57 research outputs found
The Past and Present of Pear Protection Against the Pear Psylla, Cacopsylla pyri L.
This chapter discusses the history of strategies and methods to control Cacopsylla pyri (Hemiptera Psyllidae) on pear trees, with special attention to new active ingredients and their effects on the pest and on the beneficial insects, and also to resistance development phenomena. In the past decade Italian and European populations of C. pyri have been less damaging, probably because of success of integrated pest management (IPM) programs. In Northern Italy orchards the most common defense strategy against C. pyri involves treatments on second-generation pests by abamectin, or less frequently by spirodiclofen. The autumn and winter treatments based on synthetic pyretroids are common in France and North America but rarely employed in Italy because of high toxicity against auxiliary insects. Concerning the development of resistance, as for other phytophagous species, also for C. pyri it has been found that some insecticides employed in the past induced resistance. Surveillance programs have therefore been established in Northern Italy and Spain for abamectin: no relevant resistance effects have been yet detected, but since LC50 and LC90 values are always higher in populations undergoing repeated abamectin treatments, the pear orchards where C. pyri outbreaks recently occurred are still under close investigation
Cloning, molecular characterization and tissue exPression of an octoPamine/tyramine recePtor from sPotted wing drosoPhila (DROSOPHILA SUZUKII)
Spotted wing Drosophila (Drosophila suzukii) is a polyphagous pest arrived in Europe in 2009 able to infest a growing number of fruit and vine
species, causing considerable economic damage. D. suzukii grows very rapidly (seven to fifteen generations per year) and shows a remarkable
ability to adapt to climatic conditions and to new host plants. These characteristics make its populations particularly difficult to control. Octopamine
(OA) and tyramine (TA) biogenic amines are present in traces in vertebrates, while in invertebrates they act as substitutes for adrenaline and
noradrenaline. Indeed, these amines regulate numerous physiological processes in insects. They exert their effects by binding to specific receptor
proteins that belong to the superfamily of G-protein coupled receptors (GPCRs). In this work, we have isolated complementary DNA (cDNA) coding
for an amine receptor from Drosophila suzukii (DsTyr). The cloned cDNA is about 1.8kb long and encodes for a 601 amino acids protein. This
polypeptide presents the classical seven transmembrane domains as revealed by hydropathic profile analysis. BLAST analysis of the sequence
shows a high identity (>98%) to the octopamine/tyramine receptor from Drosophila melanogaster. DsTyr1 deduced sequence will be compared to
the amino acid sequence of octopamine/tyramine receptors from other insects. Furthermore, the various receptor sequences will be characterized
by phylogenetic analysis. The expression level of the receptor will be studied by qRT-PCR analysis in different parts of D. suzukii male and female
body (head, thorax and abdomen). With this work, we present a first structural and functional description of an octopamine/tyramine receptor from
Drosophila suzukii
Mating behaviour and dual mode communication of Pear Psylla CACOPSYLLA PYRI
Cacopsylla pyri (L.) (Hemiptera, Psyllidae) is one of the most important pests of European pear, and its management generally depends on the use
of chemical insecticides, but C. pyri outbreaks are sometime observed. Ecological control strategies should be desirable and the knowledge of mating behavior is crucial to develop new ones. A multi-approaches research aimed to acquire knowledges about C. pyri mate finding. Electroantennographic (EAG) analyses and olfactometric bioassays were used to evaluate the activity of intraspecific semiochemicals on C. pyri. The EAG amplitudes revealed that volatile compounds, present in female cuticular extracts, elicited dose-dependent responses in males, indicating that these compounds were able to stimulate the male olfactory system. In behavioral bioassays, living females and female cuticular extracts, attracted summerform males in a highly significant manner. Gas chromatography-mass spectrometry revealed that 13-methylheptacosane, 11,13-dimethylheptacosane, 2-methylheptacosane and 3-methylheptacosane were found in larger amounts in female extracts than in male ones, which suggests their role in male attraction. In addition, a laser vibrometer device was used to detect a male-female substrate-born vibrations pattern during pre-copulatory period. The female vibrational signal was recorded as mp3 and conveyed, in loop using a minishaker, on pear shoots with C. pyri virgin pairs to interfere with the mating by masking the natural communications
