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Il progetto IDRA è la base di una attività che sensibilizzerà e veicolerà agli agricoltori le conoscenze per una efficace e sostenibile difesa fitosanitaria contro il ragnetto rosso, ormai prima avversità animale per il pomodoro da industria in Pianura Padana

Testato l’effetto sinergico di acaricidi e sali di acidi grassi

Linee guida e formazione sono importanti tanto quanto gli agrofarmaci per contenere i danni causati dal ragnetto rosso su pomodoro

L’Oltrepò Pavese è un’area vocata tradizionalmente alla viticoltura soprattutto nella sua estensione collinare e rappresenta una delle più importanti aree per la produzione di vini di qualità nel Nord Italia. Nell’ambito del progetto “Oltrepò BioDiverso”, finanziato dalla Fondazione Cariplo, la diversa gestione dell’interfila dei vigneti (cv Croatina, Pinot noir, Barbera, Riesling italico, Merlot) è stata valutata con approccio multidisciplinare per determinare:a) biodiversità dei microartropodi valutando le loro abbondanze, indici ecologici come Shannon, Simpson, Margalef, QBSar, acari oribatidi/altri acari; b) composizione delle comunità di funghi e batteri del suolo a due diverse profondità (0-30 e 30-60 cm); c) caratteristiche fisiche (tessitura, porosità), chimiche (come TOC, TN, S) e idrologiche del suolo (CSC, contenuto idrico, ecc.). La ricerca è stata condotta ponendo a confronto 3 vigneti con interfilare lavorato solo superficialmente fino a 20 cm (Conservative Tillage - CT) e 3 vigneti con copertura vegetale naturale senza lavorazione (No Tillage - NT). Nel 2017 sono stati prelevati 3 campioni di terreno nell’interfila di ognuno dei 6 siti. Le comunità dei microartropodi raccolte sono state caratterizzate sulla base del loro adattamento morfologico alla vita nel suolo (forme biologiche). Il DNA totale dei batteri e dei funghi è stato estratto da campioni provenienti dalle due diverse profondità (0-30, 30-60 cm). L'assenza di lavorazione del terreno si ripercuote in una migliore conducibilità idraulica superficiale, con maggiori macroporosità e quantità di materia organica. In tale microhabitat edafico (NT), gli indici di biodiversità degli artropodi presentano valori più alti rispetto ai suoli lavorati (CT), mentre i valori medi di QBSar sono elevati (>140) in entrambi i casi. Le abbondanze totali presentano una distribuzione variabile in base alla località (F5,17= 9,25 p<0,001) probabilmente risentendo anche di altri fattori com

The evolution of resistance to insecticides threatens the sustainable control of many of the world’s most damaging insect crop pests and disease vectors. To effectively combat resistance, it is important to understand its underlying genetic architecture, including the type and number of genetic variants affecting resistance and their interactions with each other and the environment. While significant progress has been made in characterizing the individual genes or mutations leading to resistance, our understanding of how genetic variants interact to influence its phenotypic expression remains poor. Here, we uncover a mechanism of insecticide resistance resulting from transposon-mediated insertional mutagenesis of a genetically dominant but insecticide-susceptible allele that enables the adaptive potential of a previously unavailable recessive resistance allele to be unlocked. Specifically, we identify clones of the aphid pest Myzus persicae that carry a resistant allele of the essential voltage-gated sodium channel (VGSC) gene with the recessive M918T and L1014F resistance mutations, in combination with an allele lacking these mutations but carrying a Mutator-like element transposon insertion that disrupts the coding sequence of the VGSC. This results in the down-regulation of the dominant susceptible allele and monoallelic expression of the recessive resistant allele, rendering the clones resistant to the insecticide bifenthrin. These findings are a powerful example of how transposable elements can provide a source of evolutionary potential that can be revealed by environmental and genetic perturbation, with applied implications for the control of highly damaging insect pests.

