117,587 research outputs found
. Un approccio sostenibile alla gestione di Musca domestica negli allevamenti: il controllo biologico
No full textBehavioural patterns in kalotermes flavicollis (Isoptera: Kalotermitidae): A preliminary investigation
No full textQuando la lotta biologica è un successo: Torymus sinensis, efficace antidoto contro le infestazioni da vespa cinese del castagno in Emilia Romagna
No full textLa “Vespa Cinese del Castagno” Dryocosmus .kuriphilus, è una tra le più recenti problematiche del castagno. I danni provocati da questo cinipide di origine cinese si manifestano con la formazione di galle a seguito dell’ovodeposizione e dello sviluppo larvale all’interno delle gemme con conseguente deperimento generale e riduzione della produzione. In Italia la vespa cinese è stata importata accidentalmente in Piemonte nel 2002, in Emilia Romagna questo parassita è presente dal 2008 e si è rapidamente diffuso in tutte le aree castanicole regionali.
Per l’importanza che il castagno riveste nella tradizione, per tutelare la sua funzione ecologica nell’ecosistema montano e per il valore economico che riveste, il Servizio Fitosanitario Regionale dell'Emilia Romagna ha scelto di impostare una strategia sostenibile per gestire D. kuriphilus, il controllo biologico tramite il parassitoide specifico Torymus sinensis, attuando e in parte modificando il protocollo realizzato dal DISAFA di Torino, centro che in Italia aveva curato l’importazione dell’antagonista naturale. Tale protocollo prevedeva la selezione e gestione di apposite aree di moltiplicazione, ossia di castagneti con caratteristiche idonee allo sviluppo del parassitoide e alla raccolta massiva delle galle del cinipide, e la gestione in laboratorio degli sfarfallamenti e delle unità di rilascio del parassitoide, poi distribuite tra i castagneti regionali.
Questo capitolo riguarda l’attività svolta negli anni 2012-2015, e dimostra come sia stato possibile ottenere un incremento delle unità di lancio, grazie alla sincronizzazione della gestione delle galle raccolte in funzione dei siti di rilascio. L’elevato numero di T. sinensis ottenuti indica un buon livello di adattamento e capacità riproduttiva del parassitoide, che ha consentito l’applicazione del controllo biologico del cinipide del castagno su buona parte del territorio regionale
Control of Hyalesthes obsoletus Signoret, vector of Bois Noir, using entomopathogenic agents: preliminary results.
No full textControl of Hyalesthes obsoletus, vector of Bois Noir, using entomopathogenic agents: preliminary resultsN. Reggiani1, N. Mori2 , L. Maistrello11 University of Modena and Reggio Emilia, Department of Agricultural& Food Sciences, via G.Amendola 2, Pad. Besta, 42100 Reggio Emilia, Italy2 University of Padova, DAAPV - Entomology, v.le dell’Università 16, 35020 Legnaro (PD), ItalyEmail: [email protected] planthopper Hyalesthes obsoletus Signoret (Homoptera, Cixidae) is vector of the grapevine yellow Bois Noir, one of the most important phytoplasmosis in Europe. Reduction of phytoplasma associated diseases incidence relies on the control of the insect vectors and on the eradication of affected host plants. Management of Bois Noir is especially difficult because 1) both the vector and the phytoplasma can develop also in plants other than grapevines and 2) the overwintering younger instars of the insect live underground feeding on the roots of wild plants normally nearby vineyards (like nettle and bindweed) and chemical treatments are ineffective and unsustainable (Mori et al., 2008). The aim of this work was to evaluate the possibility to control the young forms of the leafhopper by means of entomopathogenic agents applied to nettle roots (AAVV, 1997; Vanesa Toledo et al., 2007, Reggiani and Maistrello, 2010). A first semi-field test was performed on young leafhoppers obtained from hundreds of wild H. obsoletus adults that had been captured and allowed to breed in a greenhouse with nettle pots during the previous summer. In late spring, pots containing groups of these juveniles were treated by sprinkling the ground with selected strains of entomopathogenic fungi (Beauveria bassiana and Paecilomyces lilacinus) and nematodes (Heterorhabditis bacteriophora and Steinernema feltiae). The mortality of H. obsoletus