parasitism of the brown citrus aphid in dominica by lysiphlebus testaceipes and lipolexis oregmae hymenoptera aphidiinae

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Long-term monitoring and microbiological control programs against lepidopteran defoliators in Sardinian cork oak forests (Italy)

The gypsy moth, Lymantria dispar (L.), and the tent caterpillar, Malacosoma neustrium (L.), are the main cork oak, Quercus suber L., pests in the Mediterranean area and cause complete defoliation in large forest districts. In order to control infestations, large scale aerial applications of insecticides based on Bacillus thuringiensis subsp. kurstaki (Btk) have been carried out in Sardinia (Italy) since 2001. This paper evaluated the frequency of outbreaks in forest districts with varying homogeneity of land use, forest areas annually exposed to defoliation and the effectiveness of control programs based on Btk insecticide applications.The volume of areas annually exposed to defoliation depends on forest homogeneity, as infestations are more frequent in cork oak areas with a lower than 25% canopy cover rate. The microbiological control programme efficiently protected cork oaks from lepidopteran defoliators and caused an overall annual mean mortality of over 60%, with maximum rates of 89.9 and 98.0% for L. dispar and M. neustrium, respectively. To date, approximately 180,000 hectares of cork oak forests have been protected by spraying Btk-based insecticides

Sustainable management of the vine mealybug in organic vineyards

The vine mealybug (VMB), Planococcus ficus, is a major grapevine pest worldwide, whose chemical control is often unsatisfactory due to its cryptic behavior, insecticide resistance and high fecundity rate. Recently, increasing restrictions have been applied to insecticides used for managing VMB. This review discusses sustainable VMB management strategies in organic viticulture. Pheromone-mediated mating disruption has been proved to be effective in both organic wine and table-grape vineyards. Biocontrol projects carried out through the release of parasitoids and/or predators have often provided inconclusive results, ranging from effective reduction of mealybug infestation to a marginal impact of parasitoids on VMB density. The latter outcome is likely due to constraints affecting the parasitoid activity, such as the disrupting activity of mealybug-tending ants and broad-spectrum insecticides, or untimely release of parasitoids. Ant suppression should be associated with the release of beneficial organisms, as mealybug-tending ants can severely affect the parasitoid activity. Cultural and physical control and the employment of entomopathogens and natural products mitigate the buildup of VMB populations, but they are not widely applied. VMB control in organic viticulture requires the integration of different strategies, as application of single control tools as a stand-alone treatment may not be effective, especially for high pest infestation. Future research to determine the density action threshold below which sustainable methods are effective and calibrate efforts in relation with pest infestation is needed. A multi-disciplinary approach is required to define the most appropriate sustainable control protocols in different environmental conditions and promote a further spread of organic viticulture

Scientific and technological developments in mating disruption of scale insects

[EN] Mating disruption (MD) is a species-specific and environmentally friendly pest management tactic based on the release of synthetic sex pheromones aiming to interrupt the mate-finding communication and prevent mating in the target pest. The present work aims to provide an overview of the current scientific and technical knowledge on mating disruption of scale pests (Hemiptera: Coccoidea). Biparental scales are suitable targets for mating disruption (technically, MD is not suitable for parthenogenetic scales), as the females have a limited spreading ability, and adult males are short lived and have a narrow window of time for mate searching. In this perspective, delayed mating also plays an important role by reducing female attractiveness and population growth potential. The mechanisms involved in MD of scales are most likely assigned to `competitive disruption¿ rather than `noncompetitive¿ mechanisms, although no specific studies addressed this issue. Mating disruption has been commercially developed and increasingly applied against the vine mealybug Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae) and the California red scale Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae) to a lesser extent. Critical factors affecting MD effectiveness are the pest density and effective disruption late in the season. Mating disruption applied to scale pests is effective in small plots and compatible with biological control and integrated management programs. In conclusion, MD has a high potential for management of scale pests, providing that key factors such as technological advances in pheromone synthesis and pheromone formulations, elucidation of disruption mechanisms, and simplification of the registration process are addressed.The authors wish to thank Alejandro Carbonell and Teresa Gadea (EPA, Ecologia y Proteccion Agricola SL), Ignacio de Alfonso (Suterra LCC), David Haviland (University of California), and Vittorio Veronelli (CBC Europe) for providing insightful information on the application and spread of mating disruption. Funding was provided by Fundacao para a Ciencia e a Tecnologia I.P., Portugal, to Centro de Estudos Florestais (UIDB/00239/2020), and by the University of Catania in the framework of the research project `Emergent pests and pathogens and relative sustainable strategies -5A722192113'.Franco. José Carlos; Cocco, A.; Lucchi, A.; Mendel, Z.; Suma, P.; Vacas, S.; Mansour, R.... (2022). Scientific and technological developments in mating disruption of scale insects. Entomologia Generalis. 42(2):251-273. https://doi.org/10.1127/entomologia/2021/1220S25127342

INSECT PESTS OF EUCALYPTUSPLANTATIONS IN SARDINIA (ITALY)

In Sardinia (Italy), Eucalyptusplantations cover approximately 23,000 hectares, above all in the southern part ofthe island. There is a complex of phytophagous insect pests that is threatening the health status of Eucalyptustrees. Themost recent invasions include the sap-suckers, Glycaspis brimblecombei, Blastopsylla occidentalis, and the bronze bug,Thaumastocoris peregrinus. Other pest species have also been reported, including the gall wasps, Ophelimus maskelliand Leptocybe invasa, the longhorn beetles, Phoracantha semipunctataand P. recurva, and the weevils, Gonipterusscutellatusand Polydrusus(= Metallites) parallelus. Defoliation caused by the gypsy moth, Lymantria dispar, have alsobeen frequently observed in various Eucalyptus-planted areas of Sardinia