Uno degli insetti infestanti gli ambienti antropici più diffusi a livello globale è Blattella germanica (L.). In questa specie la resistenza agli insetticidi è andata crescendo negli anni e si è tramutata in uno dei maggiori ostacoli all’attuazione di efficienti strategie di controllo. Attualmente le esche insetticide con formulazione gel mantengono una buona efficacia mentre i trattamenti convenzionali che prevedono l’uso di formulazioni spray, soprattutto di piretroidi, hanno dimostrato molti limiti. In letteratura risultano numerosi casi di inefficacia per diversi principi attivi nei confronti di B. germanica, rendendolo il secondo insetto urbano più resistente nella classifica mondiale. Una possibile soluzione a questo problema può venire dall’uso di sinergizzanti come il piperonil butossido (PBO), molecole senza o con trascurabile attività insetticida che, quando sono applicate in abbinamento a vari prodotti insetticidi, ne potenziano l’efficacia inibendo i sistemi metabolici di detossificazione presenti nell’insetto bersaglio. In questo studio, eseguito nell’ambito del progetto europeo “Ecosyn” (EcoSyn - Ecofriendly synergists for insecticide formulations, finanziato dal Settimo Programma Quadro dell’Unione Europea – Contratto no 605740), il PBO e alcuni suoi nuovi derivati sono stati combinati con insetticidi di già nota efficacia, quali cipermetrina e S-metoprene, per valutarne il possibile effetto sinergico. Per le prove con il piretroide è stato sviluppato un test per contatto lasciando gli insetti a contatto della superficie trattata per 30 minuti e valutando l’effetto knock-down ogni 5 minuti. La mortalità è stata valutata dopo 24 ore. In generale i vari sinergici non hanno aumentato l’effetto knock-down ma hanno causato un significativo aumento di mortalità rispetto all’insetticida usato da solo. Uno solo dei nuovi derivati ha dimostrato, quando usato da solo, una limitata tossicità nei confronti di B. germanica. L’esperimento con S-metopre

La sicurezza alimentare assume sempre più importanza sia per l’industria agro-alimentare sia per il consumatore. Igiene e qualità devono essere garantiti lungo tutta la filiera, dalla produzione al consumo. Nonostante le tecnologie di controllo attualmente disponibili, l’inquinamento da parte di infestanti, vertebrati o invertebrati, è tutt’altro che risolto. Oltre a violare i sopracitati requisiti igienici, rappresenta un limite merceologico, un danno commerciale per il produttore e un fastidio, a volte non limitato alla semplice vista ma legato alla salute, per il consumatore. L’esame degli alimenti può essere condotto con svariate tecniche, dalle più classiche diagnosi macroscopiche, ai metodi di microanalisi quali il filth-test, fino ad arrivare alle più moderne analisi del materiale genetico. Il filth-test è a tutt’oggi un prezioso strumento per la determinazione delle impurità solide di una matrice alimentare, indicatore diretto della sanità di un prodotto e indiretto dello standard igienico adottato nelle fasi di lavorazione e conservazione. Grazie a questa tecnica analitica è possibile osservare al microscopio frammenti di varia natura derivanti dall’agente contaminante. Sono di estrema importanza l’abilità dell’analista e, nel caso specifico degli artropodi infestanti, le sue conoscenze entomologiche. Una errata identificazione del contaminante può condurre ad una errata valutazione del problema e di conseguenza alla sua mancata risoluzione. Quando si incorre in simili difficoltà identificative può essere di grande aiuto un approccio molecolare. Il “DNA barcoding” è una metodica molecolare che consente l’identificazione di specie biologiche attraverso l’analisi di specifiche sequenze di DNA. La tecnica si è finora rivelata un valido supporto per il riconoscimento di macro-contaminanti animali rinvenuti nelle derrate alimentari, non identificabili con le classiche analisi morfologiche in quanto deteriorati dalla lavorazione e dallo stato di c, The quality assessment of foodstuffs is an important tool for agri-food industries: contaminated products can not be sold in the market because of sanitary problems and potential health risks for the consumers. Today, different techniques are available for the detection and identification of food contaminants. Macro-contaminations can be directly detected, whilst micro-contaminations can be discovered with filth test analyses; also, a molecular approach is possible and it is called ‘DNA barcoding’. Filth-test is a well-known method which allows the detection of arthropod fragments, hairs or other kind of solid impurities. After their finding, the final evaluation represents the most critical part, because great expertise is required to reveal their nature. This is important not only to assess the foodstuff quality, but also to infer information about the source or place of contamination in the production chain. DNA barcoding represents an alternative and useful approach for the identification of biological samples showing particular features (size, conservation or lack of diagnostic parts missed during foodstuff processing) that do not allow the use of traditional identification methods. It is based on the analysis of short and standardized fragments of genomic DNA, thanks to the development of the sequencing technologies and the availability of free on-line databases of previously characterized DNA sequences. In the last years, further advances have been made with the “metabarcoding”, a novel approach which combines the DNA barcode-base identification system together with the high-throughput ability of the next-generation sequencing (NGS) techniques. This method can be used to reveal the whole content of complex substrates like water, soil or foodstuff like flour and its derivatives, and it will be further investigated in the future for foodstuff analysis.

