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Among Reticulitermes genus the most abundant species living in Italy is Reticulitermes lucifugus Rossi. This termite is very dangerous to wooden structures of artistic heritage and buildings. The traditional control of R. lucifugus is very difficult resulting in negatively impact on the environment, therefore the use of phytochemical, such as essential oils (EOs), could lead to an alternative to synthetic insecticides, with advantages in reducing environmental risks. In this work we investigated the insecticidal activity of EOs of Citrus bergamia Risso, Syzygium aromaticum L., Foeniculum vulgare Mill., Pelargonium odoratissimum L., and Origanum vulgare L. by inhalation against R. lucifugus workers. It is the first study to examine the efficacy of EOs on this termite species. Results showed that after 24 hours of treatment exposure, mortality occurred in all treatments and was dose-dependent, increasing when the treatment dose increased. At the lowest dose (2.5 μl/l), oregano, clove, and geranium EOs resulted in mortality of more than 80%. Oregano EO was the most active already at low doses, while fennel EO was the least effective. 24 hours after the treatment, the lowest DL50, obtained by the dose-response analysis, was detected for oregano EO (1.21 μl/l), followed by those of EOs of clove (1.28 μl/l), geranium (1.73 μl/l), fennel (2.20 μl/l), and bergamot (2.88 μl/l). This study highlighted the possibility of using these EOs in the termite control for the preservation of wooden structures.

The present study was conducted on protist species from R. lucifugus “Sicily” 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. “Sicily”. 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. “Sicily”. 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 ± 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.

È ormai opinione diffusa che la diversità vegetale all’interno degli agrosistemi favorisca il mantenimento dell’entomofauna utile ai fini di un contenimento naturale di fitofagi. In quest’ambito, il presente lavoro ha riguardato uno studio, sulle popolazioni di Empoasca vitis e del suo parassitoide Anagrus atomus in un’azienda viticola sita nel comprensorio di Salemi (TP) (446 m s.l.m.) a conduzione biologica prendendo in considerazione due appezzamenti, uno con ai margini siepi di rovo, rosa canina e rosmarino e l’altro in assenza di siepi. Nel periodo vegeto-produttivo della vite (marzo-ottobre 2012), si è valutata l’influenza della specie vegetale e della variazione della distanza delle siepi dal vigneto (10, 50 e 100 m) sulle catture degli adulti di E. vitis e del suo antagonista A. atomus usando trappole cromotropiche gialle e sulla distribuzione degli stadi giovanili del fitofago mediante campionamenti di foglie. I risultati hanno messo in luce un’influenza positiva delle siepi sul contenimento di E. vitis e che questa dipende dalla distanza delle siepi dal vigneto. Inoltre differenze nei livelli di popolazione sono state rilevate tra le specie vegetali, con maggiore presenza su rovo. Bisogna comunque evidenziare che, in tutto il periodo di osservazione, la popolazione del fitofago è sempre stata al di sotto della soglia di intervento, probabilmente sia per l’andamento climatico del periodo, sfavorevole alla cicalina, sia per la presenza delle siepi, impiantate già da diversi anni, che ha portato ad un equilibrio biologico nel vigneto. Influence of ecological infrastructures at the edge of the vineyard on Empoasca vitis (Goethe) (Homoptera: Cicadellidae) and its parasitoid Anagrus atomus L. (Hymenoptera: Mymaridae) It is widely accepted that plant diversity in agrosystems helps to maintaining entomophagous insects useful for a natural control of pests. In this context, the present paper concerns a study on populations of the green grape leafhopper Empoasca vitis Goethe (Homoptera: Cicadellidae) and its parasitoid Anagrus atomus (L.) (Hymenoptera, Mymaridae)in an organic vineyard located in Salemi (446 m a.s.l.), (TP) Sicily, in biological management from March to October 2012, considering two plots, one with hedges of Rubus ulmifolius Schott, R. canescens D.C., Rosa canina L. and Rosmarinus officinalis L. and the other in the absence of hedges. We evaluated the influence of plant species and the variation of the distance of the hedges from the vineyard (10, 50 and 100 m) on flights of E. vitis and its antagonist both inside vineyards and in surrounding hedges, using yellow sticky traps, and on the distribution of young stages of the pest by samples of leaves. The results showed a positive influence of hedgerows on the control of E. vitis and this depends on the distance of the hedges from the vineyard. In addition, differences in population levels were detected between plant species, with major presence of bramble. Also, we noted the population of the pest has always been below the economic threshold, probably both the climate of the period unfavorable to leafhopper both for the presence of hedges, implanted for several years, which has conducted an ecological equilibrium in the vineyard

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.