Preliminary Investigation on the Toxicity of Different Formulations on Some Groups of Beneficial Arthropods in Emilia-Romagna Orchards
Control of the most relevant phytophagous of apple and pear trees in Emilia-Romagna (Northern Italy) is achieved by insecticides but it is improved also by defence techniques allowing protection of useful insects. It is therefore relevant to understand in detail the effects of the most common insecticides employed in integrated defence of the two above mentioned cultures on the main auxiliary insects, both predators and parasitoids. With this aim we performed open field tests to evaluate the acute toxicity (48 hours after the treatment), according to the method suggested by IOBC Working Group "Integrated Protection in Orchards" to test three recently developed active ingredient: Spinosad, Indoxacarb and Methoxyfenozide. These three principles were compared to Azinphos methyl, presently one of the most widely employed insecticides with a broad action spectrum. Spinosad is a natural insecticide compound, whose active principle is a toxin produced by Saccharopolispora spinosa, Indoxacarb and Methoxyfenozide are synthetic molecules, respectively belonging to the family of oxadiazines and moult accelerators, while Azinphos methyl is an organophosphate compound. The results show that Azinphos methyl is characterized by a lower selectivity towards generic Coccinellidae, while mortality towards Antochoris nemoralis is rather limited for all active principles tested, on the contrary to what observed for parasitoid Hymenoptera
Mining genes involved in indoxacarb resistance of Lobesia botrana (Denis and Schifferm\ufcller) by de novo transcriptome assembly and differential expression analysis.
Lobesia botrana (Denis and Schifferm\ufcller) (Lepidoptera: Tortricidae) is one of the most important grapevine pests in Europe but, being a non-model organism, only limited genomic and transcriptomic resources are available for functional studies at the molecular level, such as those relevant to insecticide resistance and pest control. Hence, to gain insight into the mechanism of indoxacarb resistance, a blocker of insect voltage-gated sodium channels (NaV), we analysed the transcriptome and expression profile in 2nd instars of L. botrana from susceptible and field selected populations (LC50 resistance ratio 72). De novo transcriptome assembly using Trinity resulted in 141,581 isoforms clustered in 94,290 putative genes. The transcriptome completeness was supported by BUSCO: 92% of conserved orthologs (n= 1,658) were retrieved as a complete sequence, 6.3% displayed fragmented ORFs, and only 1.7% were missing. 36,250 genes were preliminary annotated relaying on the longest isoform per gene, by running Annocript pipeline against non-redundant protein databases (Nr), gene ontology (GO), cluster of orthologous groups of proteins (COG), KEGG orthology (KO) and long non-coding RNAs (lncRNAs). Conditional Reciprocal Best BLAST analysis of protein isoforms performed on Lepidoptera proteomes identified putative orthologs of multigene family members potentially involved in metabolic resistance (61 cytochrome P450 monooxygenases, 25 glutathione S-transferases, 13 carboxylesterases, 25 UDP-glucuronosyltransferases) as well as alternatively spliced isoforms of the NaV gene. Among 263 upregulated and annotated genes in the resistant population, functional GO enrichment analysis revealed overrepresentation of terms for cytochrome P450, due to up-regulation of CYP6B and CYP9A subfamily members as well as increased transcript level for UGT genes. Hydrolases were, on the contrary, overrepresented in 293 annotated genes, downregulated in the resistant population. These data tentatively suggest the reduced susceptibility to indoxacarb might be related to an increase of Phase I and II detoxification along with reduced bioactivation of the insecticide
Implementation and Characterization of Vibrotactile Interfaces