To assess the susceptibility of pseudocereals (amaranth and quinoa), minor cereals (teff and millet), and oilseeds (chia and hemp), now commercially available on the European market, to attacks by polyphagous and cosmopolitan insect pests, laboratory tests were set up. Tests involving controlled infestation of seeds, using laboratory-bred insects (Tenebrio molitor, Tribolium confusum, Oryzaephilus surinamensis, Cryptolestes pusillus and Plodia interpunctella), were carried out in a climatic chamber at 23±2 °C and 65±5% R.H.. Development time, the number of adults and the weight of these adults were evaluated. The results show that each considered foodstuff has a different susceptibility to infestation and differences both in the number of adults emerged and in their weight compared to control. Millet was the only product that allowed larval development up to the adult stage for all the species examined. No species developed on amaranth. T. confusum and O. surinamensis reached the adult stage on the greatest number of products, 5 and 4 respectively; C. pusillus and T. molitor completed their life cycles on only two commodities: millet and teff, while P. interpunctella only on millet and hemp seeds. Considering the impact of the different pests on the studied grains, T. confusum was the only species able to develop on all the grains, but the number of emerged adults was lower than on the standard diet. These results show that, even if these commodities are new in the European market, they are susceptible to the infestation of common stored product pests that could led to a removal from the market of a contaminated stock, so a continuous monitoring is needed.

Il volume comprende i testi estesi dei contributi presentati nel X Simposio "La difesa antiparassitaria nelle industrie alimentari e la protezione degli alimenti", svoltosi a Piacenza il 20-22 settembre 2017, a cura dei Prof.ri Emanuele Mazzoni e Rinaldo Nicoli Aldini. Il presente volume è il decimo di una serie relativa ai quinquennali simposi svoltisi presso la sede piacentina dell'Università Cattolica, avviati dal Prof. Giorgio Domenichini nel 1972 e proseguiti (dopo le prime cinque edizioni da lui curate) a cura del suo successore Prof. Piero Cravedi, fino alla nona edizione compresa. Ogni simposio ha visto la partecipazione attiva di docenti e ricercatori universitari del settore, esponenti di industrie alimentari, responsabili di enti pubblici preposti al controllo, addetti al comparto della disinfestazione, ecc.

The growing demand for healthy foods has recently brought new kinds of products to the Italian market to meet consumers’ needs. Currently, quinoa, teff and hemp seeds can be found quite commonly in most stores, as whole or broken grains or flour. These products can be susceptible to pest attacks in different stages of the production process: from storage as whole seeds through the transformation phases to the final products ready for consumption. The aim of this work is to verify susceptibility to infestations, even if only temporary, for these recently introduced products, by two of northern Italy’s most common stored product pests, known for their high polyphagy: Tenebrio molitor L. (Coleoptera: Tenebrionidae) and Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae). Artificial infestation assays were carried out to evaluate the mating and development possibilities for such pests on these grains. The growth rate of larvae, life cycle length and number of individuals which reached the adult stage were also assessed. Insects were obtained from colonies maintained under constant conditions in a climatic chamber (23 ± 1 °C and 65 ± 5% R.H.) at the Di.Pro.Ve.S. laboratory. These environmental conditions were maintained throughout all the assays. Insect colonies were fed on commercially available grains. Significant differences as regards the bionomical traits investigated under the above climatic conditions were observed for each species and the different grains

The soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae) is a serious pest of the soybean plant, Glycine max, a major world-wide agricultural crop. We assembled a de novo genome sequence of Ap. glycines Biotype 1, from a culture established shortly after this species invaded North America. 20.4% of the Ap. glycines proteome is duplicated. These in-paralogs are enriched with Gene Ontology (GO) categories mostly related to apoptosis, a possible adaptation to plant chemistry and other environmental stressors. Approximately one-third of these genes show parallel duplication in other aphids. But Ap. gossypii, its closest related species, has the lowest number of these duplicated genes. An Illumina GoldenGate assay of 2380 SNPs was used to determine the world-wide population structure of Ap. Glycines. China and South Korean aphids are the closest to those in North America. China is the likely origin of other Asian aphid populations. The most distantly related aphids to those in North America are from Australia. The diversity of Ap. glycines in North America has decreased over time since its arrival. The genetic diversity of Ap. glycines North American population sampled shortly after its first detection in 2001 up to 2012 does not appear to correlate with geography. However, aphids collected on soybean Rag experimental varieties in Minnesota (MN), Iowa (IA), and Wisconsin (WI), closer to high density Rhamnus cathartica stands, appear to have higher capacity to colonize resistant soybean plants than aphids sampled in Ohio (OH), North Dakota (ND), and South Dakota (SD). Samples from the former states have SNP alleles with high FST values and frequencies, that overlap with genes involved in iron metabolism, a crucial metabolic pathway that may be affected by the Rag-associated soybean plant response. The Ap. glycines Biotype 1 genome will provide needed information for future analyses of mechanisms of aphid virulence and pesticide resistance as well as facilitate c

A general overview of insecticide resistance mechanisms in stored product and urban pests is given. The most important cases of metabolic and target site resistance are discussed and recent discoveries about the resistance mechanisms to phosphine in Coleoptera are presented.

Varroa destructor is one of the major pests against honey bees. Beekeepers can rely on different approaches to try and prevent colony collapses, and the most relevant are acaricide treatments. Pyrethroid resistance was first reported in Lombardia in 1991 and is now spread worldwide. Recently, three different mutations (L925V/I/M) occurring in the voltage-gated sodium channel have been associated with tau-fluvalinate resistance. Furthermore, indirect evidence from laboratory bioassays indicated that high levels of esterases may be involved in mites resistant to tau-fluvalinate. This study provides an update of the actual spread of target-site resistance to tau-fluvalinate in varroa samples collected in the Lombardia region. TaqMan assays showed that mutation L925V is present in this area, however only low frequencies of this resistant allele were detected. The majority of resistant mites were found in the homozygous form (11%), and only a small fraction possessed the heterozygous genotype (2%). Additionally, a protocol was set up to detect esterase activity directly in single mites to determine if metabolic resistance can occur. We observed slight variability among different populations, and piperonyl butoxide showed only very low inhibition of this activity in vitro. Additional evaluation of monooxygenases activity must also be explored in the future.

In the most ancient wine area of the Controlled Denomination of Origin (DOC) “Oltrepò Pavese” in North-West Italy, foothills of the Apennine mountains, the soils of 14 representative vineyards managed for about 10 years with tillage (T) or natural grass-cover (G) or the alternation of the two methods between the rows (GT), were compared for their contents of organic matter, main soil parameters and extent of root development, in the first meter of depth. The soils are fine textured, sometimes calcareous, with low levels of organic matter. G and GT soil treatments showed higher organic matter content (on average 1.4%) than T (0.88%). Better root development (number and area) was observed in G and GT, in comparison with T; the number and size of roots showed a positive correlation with the soil organic matter.