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.

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.

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.

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.

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.

This work reports studies on the population dynamics and safe control strategies of Bactrocera oleae in four unsprayed olive groves of western Sicily from 2007 to 2010. The main management tools for B. oleae evaluated were the“Attract and Kill” lures (Ecotrap Vioryl), the use of sardines (traditional practice) and Nu-lure (innovative) and the spinosad (innovative) which is a selective insect control product produced by the fermentation of a naturally occurring soil bacterium, Saccharopolyspora spinosa. Flies trend were carried out by pheromone traps and the level of infestation counting the number of fruits with pest eggs, larvae and pupae and hole hatching. Results showed that in all olive groves and during three years of observation, the number of males caught by pheromone traps and infestation levels in the control areas were often higher than in the treated areas with baits. The lowest values were always detected in areas with sardine and Nu-lur baits. The infestation was always lower in the area treated with spinosad than in untreated area (control). The number of healthy olives from the areas treated with spinosad was on average 70%. The assessment of these ecological methods induces their application as control strategies with the aim of reduce the olive fruit fly population below economic threshold considering the low environmental impact.

Phyllonorycter delitella (Duponchel) (Lepidoptera: Gracillariidae) è un fillominatore che è stato rinvenuto nel 2004 nelle aree boschive siciliane su Roverella (Quercus pubescens Willd.). Nel presente lavoro si riportano i risultati delle indagini condotte sul feromone sessuale di questo fitofago, sotto il profilo comportamentale, chimico e morfologico. Per analizzare le risposte comportamentali di maschi vergini di P. delitella verso gruppi di femmine conspecifiche in fase di richiamo sono stati condotti biosaggi in olfattometro a due vie. Le prove hanno evidenziato un’attrazione significativa degli individui osservati verso le femmine vergini. Partendo da questi risultati è stata effettuata la raccolta in flusso d’aria dei volatili emessi rispettivamente da gruppi di femmine vergini, maschi vergini e femmine accoppiate. Le sostanze raccolte sono state eluite con solvente organico ed analizzate in un Gascromatografo interfacciato ad uno Spettrometro di Massa (GS-MS). Le analisi chimiche hanno evidenziato una diversa composizione quali-quantitativa tra i cromatogrammi ottenuti per le tre tipologie di individui studiati. Indagini ultrastrutturali condotte sia con il Microscopio Elettronico a Scansione (SEM) che con il Microscopio Elettronico a Trasmissione (TEM) hanno evidenziato la presenza di una ghiandola a feromone sessuale in corrispondenza del tratto dorsale della membrana intersegmentale tra l’VIII ed il IX segmento addominale. Le cellule secretrici dell’epitelio ghiandolare riversano il loro secreto attraverso micropori che perforano la cuticola soprastante. In posizione di riposo la membrana intersegmentale forma una cavità dove il secreto accumulato è successivamente rilasciato nella fase di richiamo sessuale. Alla luce di questi risultati l’impiego dei composti feromonali di P. delitella potrebbe rappresentare una valida alternativa per il monitoraggio delle popolazioni negli ecosistemi forestali

Role of oophagous parasitoids in the natural control of hazelnut bugs inducing the “cimiciato seeds” in Nebrodi Park (ME) Oophagous parasitoids of bugs collected on hazelnut cultivations and seasonal parasitism on eggs of Gonocerus acutengulatus (Goeze) were studied from 2004 to 2006 in the Nebrodi Park (ME). Samples of bug eggs were collected in three altitude areas, 300-590, 600-890 and 900-1100 m above sea level, and examined in laboratory. Parasitoid adults obtained from all eggs were identified. Parasitization levels, detected on G. acuteangulatus in all areas showed a similar trend with the most value on August. Significant regression between the total number of eggs and the number of parasitized eggs was found (R2=0.75). Parasitoid species detected were Anastatus bifasciatus (Geoffroy), Gryon muscaeformis (Nees), Telenomus viggiani Mineo and other three species not yet identified.

Study on the parasitoid complex of Prays oleae (Bernard) and parasitism levels in an organic olive orchard in western Sicily (Italy). Prays oleae is a serious pest of the olive tree in the Mediterranean basin. This phytophagous infests fruits (carpophagous generation) and leaves (phyllophagous generation). In cases of high population densities crop losses, caused mainly by fruit drop, may be heavy. The aim of this work was to investigate on 1) parasitoid species living on P. oleae, 2) their incidence parasitoid complex, 3) parasitism levels and 4)the influence on the fruit fall. Observations were conducted in an organic olive grove near Contessa Entellina (PA) (Sicily, Italy) (37.43.44 N; 13.10.14 E, 640 m s. l. m.). Samples of leaves, weekly, were collected, during the overwintered (phyllophagous) and March 2004 to July 2007. In laboratory, singly into vials and observed daily until the adult emergence.

