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BACKGROUND: Exotic ambrosia beetles are emerging widespread pests of several wild and managed trees and shrubs. Xylosandrus compactus (Eichhoff) is one of the most invasive species causing damage to a broad range of host plants. Little information is available on its control, including the impact of insecticides. Bioassays were conducted to evaluate the potential of four bioinsecticides and seven synthetic insecticides in controlling X. compactus. Beetle mortality and sublethal effects on tunneling, cultivation of the mutualist fungus and reproduction were assessed. RESULTS: Concentration–mortality curves were determined for all tested insecticides. Lambda‐cyhalothrin was the most toxic insecticide, showing the lowest estimated 90% and 50% lethal concentrations (LC90 and LC50), followed by deltamethrin and thiamethoxam. Acetamiprid caused the highest levels of mortality and brood size reduction under extended laboratory conditions. Moreover, acetamiprid, thiamethoxam and lambda‐cyhalothrin caused the greatest mortality and, together with deltamethrin, strongly affected progeny occurrence inside infested galleries and beetle brood size. Among the bioinsecticides, pyrethrins significantly affected beetle survival under laboratory conditions, but not brood size in extended laboratory bioassays. Some of the tested insecticides had significant lethal and sublethal effects only when beetles were exposed to fresher residues, highlighting differences in toxicity persistence. CONCLUSION: This study provides first baseline toxicity data for synthetic insecticides and bioinsecticides with different modes of action and origin toward X. compactus, and the first evidence that several insecticides can cause multiple sublethal effects on this pest. These findings can help in building suitable integrated pest management packages against this pest. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Plants developed a series of defence mechanisms to counteract the attack of herbivores. These can impact on food‐webs at various trophic levels, in both natural and managed ecosystems, such as crops. The biochemical and ecological bases behind these processes are reviewed here by highlighting the differences in direct and indirect, constitutive and induced defences. In integrated pest management (IPM), several pest control tools are applied in an economically sound way in order to increase the crop resilience and reduce reliance on synthetic pesticides. Plant resistance is thus a crucial aspect of preventive pest control strategies in several agroecosystems, including tomato. In this context, we review the current literature dealing with the physiology and biochemistry of tomato plants in terms of metabolite pathways and multitrophic interactions. We also describe recent advances in plant defence‐based control tools obtained by studying the multitrophic interactions between pests and plants in the tomato system. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), has recently invaded Yili region in Xinjiang, China. In this region, sex pheromone-based control techniques are considered promising components of integrated pest management programs. However, the potential parthenogenesis and polygyny of T. absoluta may affect the effectiveness of these techniques. In the first part of this study, the parthenogenetic reproduction potential of females collected from Yili was assessed. Consistent with French and Tunisian populations, these females were also able to reproduce parthenogenetically. However, the Yili population had a much lower capacity to produce viable offspring in F1. Next, the effects of a biased T. absoluta sex ratio on offspring density, and tomato plant damage and growth were evaluated. With the exception of the combination 4F+0M (F: female adult; M: male adult), tomato plants infested by 4F+1M, 4F+2M, 4F+3M, and 4F+4M yielded similar quantities of offspring (larvae + pupae) in F1, which indiscriminately affected plant damage and growth. Overall, compared with parthenogenetic reproduction, polygyny in the Yili population of T. absoluta is likely to undermine the effectiveness of sex pheromone-based control techniques in this region. Therefore, growers should be cautious about relying on sex pheromone-based management techniques. [ABSTRACT FROM AUTHOR]

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) also known as spotted-wing drosophila (SWD), is a pest native to Southeast Asia. In the last few decades, the pest has expanded its range to affect all major European and American fruit production regions. SWD is a highly adaptive insect that is able to disperse, survive, and flourish under a range of environmental conditions. Infestation by SWD generates both direct and indirect economic impacts through yield losses, shorter shelf life of infested fruit, and increased production costs. Fresh markets, frozen berries, and fruit export programs have been impacted by the pest due to zero tolerance for fruit infestation. As SWD control programs rely heavily on insecticides, exceedance of maximum residue levels (MRLs) has also resulted in crop rejections. The economic impact of SWD has been particularly severe for organic operations, mainly due to the limited availability of effective insecticides. Integrated pest management (IPM) of SWD could significantly reduce chemical inputs but would require substantial changes to horticultural management practices. This review evaluates the most promising methods studied as part of an IPM strategy against SWD across the world. For each of the considered techniques, the effectiveness, impact, sustainability, and stage of development are discussed. Graphical Abstract [ABSTRACT FROM AUTHOR]