Until a few years ago, pseudo-cereals and some other plants (originating either from Latin America or from Asia or Africa) of interest as food were almost unknown in Europe, but recently they have attracted the attention of researchers because of their growing diffusion in the agri-food industry. In the human diet, pseudo-cereals such as quinoa (Chenopodium quinoa Willdenow), amaranth (Amaranthus spp.) and buckwheat (Fagopyrum esculentum Moench) are appreciated for some properties including high nutritional values; similarly chia (Salvia hispanica L.), which is an oily seed, and teff (Eragrostis tef (Zuccagni) Trotter), which is instead a cereal, have interesting nutritional profiles. The grains of these plants can be consumed in the place of traditional cereals, as such or transformed into flour to obtain bread, pasta or other derivatives. Their cultivation is increasing in various countries of Europe, including Italy and, as for all (other) cereals, they are susceptible to attack by pests after harvest. This aspect cannot be ignored. Our laboratory research has investigated the susceptibility of pseudocereals, chia and teff to attack by some common stored-product beetles and moths known for their more or less marked polyphagy: Rhyzopertha dominica (F.) (Bostrichidae), Sitophilus granarius (L.) (Dryophthoridae), Tenebrio molitor (L.) (Tenebrionidae) and Plodia interpunctella (Hübner) (Pyralidae). Results revealed significant differences in the timescale and means of infestation and larval development: S. granarius and R. dominica grew only on buckwheat; P. interpunctella grew on all seeds except amaranth, with high larval trophic activity, but most larvae died between 60 and 90 days after the beginning of the infestation. T. molitor larval activity was observed on all the grains and the life cycle was not interrupted. This study, still underway, is a first step towards optimizing the storage methods of these new products and to understanding their main risks of in

Quinoa (Chenopodium quinoa Willd.) is a chenopodiaceous plant native to South America, cultivated for centuries mainly in Bolivia, Peru and Ecuador countries which together account for more than 80% of world production. This herbaceous plant has wide potential for use: in the human diet (both in grain form and as flour and derivatives), as animal feed, and also in non-food and industrial applications, although the main interest is the former, due to its nutritional qualities and because it is gluten free, not being a cereal. In recent years, cultivation has been undertaken in several European countries,including Italy, where quinoa is grown both in experimental plots and in open fields. The study of the insects found on this crop has been carried out above all in South America but also in the United States and, more recently, in some European countries, where experimental cultivation began several years ago. In Italy, where the spontaneous and closely related Chenopodium album L. is present, it is particularly interesting to investigate which insects adapt to feed on the new crop. It is very likely that quinoa attracts indigenous-weed insect pests. As part of the experimental agronomic tests carried out recently to verify the adaptability of quinoa to the territory of Piacenza and Pavia (northern Italy), surveys have been carried out on the insect pests of this plant. In 2016, three test fields of quinoa and one second-level variety comparison field were sampled, while in 2017 the sampling was carried out in four second-level variety comparison fields. The results obtained show that the crop is attacked in the early vegetative phases by aphids (Rhynchota Aphidoidea) and flea beetles (Coleoptera Chrysomelidae), while in the flowering phase until ripening the most harmful insects are bugs (Rhynchota Pentatomidae, Coreidae, Miridae). Attacks by flea beetles, if combined with particularly dry periods, can seriously compromise the crop.

Blattella germanica (L.) is a common pest of anthropic environments. Cockroach infestations are associated with poor sanitation, particularly around food-handling facilities, causing damages and contaminations. Furthermore, this species is responsible for transmitting microorganisms which implicate medical and hygienic problems. In this study, carried out in the framework of the European project "Ecosyn" (Ecofriendly synergists for insecticide formulations, funded by the 7th Framework Program of the European Union, contract no. 605740), the synergists PBO and some of its new derivatives were combined with two insecticides to assess any possible effect. The cypermethrin was assayed using a contact test in vials, leaving the insects with the products for 30 minutes, evaluating the knock-down effect every 5 minutes. Then, cockroaches were transferred in untreated vials and mortality was assessed 24 hours later. In general, the synergists did not influence the knock-down effect but caused a significant increase in mortality compared to the insecticide used alone. The S-methoprene effect was evaluated feeding virgin females for a week with moist baits containing insecticide and synergist. After mating with untreated males, every day mortality and appearance, abortion or hatching of ootheca were assessed. Although differences among various synergists were observed, the treated cockroaches showed a delay in ootheca production, an increase in its abortion and a reduction in the number of births.