Search

Scaphoideus titanus Ball (Hemiptera: Cicadellidae) is a major pest for European viticulture due to its high efficiency in the transmission of one of the most destructive pathogens for grapevine, namely flavescence dorée phytoplasmas. Although it plays a major role in spreading this disease, S. titanus is part of a complex epidemiological cycle involving several alternative vectors with variable relevance for phytoplasma spread. Here we provide an updated review on S. titanus monitoring and modelling, as well as the available tools for management of this pest and for limiting phytoplasma transmission and, thus, also spread. Insecticide-based control is examined; additional emphasis is placed on innovative and low-impact control approaches, such as vibrational mating disruption, biocontrol, and methods to reduce vector competence. We also discuss the main emerging challenges to the implementation of effective and sustainable control programs against S. titanus. [ABSTRACT FROM AUTHOR]

The family Pentatomidae (Hemiptera: Heteroptera) includes several invasive stink bug species capable to attack a large number of wild and cultivated plants, causing several damages to different crops. Pentatomids rely on obligate symbiotic associations with bacteria of the family Enterobacteriaceae , mainly of the genus Pantoea. A distinctive trait of these associations is the transmission route: during oviposition, females smear egg masses with symbiont-containing secretions, which are ingested by newly hatched nymphs, allowing the symbiont to pass through their digestive tract and establish in the crypts of the posterior midgut. Preventing newborns from orally acquiring symbionts seriously affects their fitness and survival. This symbiont inheritance process can be manipulated to develop innovative pest control measures by sterilization of egg masses prior to nymph hatching. This review summarizes the recent knowledge advances concerning the gut primary symbionts of pentatomids, with a specific focus on the most troubling pest species for agriculture. Current understanding of host colonization dynamics in pentatomids is presented, as well as the phenotypic effects determined in different insect species by the alteration of vertical transmission. Details on the current knowledge on the whole bacterial communities accompanying primary symbionts are analyzed. The recent research exploiting the perturbation of symbiont acquisition by pentatomid nymphs is discussed, by considering published work on laboratory and field trials with several active substances. These translational strategies are presently regarded as promising for limiting the populations of many important pentatomid pests in a sustainable way. [ABSTRACT FROM AUTHOR]

The brown marmorated stink bug Halyomorpha halys is an invasive Asiatic pentatomid recently introduced in Europe. It is regarded as a major pest of many crops due to its marked polyphagy, high reproduction potential and high mobility. Among European countries where H. halys established in the last years, most of economic losses have been reported in Italy. A promising control approach against H. halys is based on the suppression of its gut primary symbiont 'Candidatus Pantoea carbekii' (P. carbekii), vertically transmitted through maternal secretions containing symbiotic bacteria smeared during oviposition, which are ingested by neonates. Symbiont elimination is regarded as a promising pest control strategy based on the application of antimicrobial substances. Here, an anti-symbiont activity is shown in response to the application of micronutrient fertilizers showing antimicrobial activity, resulting in H. halys nymphal mortality under laboratory conditions. Exposure to commercial products, available for organic farming, was tested in combination with a pesticide additive on isolated stink bug egg masses, by measuring survival to II nymphal instar of neonates emerging from treated eggs. Zinc, copper and citric acid biocomplexes showed the most effective impact on H. halys survival, causing more than 90% nymph mortality. Molecular diagnosis for P. carbekii confirmed that observed effects were attributable to missed symbiont acquisition. Taken together, our results provide indication for the potential field use of micronutrient fertilizers as controls tool against H. halys. Future work will provide indications to maximize the effect of this approach in the field, enabling to design a new, eco-friendly approach for the control of this pest threatening Italian and European agriculture. [ABSTRACT FROM AUTHOR]