was recorded on day 7, 14, and 21 after the treatment. A second trial was made in field conditions selecting plots (3 m2 surface) in proximity of vineyards with a high quantity of nettle. These plots were sprayed on the middle of July at the ground level with the same enthopathogenic agents strains used for the first test. The plots were isolated with proper cages and the number of emerged adults was monitored during the whole flight period using yellow sticky traps. The obtained results show a good activity of the tested biopesticides, in particular for B. bassiana in the semi-field trial, and for nematodes in the field trials. The experiments suggest that microbiological control of the planthopper vector could represent a promising option for the integrated management of Bois Noir. Key words: Bois noir, entomopathogenic agents, Hyalesthes obsoletus, microbiological control, biopesticidesReferencesAAVV -1997- Manual of Techniques in Insect Pathology. Academic Press Inc. San Diego, California - USA. Edited by Lawrence Lacey, 409 pp.Mori N., Pavan F., Bondavalli R., Reggiani N., Paltrinieri S., Bertaccini A., -2008-. “Factors affecting the spread of “Bois Noir” disease in north Italy vineyards”. Vitis: 47 (1), 2008: 65-72Reggiani N., Maistrello L. -2010- “An approach to the control of Hyalesthes obsoletus, vector of Bois Noir, using entomopathogenic agents ”. In: Proceedings of IX European congress of entomology, Budapest (HU) 22-27 August 2010, 143-144Vanesa Toledo A., Marino de Remes Lenicov A.M., Lòpez Lastra C.C. -2007- “Pathogenicity of fungal isolates (Ascomycota: Hypocreales) against Peregrinus maidis, Delphacodes kuscheli (Hemiptera: Delphacidae), and Dalbulus maidis (Hemiptera: Cicadellidae), vectors of corn diseases.” Mycopathologia 2007 163:225-23
Amino acid content and nectar choice by forager honeybees (Apis mellifera L.)
No full textDual choice feeding tests were performed to determine a preference of forager honeybees for specific amino acids. Artificial nectar containing proline was preferred over that containing only sugars. Nectar containing alanine was preferred on the first day, but preference was no longer significant thereafter. On the contrary, a negative response was found for serine. When the bees were given the choice between two nectars enriched with different compounds, proline was preferred above both alanine and serine, and alanine above serine
Population dynamics of Procambarus clarkii as a function of the body submersion/floating stage
No full textProcambarus clarkii (Girard, 1852) is a freshwater crayfish, native of Southern USA, which spread in Europe after its introduction for aquaculture. Little information is available on the decomposition of bodies in freshwater systems, yet the study of body transformations in this environment is important for the estimation of the minPMI and the alterations of the body that may affect the estimation of the cause of death. In previous experiments, the importance of P. clarkii in the consumption of dead bodies in freshwater systems was assessed.
A new series of experiments was set out in order to analyze the population dynamics of P. clarkii in relation to the position of the body in the water column, and, therefore, with the decomposition stage of the carcass. The experiments were performed in Nonantola (MO), Northern Italy (both during summer, one in July and the other in August). In each experiment, five pig carcasses (Sus scrofa, L) enclosed in lobster pots were placed inside an artificial freshwater dew pond (67m x 15m, with a maximum depth of 1,5m). The number of P. clarkii detected on each carcass was recorded following an established sampling protocol, together with water level and meteorological data.
Results of both experiments show two main crayfish population peaks on the carcasses: the first peak occurs immediately after the deposition of the body inside the pond and the second one occurs 7-10 days after the placement, at the end of the floating stage. This peculiarity is probably connected with a difficulty for the crayfish to reach the carcasses during the floating stage, because of their poor swimming ability. Both peaks occurred in the submersion stage, with the carcass lying on the pond bottom, where it was easily reachable by crayfish.
