Search results for " Entomologia"

Effetto della localizzazione dello stress biotico sulle difese indotte in Vicia faba

2016

Le diverse fasi che caratterizzano l’attacco della pianta da parte del fitofago (contatto, alimentazione ed ovideposizione) inducono l’attivazione di meccanismi di difesa nell’ospite. E’ noto che le piante emettono composti volatili indotti in seguito all’attacco del fitofago e che questi volatili sono in grado di richiamare i parassitoidi. Nel caso specifico degli ooparassitoidi, tali difese indirette si esplicitano mediante rilascio di HIPV (herbivore-induced plant volatiles) ed in particolare di OIPV (oviposition-induced plant volatiles). Ad oggi non ci sono studi inerenti il ruolo giocato dalle tracce rilasciate dal fitofago sulla superficie vegetale nell’induzione di volatili utilizzat…

Impact of an invasive pest in local semiochemical networks

During the host location process, egg parasitoids rely on a series of chemical stimuli from the host/plant complex. In particular, in tritrophic systems consisting of plants, herbivorous stink bugs and their egg parasitoids, previous studies demonstrated that wasps are attracted by oviposition-induced plant volatiles (OIPVs). These compounds act as indirect plant defence mechanism allowing plants to recruit egg parasitoids, which are in general the most important natural enemies of stink bugs. Moreover, when wasps land on a plant, they can exploit chemical footprints left by male and female stink bugs walking on the leaves as indirect host-related cues, since chemicals lead them in an area …

Graphosoma (Graphosomella subgen. nov.) inexpectatum sp. nov. from Syria

2008

Foraging behaviour of a scelionid egg parasitoid exploiting chemical footprints from associated and non-associated host

2017

Chemical footprints deposited by herbivorous pentatomid host bugs hosts when walking on the plant are adsorbed by leaf surfaces and perceived as substrate borne semiochemicals by scelionid egg parasitoids during host selection process. They act as indirect host-related cues, as they are not able to “promise” to parasitoid females the presence of the suitable host stage, but they drive them in the areas where their hosts are potentially present. Once in contact with host chemical footprints, scelionid wasps evidence an innate arrestment response characterized by an intense searching behaviour on host-contaminated areas. Exploiting of these cues allows the parasitoids to optimize their search…

Western European Populations of the Ichneumonid Wasp Hyposoter didymator Belong to a Single Taxon

2019

Hyposoter didymator (Hymenoptera, Ichneumonidae) is a generalist solitary endoparasitoid of noctuid larvae. In the present work, we tested whether populations of H. didymator were divided in several genetically distinct taxa as described for many other generalist parasitoid species, and whether differences in H. didymator parasitism rates were explained by the insect host species and/or by the plant on which these hosts were feeding on. The genetic analysis of natural populations collected in different regions in France and Spain on seven different insect hosts and seven different host plants (775 individuals) showed that H. didymator populations belong to a unique single taxon. However, H.…

Scolitidi e loro parassitoidi sfarfallati da piante esca di pino laricio e pino d'Aleppo sull'Etna e sui monti Iblei.

2011

In due differenti pinete della Sicilia in cui si sono registrati recenti attacchi di scolitidi, in collaborazione con l’Azienda Foreste Demaniali, a fine autunno 2008 e 2009 alcune piante sono state abbattute e lasciate sul letto di caduta, intere e con chioma, fino alla primavera successiva in attesa della colonizzazione di coleotteri scolitidi. Nel demanio Sparano, (Noto, SR) a 620 m s.l.m., sui monti Iblei sono state abbattute piante esca di Pinus halepensis, mentre in due località del Parco dell’Etna, Passo Silletta (1200 m s.l.m.) e Secondo Monte (1600 m s.l.m.), sono state abbattute piante esca di Pinus laricio. A maggio dell’anno successivo, parti di fusto di diametro crescente lungh…

New Data on Ichneumonid Hibernation(Hymenoptera: Ichneumonidae)in the Barnova Forest Massif (Iasi County, Romania)

2014

In this paper the authors present the results of their researches made in the period of 2006–2010 on the hibernation of some ichneumonid species in the Bârnova forest massif (Iaşi county). 30 species of ichneumonids (only females) belonging to 20 genera of the the subfamily Ichneumoninae were recorded. Five of these species are new as hibernating. During the studied period there were established 6 hibernating stations, but with a low abundance.

The biological control applied in Citrus orchards against harmful exotic pests in Sicily (Italy)

2018

The citrus groves are injured by infestations caused by indigenous species or old and new phytophagous introduced. Several problems have found in the biological control a optimal solution that allowed a considerable reduction in the use of chemical products. In fact, applications of programs using biological methods has been more successful on citrus than in any other cropping system. Sicily (Italy), due to its location in the Mediterranean Sea, represents an island particularly rich flora and fauna with a characteristic biodiversity different from those of other countries and regions of Italy. It produces about 60% of the national citrus production with more areas of organic citrus groves.…

Integrating natural enemies and semiochemicals in cultural control for an effective IPM

2012

Since their discovery, many semiochemicals (behavior modifying chemicals) have been identified and synthetized, and a number of techniques have been developed to use them in integrated pest management (IPM) programs against insect pests. In particular, the uses of semiochemicals in IPM to monitor insect pest populations and to interfere with their behavior preventing agricultural damage are widely adopted by the growers. In the same time, evidences that semiochemicals can also modify the behavior of insect natural enemies inspired researchers to explore the possibility to use semiochemicals to conserve and/or enhance the efficacy of natural enemies in cropping systems. However the use of se…

Risultati preliminari del monitoraggio di lepidotteri diurni in un sito di interesse comunitario per differenti scopi applicativi

2010

Durante il XX secolo e specialmente negli ultimi 50 anni è stato riportato un declino nel numero specie di lepidotteri diurni presenti in Europa, ed ad una modificazione delle comunità delle farfalle. Tale decremento è stato attributo a diversi fattori: frammentazione e la scomparsa degli habitat e l'intensificazione dell'agricoltura e delle pratiche ad essa connesse. L'introduzione di nuovi prodotti in agricoltura, quali ad esempio le piante geneticamente modificate o i prodotti a base di virus entomopatogeni hanno posto ancor più l'accento sulla necessità di monitorare i lepidotteri non target (principalmente i diurni) sia come data set iniziale sia per i piani di post monitoring. A tal f…