The biocontrol agent Torymus sinensis has been released into Japan, the USA, and Europe to suppress the Asian chestnut gall wasp, Dryocosmus kuriphilus. In this study, we provide a quantitative assessment of T. sinensis effectiveness for suppressing gall wasp infestations in Northwest Italy by annually evaluating the percentage of chestnuts infested by D. kuriphilus (infestation rate) and the number of T. sinensis adults that emerged per 100 galls (emergence index) over a 9-year period. We recorded the number of T. sinensis adults emerging from a total of 64,000 galls collected from 23 sampling sites. We found that T. sinensis strongly reduced the D. kuriphilus population, as demonstrated by reduced galls and an increased T. sinensis emergence index. Specifically, in Northwest Italy, the infestation rate was nearly zero 9 years after release of the parasitoid with no evidence of resurgence in infestation levels. In 2012, the number of T. sinensis females emerging per 100 galls was approximately 20 times higher than in 2009. Overall, T. sinensis proved to be an outstanding biocontrol agent, and its success highlights how the classical biological control approach may represent a cost-effective tool for managing an exotic invasive pest. [ABSTRACT FROM AUTHOR]

The embryonic and post-embryonic development ofScaphoideus titanus, the main vector of grapevine Flavescence dorée, was studied under laboratory conditions, at constant temperatures (T= 15, 18, 20, 22, 24, 27, and 29 °C). The data obtained were fitted to the equation of Brière, and the model was validated against independent field data. The minimum cardinal temperature for eggs ranged from 18 to 20 °C, the duration of egg hatching was minimum atT= 24 °C, egg hatchability was optimum at 22 °C, and very few eggs hatched atT≥ 27 °C. The duration of post-embryonic development clearly shortened as the temperature increased, both overall and within the same life stage, almost half-reducing itself from 18 to 29 °C. Within the same temperature tested, the early instars took less time to moult compared to the late ones. The data obtained provided a significant fit with the equation of Brière. Validation was satisfactory, particularly concerning third instar nymphs and adults, which are the key life instars for targeting integrated pest management (IPM) strategies. The model proposed could be used to predict the development ofS. titanusin north-western Italy for IPM purposes. [ABSTRACT FROM PUBLISHER]

Simple Summary: Investigations were conducted to evaluate the effectiveness of mating disruption (MD) to control chestnut tortrix moths. Surveys were performed at four sites in northern Italy in 2019–2020. MD was carried out using the pheromone dispenser Ecodian® CT. The total number of trapped males was significantly lower in MD plots than in control ones for all sites and years. Trap catch suppression in MD plots averaged 89.5% and 93.8% for Cydia fagiglandana and 57.4% and 81% for Cydia splendana in 2019 and 2020, respectively. A reduction of about 71% of larval infestation of chestnut fruits was only recorded in the MD plot at one site in 2019. Although the reduction in male catches in MD plots was observed, this research highlighted the need to perform further studies to investigate the effect of MD in reducing larval damage of chestnut fruits. (1) Background: Pheromone-based devices are successfully used to control insect pests in agriculture. (2) Methods: Investigations were conducted to evaluate the effectiveness of mating disruption (MD) to control the chestnut tortrix moths, Cydia fagiglandana and Cydia splendana. Surveys were performed in northern Italy in 2019–2020. MD was carried out using the pheromone dispenser Ecodian® CT. The effectiveness of MD was assessed by recording male adult catches in pheromone-baited sticky traps and larvae in chestnut fruits, comparing MD and control plots. (3) Results: The total number of trapped males was significantly lower in MD plots than in control ones, for all sites and years. Trap catch suppression in MD plots averaged 89.5% and 93.8% for C. fagiglandana and 57.4% and 81% for C. splendana in 2019 and 2020, respectively. The larval infestation rate in fruits did not vary between plots except for one site where a reduction of about 71% in the MD plot was recorded in 2019. (4) Conclusions: Low catches in MD plots turned out to be a good measure of the effectiveness of communication disruption, but no satisfactory data have been obtained regarding fruit infestation, highlighting how the reduction of male catches cannot always be considered as a reliable indicator of successful control. Specific investigations about background population density, dispersal and mating/oviposition behavior are thus essential for a viable management strategy. [ABSTRACT FROM AUTHOR]