The spotted wing drosophila, Drosophila suzukii Matsumura (Diptera: Drosophilidae), is an invasive pest native to Asia that has recently invaded Europe and the Americas. This pest can seriously compromise fruit production in infested crops and has a remarkable ability to invade new areas with a diverse range of environments. We report for the first time D. suzukii infestations in African crops. We sampled 101 fields cultivated with soft-skinned fruits in two regions of northwestern Morocco. Morphological and molecular analyses confirmed the occurrence of D. suzukii in this area. In 2017 and 2018, approximately 15% of the surveyed farms growing small berries were infested by D. suzukii. A total of 61.11% of the surveyed raspberry fields were infested, followed by blueberries (22.22%), strawberries (11.11%) and mulberries (5.56%). Peak infestations were between March and June and in November and December. We carried out preliminary mass trapping in a raspberry tunnel, and of the two traps used, the red-colored trap baited with baker's yeast and sugar was the most effective. The results are discussed in the light of the invasion potential for the African continent and integrated pest management (IPM) perspectives for soft fruit production in Morocco. [ABSTRACT FROM AUTHOR]

Background: Bemisia tabaci (Hemiptera: Aleyrodidae) represents one of the greatest threats to agricultural crops. Chemical control is the primary tool used in integrated pest management (IPM) programs. However, release of the predator Nesidiocoris tenuis (Hemiptera: Miridae) on tomato plants is a highly recommended control tactic. The objective of this study was to evaluate the efficacy of a commercial borax plus citrus oil (BCO) product against B. tabaci in the presence and absence of N. tenuis. The synthetic insecticide lambda‐cyhalothrin was used as a positive control. We also evaluated the sublethal effects of BCO on the behavior and predation rate of N. tenuis. Results: Our results demonstrated that BCO, alone and at its maximum recommended field rate for B. tabaci, was not effective in controlling the pest under laboratory conditions. Application of BCO simultaneous with N. tenuis release did not reduce the increase in the B. tabaci population. Effective control of B. tabaci was achieved using only N. tenuis. However, synthetic lambda‐cyhalothrin pyrethroid, used here as a control, caused high pest mortality and led to on‐site extinction of N. tenuis, which did not occur for insects exposed to BCO. Lambda‐cyhalothrin and BCO significantly affected the foraging behavior of N. tenuis, reducing the predation rate, especially following exposure to lambda‐cyhalothrin. Conclusion: The insecticide lambda‐cyhalothrin achieved satisfactory results in suppressing B. tabaci, but was harmful to N. tenuis. Additionally, lambda‐cyhalothrin and BCO affected predator behavior. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The combined use of chemicals and biological control is not always a successful strategy owing to the potential side effects on biocontrol agents. Lethal and sublethal effects of three commonly used insecticides were assessed on adult and immature stages of the egg parasitoid Trichogramma brassicae Bezdenko (Hymenoptera: Trichogrammatidae). Recommended field concentrations of chlorantraniliprole, phosalone and spinosad caused mortality on preimaginal stages by 24, 87, and 98%, respectively. Lethal effects on parasitoid adults exposed to the insecticide dry residues were estimated as median lethal concentrations (LC50) that were 13.28, 0.25, and 0.03 µg a.i. ml−1 for chlorantraniliprole, phosalone, and spinosad, respectively. The effect of a low lethal concentration (LC30) of the compounds was evaluated on various adult biological traits, such as longevity, fecundity, emergence rate and other life table parameters. All compounds caused detrimental effects on all the estimated demographical indexes. Chlorantraniliprole affected the net reproductive rate, mean generation time and doubling time in comparison to the control; while, phosalone and spinosad adversely affected all assessed parameters. Phosalone and spinosad significantly reduced gross reproductive rate, net reproductive rate, intrinsic rate of increase, finite rate of increase, mean generation time and doubling time and reduced longevity, fecundity, emergence rate related to other biological parameters in comparison with control. The results suggest that all compounds are not fully compatible with the activity of T. brassicae, and that the inclusion of chlorantraniprole, spinosad and phosalone into Integrated Pest Management (IPM) involving this parasitoid has to be avoided. Nevertheless, further studies in open field conditions and on a multiple generation scale are necessary for providing a more definitive conclusion on the IPM suitability of the three tested insectcides. [ABSTRACT FROM AUTHOR]