While a standard approach is more or less established for rendering basic vibratory cues in consumer electronics, the implementation of advanced vibrotactile feedback still requires designers and engineers to solve a number of technical issues. Several off-the-shelf vibration actuators are currently available, having different characteristics and limitations that should be considered in the design process. We suggest an iterative approach to design in which vibrotactile interfaces are validated by testing their accuracy in rendering vibratory cues and in measuring input gestures. Several examples of prototype interfaces yielding audio-haptic feedback are described, ranging from open-ended devices to musical interfaces, addressing their design and the characterization of their vibratory output
The Italian National External Quality Assessment Program in Cytogenetics: 4 years of activity (2013-2016) following the introduction of poor performance criteria
Background. Italian External Quality Assessment (IEQA) Program in Cytogenetics, established in 2001 by the Istituto Superiore di Sanità (ISS), covers both Constitutional and Oncohaematological diagnosis. In 2013, performance criteria were defined and adopted. In this paper, we present the data from the first 4 years of activity (2013-2016) following the introduction of performance criteria. Methods. The enrollment is voluntary, fee-based and open to both public and private Italian laboratories. The scheme is annual and retrospective; a national panel of experts assess technical, analytical and interpretative performance. Results. Overall, 95 distinct Italian laboratories participated in different Cytogenetics IEQA schemes over the 2013-2016 years and most of the laboratories took part in Constitutional diagnosis. General hospitals and local health centers represented 40% of the total participants and the percentage of laboratories from Northern Regions was more than 45% of total participants throughout the 4-year period. As regards the performance evaluation, on average, 11, 9 and 23% of participants were marked as poor performers in Prenatal, Postnatal and Oncohaematological schemes, respectively. With regard to critical errors, ISCN nomenclature in Prenatal and Postnatal schemes, and interpretation in Oncohaematological diagnosis, were identified as main issues. On the other hand, karyotype errors and inadequate analysis decreased strongly, over the 4 years, in Constitutional and Oncohaematological diagnosis, respectively. Conclusions. Our data show that the introduction of poor performance encourages laboratories to address critical issues, and the IEQA participation helps to improve quality in cytogenetic testing.Â
Evaluation of insecticide efficacy and insecticide adaptive response in Italian populations of Drosophila suzukii
Monitoring sensitivity to insecticides is crucial to prevent outbreaks of invasive pests characterized by high reproductive and adaptive potential such as the Drosophila suzukii (Matsumura) (Diptera Drosophilidae). The aim of the present study was to investigate the possible appearance of resistance to cyantraniliprole, deltamethrin and spinosad. Field trials on commercial sweet cherry orchards in Northern Italy showed that two out of six strains were not fully controlled using cyantraniliprole and deltamethrin, while spinosad was thoroughly effective. At the bioassay, two populations showed a decrease in deltamethrin and cyantraniliprole susceptibility (LC50 values 12.7-21.0 and 3.4-5.8 times higher than those from the untreated populations, respectively). Biochemical analyses revealed that low resistance to the pesticides was associated with high monooxygenase and carboxylesterase activities
(range 2.68-4.37-and 1.97-2.73 times higher than in the wild population). A dose-dependent increase in cytochrome P450 monooxygenase Cyp12d1 and ryanodine receptor gene expression was found when a strain with low resistance to cyantraniliprole in field trials was treated with increasing dosages of the diamide in bioassays. No mutations were detected in voltage-gated sodium channel
and ryanodine receptor genes, which accounted for the reduction in pyrethroid and diamide susceptibility in other pests. After 8
generations of selection, starting from a susceptible population, the LC50 values of cyantraniliprole and deltamethrin were increased
2.2 and 25.0 fold, respectively, compared with the unselected colony. In contrast, no selection was possible for spinosad. Our study
would suggest that spotted wing drosophila, upon continued selective pressure, are more prone to develop low resistance to cyantraniliprole and deltamethrin than spinosad. The adaptive response relies on detoxifying activities of monooxygenases and increased
Cyp12d1 and ryanodine receptor gene expression
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