Over the last 10 years, the use of nets to protect pome fruit from hailstorms has increased. In this study, we investigated the effect of these nets on the behavior of the codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), a major pest of apple, Malus domestica Borkh. (Rosaceae). Experiments were carried out in net-covered and uncovered apple orchards treated with conventional insecticides. The number of codling moth males caught in pheromone- and virgin female-baited traps was significantly reduced in net-covered compared to uncovered plots. In addition, inhibition of mating by the net was demonstrated by significant reductions in mating of tethered virgin females. Fruit injury was consistently lower in net-covered plots vs. uncovered plots. Because of the reductions in male trap catch, the reduced female mating frequency, and the lower level of damage, we conclude that flat anti-hail nets have a disruptive effect on the reproductive behavior of the codling moth. [ABSTRACT FROM AUTHOR]

Simple Summary: Mathematical models are developed to predict key aspects of insects harmful to many crops, including grapevine. Practical applications of these models include forecasting seasonal occurrence and spread over space in order to make decisions about pest management (e.g., timing of insecticide sprays). Many models have recently been developed to evaluate the spread of insect pests on grapevine under a climate change scenario as well as to forecast the possibility that alien species could settle into new environments. To make the published models available to vine-growers and their stakeholders, a holistic approach presenting these models within the frame of a decision support system should be followed. This paper reviews the existing predictive models concerning insects and mites harmful to grapevine. A brief conceptual description is given on the definition of a model and about different types of models: deterministic vs. stochastics, continuous vs. discrete, analytical vs. computer-based, and descriptive vs. data-driven. The main biological aspects of grapevine pests covered by different types of models are phenology, population growth and dynamics, species distribution, and invasion risk. A particular emphasis is put on forecasting epidemics of plant disease agents transmitted by insects with sucking-piercing mouthparts. The most investigated species or groups are the glassy-winged sharpshooter Homalodisca vitripennis (Germar) and other vectors of Xylella fastidiosa subsp. fastidiosa, a bacterium agent of Pierce's disease; the European grape berry moth, Lobesia botrana (Denis and Schiffermuller); and the leafhopper Scaphoideus titanus Ball, the main vector of phytoplasmas agents of Flavescence dorée. Finally, the present and future of decision-support systems (DSS) in viticulture is discussed. [ABSTRACT FROM AUTHOR]

Worldwide, organic farming is being promoted as one of the main alternatives to intensive conventional farming. However, the benefits of organic agriculture are still controversial and need to be tested across wide environmental gradients. Here, we carried out an observational study to test how agronomic practices, pest management, environmental impact and yield of conventional and organic vineyards changed along wide climatic and landscape gradients across Italy. We used a block design with 38 pairs of conventional and organic vineyards across Italy. Most agronomic practices did not differ between conventional and organic vineyards. By contrast, landscape composition and climate were strong predictors of management in both systems. First, increasing semi-natural areas around the vineyards reduced pesticide pressure and related environmental impacts, but was also associated with lower yield. Second, irrespective of the farming system, a warm and dry climate was associated with reduced fungicide pressure. Conventional farming had a yield gain of 40% in cold and wet climate compared to organic but the yield gap disappeared in the warmest regions. In both farming systems, we observed a large variability in management practices that was mainly explained by climate and landscape composition. This large variability should be considered when evaluating the benefits and drawbacks of different farming systems under contrasting environmental contexts. [Display omitted] • We compared conventional and organic vineyards along climate and landscape gradients. • Most agronomic practices did not differ between conventional and organic vineyards. • In both systems, climate and landscape were strong predictors of agronomic practices, pest management and yield. • Pesticide environmental impact decreased with increasing temperature and semi-natural areas in both systems. • Yield difference between organic and conventional farming depends on climate. [ABSTRACT FROM AUTHOR]