BACKGROUND Encarsia formosa Gahan is the most important parasitoid exploited for the control of whitefly pests of vegetable crops. However, the non‐target effects of recently developed insecticides for controlling whiteflies toward this biocontrol agent is little documented. Here we evaluated the susceptibility of E. formosa adults and juveniles to eight commonly used insecticides against whiteflies. RESULTS: Residual toxicity tests on glass showed that E. formosa adults were susceptible (over 98% mortality after 6 h treated) to field concentrations of the tested neonicotinoids (imidacloprid, acetamiprid, nitenpyram and thiamethoxam), abamectin, cyantraniliprole, and sulfoxaflor at their field concentrations. Pyriproxyfen was harmless to both adult and pupae of E. formosa. A risk quotient analysis showed that toxicity of pyriproxyfen to E. formosa adults was the lowest, followed by acetamiprid and cyantraniliprole. In the leaf residues test, mortality of E. formosa adults under all insecticides decreased when the residue age increased. Interestingly, E. formosa experiencing contact with the residues of most insecticides, except pyriproxyfen and abamectin, parasitized significantly more hosts 5‐days after treatment, suggesting a hormetic effect on parasitism. CONCLUSION: The risk assessment of insecticides indicated that pyriproxyfen and cyantraniliprole were the least toxic to E. formosa. Our results suggest that the inclusion of the insecticides in sustainable integrated pest management programs of whiteflies should be carefully evaluated on a case‐by‐case basis. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Since its initial detection in Turkey in 2009, the invasive destructive pest South American tomato pinworm Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) has started its new invasion journey to east and invaded most Asian countries. This pest currently causes extensive damage to tomato production and potentially threatens key production areas such as China. To provide an overview of current status of T. absoluta in Asia, we have briefly reviewed the damage and economic impacts by this pest locally and discussed why this species has spread so rapidly among the countries. Moreover, ongoing integrated pest management options are summarized in newly invaded areas with an emphasis of discussing the potential control failures by chemical insecticides. Future research efforts on developing promising management technologies are recommended. Finally, we suggest building a cross-regional network to enhance the sustainable control of this pest. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is an invasive destructive pest of tomato and other solanaceous plants. Since its first detection in Spain in 2006, the pest has started its invasion across the Afro-Eurasian supercontinent. Xinjiang Uyghur Autonomous Region of China, adjacent to the recently infested central-Asia countries, being the largest tomato growing region worldwide, is now under high invasion risk. Considering the importance of this issue, we must plan ahead to be fully prepared for the potential invasion of this pest in near future. In this paper, we call for upcoming studies to address several aspects including the overwintering biology, diapause, dispersion, population ecology in outdoor crops and insecticide resistance of invading populations. Moreover, the effective management options are proposed based on the control experience in its native range and recently infested countries. Our "look-ahead" proposal not only serves as a guideline for elaborating the pest management strategy in Xinjiang in near future, but can also interest the rest of the tomato-producing regions worldwide that have not been infested yet by the moth. [ABSTRACT FROM AUTHOR]

Highlights from the article: Invasive arthropod pests hold great socio-economic and ecological importance, in the current global agricultural scenario (Paini et al. [16]). Following the I T. absoluta i arrival in European countries, various integrated pest management packages mainly based on monitoring, biological control and use of selective insecticides have been developed and implemented (Biondi et al. [5]). 1Tomato leaflet with mines caused by Tuta absoluta larvae (left), tomato fruit infested by T. absoluta larvae (center), T. absoluta adult on tomato a leaf (right). 9 Desneux N, Luna MG, Guillemaud T, Urbaneja A. The invasive South American tomato pinworm, Tuta absoluta, continues to spread in Afro-Eurasia and beyond: the new threat to tomato world production.