Il lavoro è stato svolto in quattro aziende a conduzione biologica della Sicilia occidentale avvalendosi delle risorse finanziarie istituite dal MiPAF, con il “Fondo per lo sviluppo dell’agricoltura biologica e di qualità” ed in ambito regionale dall’attuazione da parte del Servizio IV dell’Assessorato Regionale Agricoltura e Foreste del “Progetto di Sviluppo dell’Agricoltura biologica in Sicilia” sottoprogetto “Gestione fitosanitaria dell’agrosistema olivo”. Vengono riportati i dati inerenti l’efficacia del metodo “attract and kill” nei confronti delle infestazioni della mosca delle olive. In ciascuna delle quattro aziende, tre situate in zone collinari (indicate con A, B e C) e una a livello del mare (indicata con D), sono state individuate delle parcelle di 2ha in A e B, seguite nel 2006 e nel 2007, e di 100 piante in B e C, seguite nel 2008, dove sono state poste delle eco-trap (Vioryl) così distribuite: azienda A tesi con 100 trappole/ha, azienda B tesi 1 con 100 trappole/ha e tesi 2 con 150 trappole /ha, aziende C e D tesi con 1 trappola/pianta. Per tutte le tesi sono state predisposte parcelle testimone e in tutte le parcelle sono state poste trappole a feromone in numero di 3/ha. Inoltre, sono stati rilevati i livelli di infestazione attraverso campionamenti settimanali di 100 drupe/ha per ciascuna parcella. I risultati ottenuti mostrano che nelle aziende A e B il numero di catture è sempre stato maggiore sul testimone rispetto alle tesi. Nell’azienda C, il numero di catture iniziate nella I decade di agosto,è stato superiore sulla tesi sino alla fine di settembre e da questa data in poi, sul testimone. Nell’azienda D, le catture sono state rilevate solo sulla tesi dalla fine di agosto sino a fine settembre e quasi esclusivamente sul testimone da inizio ottobre sino alla raccolta. L’infestazione attiva nel 2006 nelle aziende A e B ha mostrato valori sul testimone quasi sempre superiori a quelli della tesi, con andamento decrescente nell’azienda B. Nel 2007 nell’azienda A l’infestazione è stata quasi assente, mentre nell’azienda B è stata simile sulle due tesi ma sempre inferiore a quella sul testimone. Nel 2008, l’infestazione attiva rilevata nell’azienda C e nell’azienda D è stata sempre inferiore sulla tesi rispetto al testimone con valori, però, nettamente più bassi nell’azienda D. E’ da rilevare che i livelli di infestazione registrati sulle tesi con eco-trap non si sono discostati in modo apprezzabile da quelli rilevati sui testimoni.

Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae), is native to India, China, and other Southeast Asian countries that has spread rapidly since 1993 to all citrus-growing areas of the world. In Italy, the pest was first discovered during the autumn of 1994, in some citrus groves of Sardinia and, subsequently, in Sicily in the summer of 1995 showing a very rapid range expansion in other citrus-growing regions of Italy. Currently, damage to mature trees under typical Mediterranean conditions is considered only aesthetical, but P. citrella causes economic problems on young trees, nurseries, and overgraftings. Since the first occurrence of the citrus leafminer in Sicily, several indigenous natural enemies have been found attacking the pest, although only few parasitoid species were observed living on this phytophagous in the last years. The aims of this study were to monitor the population dynamics and mortality of P. citrella, and its natural enemies with parasitism levels, from 2002 to 2006, in some unsprayed citrus orchards in western Sicily, Italy. Results showed differences on dynamics of stages of P. citrella and of its parasitoid complex related to climate effects. Also, the monthly percentage mortality and parasitism are reported. The major percentage of parasitism was imputable to Citrostichus phyllocnistoides Narayanan and Semielacher petiolatus (Girault)..