This study is important in the forensic field related to freshwater systems, because the feeding activity of P. clarkii is crucial in the dismemberment of the body in water. These experiments showed differences in the colonization of the body in relation to its position in the water column. This may be useful for the estimation of the minPMI interval on bodies found in freshwater ponds
Effect of chestnut tannins on the root-knot nematode Meloidogyne javanica
No full textAmong the natural products extracted from plants, tanninshave been reported to possess antihelmintic propertiesespecially for gastrointestinal nematodes in ruminants.Also, they are toxic to a wide range of fungi, bacteria andyeasts. Therefore, an in vitro and a glasshouse pot experimentswere undertaken to evaluate the effect of chestnuttannins on the control of the root-knot nematode Meloidogynejavanica. In the in vitro experiment, different tanninconcentrations in a geometric scale (from 0.32 to 20.48g/l), were tested for their effect on hatching of the nematode,whereas in the pot experiment, 100, 250 and 450g/m2 of tannins in aqueous solutions, were used in pots attransplant or at transplant and two weeks later for theireffect on nematode control. In both experiments treatmentswere compared to untreated and fenamiphos-treated controls.In vitro a nematostatic effect of tannins was observed,whereas in the pot experiment a significant reductionof eggs and juveniles/g root, total population densityand reproduction rates of the nematode were recorded. Theanatomical changes induced by M. javanica in tomatoroots treated with tannins did not differ from those producedby this and other Meloidogyne species on varioushosts reported earlier
Parasitisation activity of Spalangia cameroni and Muscidifurax zaraptor, pupal parasitoids of Musca domestica
No full textThe house fly, Musca domestica L. (Diptera: Muscidae), is a significant pest in livestock farms and a major concern for both humans and farmed animals due to its ability to transmit over 200 pathogens. The use of pupal parasitoids is a sustainable strategy for controlling this pest. Spalangia cameroni Perkins (Hymenoptera: Spalangiidae) and Muscidifurax zaraptor Girault & Sanders (Hymenoptera: Pteromalidae) are commonly used as biocontrol agents for M. domestica. The objective of this study was to determine the oviposition peak of female parasitoids in relation to their age and the sex ratio of the adult progeny. For both species, 20 fresh M. domestica pupae (24-48 h old) were provided daily to each fertilised female for 14 days, after which the pupae were checked for parasitoid emergence. A control group of 20 pupae without female parasitoids was maintained. The results showed that S. cameroni had a higher overall percentage of parasitisation (57.7%) compared with M. zaraptor (32.4%). The parasitisation ratio of S. cameroni remained almost constant throughout the 14-day period, whereas that of M. zaraptor decreased drastically after Day 11. Peak oviposition for S. cameroni was on Day 5 with 13 parasitised pupae per female, whereas M. zaraptor parasitised eight pupae per day on 4 days during its peak oviposition period (between Days 3 and 8). The newly emerged parasitoids had a skewed sex ratio towards females: 81% for S. cameroni and 66% for M. zaraptor. The presence of these parasitoid species resulted in fewer new house fly emergences than in the control group, where natural pupal mortality was lower in the absence of parasitoids. These findings may be useful for optimising the mass production and time-use of the two parasitoid species for the management of house flies in livestock farms
Il controllo dei nematodi nelle colture ortive: prove in vitro con i tannini di Castagno.
No full textThe effect of chestnut tannins was evaluated against some biological stages of Meloidogyne incognita. The nematicidal activity was tested at two concentrations (2-5 g/l) with and without bisulphite, for periods varying between 11 and 22 days. Treatment of 2 g/l of tannin stimulated significantly the embryogenesis and the juvenile hatching from unsegmented
eggs, whereas treatment at higher dose inibited and delayed the embryogenesis reducing the atching rate from eggs. This vegetable product revealed a very significant action on free juveniles motility showing nematostatic and mainly nematicidal properties at higher concentration. Finally tannin exhibited a significant inhibitory effect in hatching of juveniles included in eggmasses. All these properties make of this by-product
an interesting means for a new control strategy in nematode pest management
- …