The Asian vinegar fly Drosophila suzukii (spotted wing Drosophila [SWD]) has emerged as a major invasive insect pest of small and stone fruits in both the Americas and Europe since the late 2000s. While research efforts have rapidly progressed in Asia, North America, and Europe over the past 5 years, important new insights may be gained in comparing and contrasting findings across the regions affected by SWD. In this review, we explore common themes in the invasion biology of SWD by examining (1) its biology and current pest status in endemic and recently invaded regions; (2) current efforts and future research needs for the development of predictive models for its geographic expansion; and (3) prospects for both natural and classical (=importation) biological control of SWD in invaded habitats, with emphasis on the role of hymenopteran parasitoids. We conclude that particularly fruitful areas of research should include fundamental studies of its overwintering, host-use, and dispersal capabilities; as well as applied studies of alternative, cost-effective management techniques to complement insecticide use within the integrated pest management framework. Finally, we emphasize that outreach efforts are critical to effective SWD management by highlighting successful strategies and insights gained from various geographic regions. [ABSTRACT FROM AUTHOR]

During the years after the invasion of Western Palaearctic tomato crops by the South American tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), several indigenous generalist parasitoids have been recorded on this new host. Among these, Bracon nigricans Szépligeti (Hymenoptera: Braconidae) is widely distributed in the Palaearctic region, and has been frequently recovered from South American tomato leafminer. However, most of the available data on this species deal with taxonomic aspects and its recovery in faunistic surveys. The current study documents the biology of B. nigricans on South American tomato leafminer, and provides a scientific basis for its inclusion in South American tomato leafminer management programs in Afro-Eurasia. We studied several B. nigricans life-history traits relevant to juvenile development and reproduction by females. B. nigricans proved to be an idiobiont and a synovigenic ectoparasitoid of mature South American tomato leafminer larvae. Several B. nigricans reproductive traits were influenced by the age of the mothers; on average, the progeny had a slightly male-biased sex ratio (60% males) and a low rate of successful development (≈37%). Adult females lived 42.8 d and produced an average of 29.8 offspring. These biological parameters yielded an intrinsic rate of increase of 0.052. Females showed behavioral plasticity in host use, as initial host paralysis was followed by host-feeding, oviposition, or host rejection, with a consequent high mortality rate among hosts exposed to parasitism. Although further field studies are needed, these data, obtained in laboratory conditions, suggest that B. nigricans should be considered as a potential biological control agent of in newly invaded areas of the Palaearctic region. [ABSTRACT FROM AUTHOR]

Abstract: The generalist predator Orius laevigatus (Fieber) (Hemiptera: Anthocoridae) is a key natural enemy of various arthropods in agricultural and natural ecosystems. Releases of this predator are frequently carried out, and it is included in the Integrated Pest Management (IPM) programs of several crops. The accurate assessment of the compatibility of various pesticides with predator activity is key for the success of this strategy. We assessed acute and sublethal toxicity of 14 pesticides on O. laevigatus adults under laboratory conditions. Pesticides commonly used in either conventional or organic farming were selected for the study, including six biopesticides, three synthetic insecticides, two sulfur compounds and three adjuvants. To assess the pesticides’ residual persistence, the predator was exposed for 3d to pesticide residues on tomato sprouts that had been treated 1h, 7d or 14d prior to the assay. The percentage of mortality and the sublethal effects on predator reproductive capacity were summarized in a reduction coefficient (Ex ) and the pesticides were classified according to the IOBC (International Organization for Biological Control) toxicity categories. The results showed that the pesticides greatly differed in their toxicity, both in terms of lethal and sub lethal effects, as well as in their persistence. In particular, abamectin was the most noxious and persistent, and was classified as harmful up to 14d after the treatment, causing almost 100% mortality. Spinosad, emamectin, metaflumizone were moderately harmful until 7d after the treatment, while the other pesticides were slightly harmful or harmless. The results, based on the combination of assessment of acute mortality, predator reproductive capacity pesticides residual and pesticides residual persistence, stress the need of using complementary bioassays (e.g. assessment of lethal and sublethal effects) to carefully select the pesticides to be used in IPM programs and appropriately time the pesticides application (as function of natural enemies present in crops) and potential releases of natural enemies like O. laevigatus. [Copyright &y& Elsevier]