Population dynamics and mortality of P. citrella, and its natural enemies with parasitism levels in two different citrus orchards, sprayed and unsprayed, were investigated. The effect of host density on percentage parasitism and mortality was calculated by regression analyses. In both sites, over the 3-years period from 2002 to 2004, P. citrella was detected during the summer months and it was not found during the first flush. Population levels were low, never exceeding 3.0/leaf. P. citrella began to increase from June in 2002-2003 and from July in 2004. The monthly percentage parasitism of P. citrella in sprayed orchard fluctuated from 0 to 19%, while in unsprayed from 0 to 30%. High mortality was found in both locations with maximum levels of 100%. No significant regression was found between CLM population and parasitism and mortality percentage. Small differences between results in two orchards were found

Il presente lavoro riporta uno studio pluriennale, dal 2000 al 2003, sulla evoluzione dell’infestazione e la dinamica della popolazione della mosca delle olive, Bactrocera (=Dacus) oleae (Diptera: Tephritidae), in agrosistema oliveto non soggetto a trattamenti chimici, allo scopo di individuare il momento di intervento e il metodo più idoneo da utilizzare per la lotta contro il fitofago. In particolare la ricerca è stata condotta in due oliveti a conduzione biologica siti in diverse località della Sicilia occidentale e ha riguardato l’andamento dell’infestazione totale (percentuale di olive con segni di attacco) e attiva (percentuali di olive contenenti uova, larve o pupe vive), le curve di volo dei maschi attraverso la cattura con trappole a feromone, la relazione tra il numero totale di catture dei maschi e l’infestazione attiva, la dinamica della popolazione di larve e pupe e l’andamento della loro mortalità. I risultati ottenuti mostrano che, in entrambi gli oliveti, i livelli di infestazione, totale e attiva, come anche le catture dei maschi spesso, superano le soglie di intervento. L’analisi della regressione lineare tra il totale delle catture dei maschi e il livello di infestazione attiva per ogni osservazione del periodo considerato ha mostrato una relazione significativa in uno dei due oliveti studiati. Inoltre, per tutto il periodo di osservazione, è stata riscontrata una presenza maggiore di larve, ad eccezione di alcuni periodi, quali fine luglio-inizio agosto del 2001 e del 2002 e novembre del 2002, in cui sono stati registrati picchi relativi alle pupe. La mortalità della mosca è stata riscontrata solo a carico delle larve con valori molto elevati in alcuni periodi, quali settembre del 2000 e del 2001 e fine agosto degli anni 2001, 2002 e 2003, probabilmente dovuti alle alte temperature. Questi risultati fanno ipotizzare una strategia di lotta che tenda ad abbassare la popolazione della mosca a livelli tollerabili, utilizzando mezzi a basso impatto ambientale come trappole cromotropiche, alimentari, “attract and kill” che, come riportato da altri autori, sembrano dare buoni risultati.

Tuta absoluta, an invasive pinworm characterized by high reproductive potential and adaptation to different agroecological conditions, cause serious damage to tomato crops. Chemical control with synthetic insecticides is widely used to control this pest, although pesticides exhibit side effects on non-target organisms and negatively impact the environment, with the occurrence of resistance to some active substances in the target pest. The use of essential oils (EOs) from aromatic or officinal plants could represent an environmentally safe control method, alternative to synthetic insecticide application. In this work we investigated the effect of EOs from Spanish oregano, laurel, basil, garlic, peppermint, cypress, and eucalyptus EOs on T. absoluta oviposition deterrence and larval repellency. Results showed a remarkable oviposition deterrence using laurel, Spanish oregano, basil, and garlic EOs in both laboratory and greenhouse experiments. In no-choice repellence tests carried 1, 2, 6, and 22 h after treatment application, peppermint and Spanish oregano EOs showed the most lasting effects while cypress and eucalyptus EOs were not effective after 6 and 22 h, respectively. In choice tests, at either 5 or 22 h after treatment application, low preference for the test over control by larvae was observed in all treatments, except for basil EO. The most promising effects were observed in Spanish oregano and laurel treatments where no larvae were detected. Repellent effectiveness of EOs does not seem to be influenced when larvae did not get a chance to do a choice between treated and untreated leaves. This study highlights the effectiveness of EOs of aromatic or officinal plants as an alternative to synthetic insecticides for the control of T. absoluta.

As part of the studies on the morphological color variation of insects, a case study on the seasonal body color variation of Cirrospilus pictus (Nees) (Hymenoptera: Eulophidae: Eulophinae) parasitoid of leafminers is reported. Observations were made from January 2000 to December 2003 in north-western Sicily (Italy), in relation to sex, body regions of adults and seasonal periods. Wasps parasitizing Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae) were collected from organic citrus orchards (Citrus limon L., var. “Femminello zagara bianca” and “Femminello comune”). Adults were grouped in classes: yellow males, black males, yellow females, yellow–black females and black females. The results highlighted a phenotypic pigmentation variation in the head, thorax, gaster and legs of individuals influenced by the season of sampling. Adults were yellow–green in summer months, whereas individuals with dark pigmentation were found in autumn and winter months. A correlation between color patterns and seasonal temperatures was found for both females and males. This work provides a contribution to the description of the intraspecific variability of this species, improving its identification.