory insects with particular reference to Coccinellids and parasitoids of genus Anagrus and Trichogramma and associated natural enemies with tripids. In addition, we report briefly studies on the ecological effectiveness on species richness and abundance of animal groups and pollinators

Indagini sulla presenza di Prays oleae in oliveti a conduzione biologica della Sicilia occidentale

Investigations on presence of Prays oleae in organic olive orchards of western Sicily. This paper reports a study on the population dynamics of the olive moth, Prays oleae (Bern) (Lep., Plutellidae) in four organic olive orchards in western Sicily (Italy), from 2007 to 2010. The influence of the phytophagous on the fruit drop was detected. Also, the efficacy of treatments with Bacillus thuringiensis var. kurstaki on damage reduction was evaluated. Flight trend was monitored using delta-wing traps (3/ha) containing the sexual pheromone ((Z)-7-tetradecenal), placed in each olive orchard. Traps were hung in the inner zone of the canopy to a height of 1.50 m, and checked weekly from May to 2-3 days after the olive harvest. Capture data indicated that flight peaks occurred on June-July and September-October. In 2007, the population density of P. oleae moths was generally lower than the subsequent three years . The fruit infestation levels in all years were under 5% and a greater susceptibility of Biancolilla and Cerasuola var. than Nocellara var. were detected. In 2008, the fruit drop caused by P. oleae ranged from 12% to 47% in two orchards studied. Finally, the results for two years indicate that treatments with Bacillus thuringiensis (Bt) can significantly reduce the fruit fall caused by phytophagous in comparison with untreated olive orchards

Indagini sulle infestazioni di Aphis gossypii Glover su melone invernale (Cucumis melo Var. Helios) in aziende a conduzione biologica della Sicilia occidentale.

Investigations on the aphid infestation occurring on winter melon crops (Cucumis melo var. Helios) in organic farms of western Sicily The winter melon (Cucumis melo L.) is an important crop in Sicily. Previous studies carried out in western Sicily have shown that the aphid species Aphis gossipii is the key pest of winter melon crops.A. gossypii is a cosmopolitan species with very polyphagous habits; this phytophagous insect is capable of serious economic damage due to direct feeding of the sap plant and due to the honeydew secretion and the consequent presence of sooty mold and due to the possible transmission of viruses. The aim of this work was to investigate the levels of aphid infestation in two different organic winter melon fields located in western Sicily by monitoring the dynamic of population of A. gossypii and the complex of natural enemies associated with the pest. In addition the possible influence of mulching as aphid repellent has been evaluated. In one location we monitored the aphid infestation through direct observation of the plants that have been carried out weekly from transplant to harvest of the product. In the other location, we investigated the dynamics of population and levels of adult infestation, evaluating also the possible influence of mulching, using chromotropic traps, consisting in yellow adhesive plates placed horizontally in mulched rows, on the plastic film, and alleyways, on the ground. In addition, surveys were carried out by comparing mulched plots and not mulched plots. Our results showed that, in both locations, the population density of A. gossypii was low and no serious damage has been inflicted to the crop: this is probably related to the abundant presence of natural enemies of the pest and to the repellent action of mulching

Indagine su Raphidopalpa foveicollis (Lucas) nella coltura del melone biologico della Sicilia occidentale.

Investigations on Raphidopalpa foveicollis (Lucas) in an organic cultivation of winter melon in western Sicily Red pumpkin beetle (Raphidopalpa foveicollis), is a Chrysomelidae beetle that lives on various species of cucurbits with greater preference for Cucumis sp. Both larval and adult stages are injurious to the crops. The former feeds on roots and stems of the plants, while the latter feeds on foliage, petals and fruits. In Sicily, this insect has occurred in the past as a secondary pest on the winter melon, but sometimes it reaches levels of infestation to arouse considerable concern among farmers. In order to implement economic methods of pest control a study on organic cultivation of winter melon was conducted in Camporeale (500 meters a.s.l.) (Palermo). Particularly, the dynamics of population and infestation levels have been investigated, taking into account also the possible influence of mulching, using chromotropic traps. Such traps consisted of yellow adhesive plates placed horizontally in mulched rows, on the plastic film, and between the rows, on the ground. In addition, surveys were carried out by comparing mulched plots and not mulched ones. Results showed that the peak catches (47.4 adults / trap) occurred in mid-June and the greater number of catches was found in the traps placed between the rows, with significant difference. A greater number of individuals has been detected on plants of the not mulched plots than that of the mulched plots, even though no statistically significant difference was found. The percentage of plants with damaged leaves ranged from 68.7% to 100% on mulched plots and 93.3% to 100% on not mulched plots with no significant differences. The presence of adults has also been observed on fruits but without signs of trophic activity. In addition, young stages were not detected in the plants examined. In conclusion, the combined effect of mulching, at least until the vegetation does not cover the plastic film, and sticky traps, placed mostly between the rows, plays a synergistic action to the pest control. Considering the low cost of such technique, it may be a potential tool for managing this pest using mass trapping method