Simple Summary: The coccinellid Harmonia axyridis is an important natural enemy of various agricultural pests, including aphids. Agrochemicals can negatively affect the performance of arthropod natural enemies and, thus, the ecological services they provide. In this context, we assessed the lethal and sublethal effects of two neuroactive compounds with different chemical structures: the long-established neonicotinoid insecticide, imidacloprid, and the novel, sulfoximine insecticide, sulfoxaflor, both of which act on nicotinic acetylcholine receptors against adult and developmental stages of H. axyridis. Estimated LC20 and LC50 doses of imidacloprid for a target pest species, Aphis gossypii, resulted in significantly greater mortality in contact bioassays against adult H. axyridis compared with equivalent LC20 and LC50 doses of sulfoxaflor. Both concentrations of imidacloprid and sulfoxaflor significantly reduced the proportion of ovipositing females of parental generation. LC20 and LC50 dose of imidacloprid and LC50 dose of sulfoxaflor significantly reduced both the fecundity and fertility of parental generation. In progeny of parents exposed to both insecticides at LC50 concentrations the juvenile survival rate was significantly reduced, and both concentrations of imidacloprid and sulfoxaflor, except LC20 dose of sulfoxaflor, significantly prolonged the larval development time. These experimental results disclose the negative influence of sulfoxaflor and imidacloprid at low concentrations on the harlequin ladybird and its subsequent generation. Hence, actions should be taken to optimize imidacloprid and sulfoxaflor applications for the control of aphid pests, aiming at preserving the biocontrol services provided by this important predator. The harlequin ladybird, Harmonia axyridis Pallas (Coleoptera: Coccinellidae), is a generalist predator and an effective biocontrol agent of various insect pests that has been exploited for the control of aphid pests in the greenhouse and field. However, insecticides are widely used to control aphid pests worldwide and the potential non-target effects of sulfoxaflor and imidacloprid for controlling aphid pests towards this biocontrol agent are little known. Although both sulfoxaflor and imidacloprid act on nicotinic acetylcholine receptors of insects, sulfoxaflor has a novel chemical structure compared with neonicotinoids. We assessed the lethal, sublethal and transgenerational effects of sulfoxaflor and imidacloprid on H. axyridis simultaneously exposed via ingestion of contaminated prey and via residual contact on the host plant at LC20 and LC50 doses estimated for the cotton aphid. Imidacloprid significantly reduced the survival of H. axyridis adults compared to sulfoxaflor at the same lethal concentration against cotton aphid. Both concentrations of imidacloprid and sulfoxaflor reduced the proportion of ovipositing females, and both concentrations of imidacloprid and sulfoxaflor, except LC20 dose of sulfoxaflor, reduced the fecundity and fertility of the parental generation. In the progeny of imidacloprid- and sulfoxaflor-exposed parents, both tested LC50 concentrations significantly decreased the juvenile survival rate, and both concentrations of imidacloprid and sulfoxaflor, except LC20 dose of sulfoxaflor, prolonged the development time. Our findings provide evidence of the negative influence of imidacloprid and sulfoxaflor at low lethal concentrations on the harlequin ladybird and on the progeny of exposed individuals, i.e., transgenerational effects. Hence, these findings stress the importance of optimizing the applications of imidacloprid and sulfoxaflor for the control of aphid pests, aiming at preserving the biocontrol services provided by H. axyridis throughout the integrated pest management approach. [ABSTRACT FROM AUTHOR]

The efficacy of natural enemies in controlling pests under field conditions is largely correlated with their capacity to spread within infested crops. In this study the spatial dispersal of the California red scale parasitoid Aphytis melinus DeBach (Hymenoptera: Aphelinidae) was evaluated in the field after augmentative releases. The experiment was conducted in 2007 in six 1-ha plots in a Sicilian citrus orchard under integrated pest management. A total of 180,000 A. melinus adults was released in each of three plots and the other plots were left as untreated control. The flight range of the parasitoid was evaluated, for 35 days after the release, on 16 trees per each plot, located at 20 and 40 m from the central release point using yellow sticky traps activated with Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae) sexual pheromone and by monitoring the percentage parasitism of the scale on fruits and twigs. The effects of the distance from the release point and density of susceptible stages of host on parasitoid dispersal were evaluated. The number of wasps captured during the whole trial was greater in the traps located 20 m from the release point than in those at 40 m and in the control plots. Aphytis melinus dispersed over distances less than 40 m based on both the lower percentage parasitism and numbers captured recorded at distances of 40 m. The results are discussed in the context of the biological control of California red scale in citrus orchards by means of wasp releases. In particular, the release points should be no more than 40 m apart for a quick and homogeneous colonization of the area treated. [ABSTRACT FROM AUTHOR]