Osservazioni preliminari sul comportamento riproduttivo di Planococcus ficus e Planococcus citri (Hemiptera: Pseudococcidae)

No abstract availablePlanococcus citri (Risso) ha una modalit? di riproduzione tipicamente anfigonica e un sistema di determinazione del sesso basato sulla condensazione dell?assetto cromosomico di origine paterna nella linea maschile (Brown, 1966). Le osservazioni condotte su P. citri per verificare la possibilit? di riproduzione per partenogenesi sono contrastanti (Myers, 1932; Bodenheimer, 1951; Gray, 1954; Panis, 1969), mentre non risultano in letteratura indagini specifiche sulle modalit? di riproduzione di Planococcus ficus (Signoret). Queste informazioni assumono un?importanza fondamentale quando si intendono sperimentare tecniche di lotta, come la confusione sessuale o le catture massali di maschi, che possono risultare efficaci solo se la specie bersaglio si riproduce per via anfigonica. Viste anche le recenti sperimentazioni sulla lotta a P. ficus con la tecnica della confusione sessuale (Walton et al., 2006), si ? ritenuto utile condurre osservazioni sulla possibilit? di riproduzione partenogenetica delle due cocciniglie. A tal fine, per ciascuna specie, 300 neanidi di I-II et? sono state allevate singolarmente all?interno di contenitori in Plexiglas trasparente contenenti tre acini d?uva. I contenitori sono stati chiusi superiormente con tulle a maglie sufficientemente fitte da impedire l?ingresso dei maschi. Dalle neanidi di P. citri sono stati ottenuti 37 maschi e 40 femmine. Queste ultime, in assenza di accoppiamento, nel corso della loro vita adulta non hanno ovideposto; solo un individuo ha prodotto un abbozzo di ovisacco senza uova. Dalle neanidi di P. ficus sono stati ottenuti 86 maschi e 39 femmine. Questa specie ha mostrato la capacit? di riprodursi per partenogenesi. Infatti, pur non accoppiandosi, 9 femmine hanno deposto uova da cui sono sgusciate neanidi; altri 6 individui hanno formato solo ovisacchi privi di uova. Ulteriori studi sono in corso per verificare l?assenza di partenogenesi in P. citri e valutare il potenziale biotico di femmine partenogenetiche e fecondate in P. ficus

Climate and landscape composition explain agronomic practices, pesticide use and grape yield in vineyards across Italy

Context 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. Objective 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. Methods We used a block design with 38 pairs of conventional and organic vineyards across Italy. Results and conclusions 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. Significance 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

Control of <i>Tuta absoluta</i> (Meyrick) (Lepidoptera: Gelechiidae) in greenhouse tomato crops using the mating disruption technique

The effectiveness of mating disruption to control the tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), in greenhouse tomato crops was evaluated in four trials carried out in winter–spring and summer–winter growing seasons in Southwestern Sardinia (Italy). Pheromone dispensers loaded with 60 mg of the natural blend of the major and minor sex pheromone component (rate 90 : 10) were applied in disrupted greenhouses at a rate of 1000/ha (60 g of active ingredient/ha). Male captures in monitoring pheromone traps, percentage of tomato plants infested by T. absoluta and damage on leaves and fruits were monitored weekly and compared in disrupted and untreated (control) greenhouses. In greenhouses disrupted with 1000 dispensers/ha, a reduction of 93–97% in male trap captures was observed, compared with control. Leaf damage was significantly lower in greenhouses disrupted with 1000 dispensers/ha than in control ones, with a reduction of infestation throughout the growing season ranging from 57% to 85%. Pheromone dispensers applied at the density of 1000/ha significantly reduced the percentage of damaged fruits by 62–89%. In control greenhouses, the highest damage on leaves and fruits was generally observed in edge plants, while leaf and fruit infestation was uniformly distributed in pheromone-treated greenhouses, indicating an even distribution of the pheromone cloud inside the greenhouse. Mating disruption showed to be an efficient strategy to control in greenhouse the tomato leafminer and can be included in the overall tomato integrated pest management programs

Comparative development and reproduction of <i>Planococcus ficus</i> and <i>Planococcus citri</i> (Hemiptera: Pseudococcidae) on grapevine under field conditions

1. Mealybugs are major pests in grape-growing areas worldwide, causing direct and indirect crop damage. The vine mealybug Planococcus ficus (Signoret) is a key pest in most of grape-producing countries, whereas the citrus mealybug Planococcus citri (Risso) is reported as being destructive in Brazilian and Spanish vineyards. 2. We examined the adaptation of the citrus mealybug to grapevine by investigating its development, reproduction and life-history parameters under Mediterranean field conditions in comparison with those of P. ficus. 3. Both mealybug species developed and reproduced successfully on grapevine. However, P. ficus showed a shorter development time, larger female body size, and higher fecundity, fertility and survival than P. citri. 4. The life-history parameters further highlighted the different growth potential of vine and citrus mealybug populations because P. ficus exhibited a net reproductive rate and an intrinsic rate of increase two- to four-fold higher than that of P. citri. Furthermore, the vine mealybug population doubled its number in approximately half time with respect to the citrus mealybug. 5. Overall, the results of the present study show a better development and reproductive performance and a higher population growth potential of P. ficus compared with P. citri, indicating a higher capacity of the vine mealybug to develop on grapevine in Mediterranean vineyards