Dinamica di popolazione di Aphis gossypii possibile vettore del Virus della Tristeza in un agrumeto della Sicilia occidentale

Tra le specie di afidi che attaccano gli agrumi in Sicilia, Aphis spiraecola Patch, Toxoptera aurantii (B.d.F) e Aphis gossypii Glover rivestono importanza economica, essendo presenti dalla primavera all’autunno con livelli di infestazione molto alti. Oltre ai danni legati all’attività trofica, tutte e tre le specie primarie, sono in grado di trasmettere il virus della Tristeza (CTV); in bibliografia l’efficienza è considerata alta nel caso di A. gossypii e poco rilevante nel caso delle altre due specie. La trasmissibilità del CTV, oltre che dalla specie vettrice, dipende da diversi fattori quali, le specie di Citrus donatrici o recettrici, la virulenza dell'isolato del virus, il comportamento alimentare, riproduttivo e di diffusione del vettore. Nell’ambito del progetto “Lotta al virus della Tristeza sviluppo e innovazioni” finanziato dalla Regione Siciliana si è voluto monitorare la presenza A. gossypii e valutare i livelli di infestazione in un agrumeto a conduzione biologica sito nel territorio di Castelvetrano (TP) da maggio del 2012 fino a settembre 2013. Su 20 piante di arancio varietà Navel, scelte a caso su un appezzamento di circa un ettaro, per i quattro punti cardinali, è stata rilevata la percentuale di germogli infestati su una superficie di chioma di 0,25 mq. Inoltre, campioni di A. gossypii sono stati prelevati e sottoposti ad analisi per appurare la presenza del virus. Le osservazioni hanno mostrato che, in entrambi gli anni, l’infestazione di A. gossypii è iniziata alla fine di aprile, ha raggiunto i massimi livelli tra metà maggio e inizio giugno, scomparendo verso la metà del mese di giugno. Per riprendere nel periodo autunnale. Nel 2013 l’infestazione è ripresa nella seconda decade di luglio in concomitanza alla emissione di nuovi getti vegetativi conseguenti ad una irrigazione, con valori paragonabili a quelli primaverili. Le differenze delle percentuali di infestazione rilevate ai quattro punti cardinali non sono statisticamente significative. I campioni sottoposti ad analisi sono tutti risultati esenti da virus

Female-released sex pheromones mediating courtship behavior in Lysiphlebus testaceipes males.

Ethological aspects and chemical communication at close-range between the sexes of Lysiphlebus testaceipes Cresson (Hymenoptera: Braconidae) have been investigated through behavioral bioassays and chemical analysis. The attractiveness toward males of whole-body extracts of females and males in hexane and acetone was evaluated, adopting male fanning behavior as a key behavioral component. Also, the activity of polar and nonpolar fraction of female-body extract in hexane obtained using solid-phase extraction technique was investigated. In order to identify cuticular compounds, male and female whole-body extracts with hexane and acetone were analyzed by gas chromatography-mass spectrometry. The results showed that males exhibit a behavior including 4 phases when exposed to virgin females: premount, mount, copulation, and post-copulation. A preliminary courtship of the male included wing fanning, an extension and vibration of the wings for 1 to 2 seconds. Also, some original aspects not described for other species were carried out. The average duration of the entire sequence of events was 138.80 ± 19.51 sec. Also, males displayed significantly more wing fanning behavior in response to female whole-body hexane extracts (70.83%) than female whole-body acetone extracts (33.3%). Furthermore, males did not respond to male-body extracts or to the control (pure hexane and acetone), suggesting that the sex pheromone is composed of cuticular hydrocarbons that are also involved in the male courtship behavior. When hexane extracts of whole females were fractionated on silica gel and exposed to males, more activity was recorded for the nonpolar fraction (50.0%) than the polar fraction (27.7%), but no significant statistical difference was found. Significant differences were detected comparing the control (not fractionated extract) with the polar fraction, but not with the nonpolar fraction. A homologous series of n-alkanes with chain lengths from C19 to C30 carbon atoms was identified and quantified in the solvent extracts of wasp males and females. Between male and female extracts, there was a statistically significant difference in the average quantity of some of these hydrocarbons, such as C27, C28, and C29