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Stink bugs pose a significant economic threat to legume crops globally. Our study aimed to evaluate the host weed plant preference of Piezodorus guildinii in common beans management and its susceptibility to Beauveria bassiana. Within those associated to P. vulgaris, four weed species were identified as hosts for P. guildinii. Although P. vulgaris was preferred, Sorghum halepense (L.) Pers. (Poaceae) showed lower preference. Among the weed hosts, Mimosa pellita (Hump. & Bonpl. ex Willd) (Mimosaseae) displayed a higher incidence (3.5 stink bugs/plant) of P. guildinii. Mortality induced by the native B. bassiana isolates Bb-51-SOE and Bb-15-SOM at 1 × 108 conidia mL−1 were significantly higher than the commercial strain peaked at 97.5% and 95%, respectively, after 8 days, with commercial strain Bb-18 achieving 72.5% mortality after 10 days. Median lethal concentration values (LC50) ranged from 1.04 × 106 to 9.7 × 107 conidia mL−1, with the Bb-51-SOE and Bb-15-SOM isolates showing the highest virulence, with median lethal time (LT50) values of 5.49 and 5.81 days, respectively. These findings provide important information on the ecology of P. guildinii in P. vulgaris cultivation and offer sustainable pest control alternatives, supporting integrated management programs in Cuba. [ABSTRACT FROM AUTHOR]

Several stink bugs species constitute an important pest complex in soybean worldwide. Tachinidae parasitoids are an important tool to be exploited in conservation biological control programs. We evaluated parasitism of pentatomids in different periods of their life-history: diapause (late autumn and winter), start of activity (spring) and full activity (late summer and early autumn). During the growing seasons 2017–2018 and 2019–2020, we collected stink bugs from soybean, alfalfa and wheat crops and natural vegetation, of three species (Nezara viridula, Edessa meditabunda and Diceraeus furcatus) and reared them in laboratory until pupal formation and adult emergence of tachinid. We examined the relationship among pentatomid abundance and multiple measures of parasitism: through observation of tachinid eggs externally attached to stink bugs body upon field collection and through further verification of parasitism in the laboratory. We also examined the preference of tachinids regarding host sex. Seven tachinid species were detected. Neobrachelia cf. edessae parasitizing E. meditabunda was recorded for the first time in Argentina. Only in two periods of N. viridula life history (diapause and start of activity period) the presence of tachinid eggs externally attached to the stink bugs cuticle was a reliable estimation of successful parasitism. Parasitism was highest on N. viridula, followed by E. meditabunda and lower on D. furcatus. Parasitism of stink bugs was highest during the start of activity and during diapause. During the full activity period in 2017–2018 male hosts were more parasitized than females. This work provides field results valuable for designing tools for pentatomid conservation biological control programs. [ABSTRACT FROM AUTHOR]

Currently, mirids, stink bugs and coreid bugs are the most important insect pests of cocoa in Ghana. The populations of these insect pests are known to be influenced by the availability of food and breeding sites, as well as the macro and micro climates in cocoa farms. The study investigated variations in the population dynamics of these pests and their damage trends within a square mile (259 hectares). Pest numbers and damage were assessed monthly on 100 trees per plot from 2015 to 2020, each plot measuring one acre (0.4 hectare). Significant differences (p < 0.05) were observed in pest numbers and damage symptoms of the different pest species for the various months of assessment. Populations of each pest species (mirids, stink bugs and the coreid bugs) and their associated damage in the various cocoa plots were significantly different (p < 0.05). The study showed that relying on the pest activity in one cocoa plantation to determine pest management activities in a nearby cocoa plot may not always lead to accurate and effective pest control. The need for pest surveillance and monitoring at the farm level as a basis to design effective Integrated Pest Management in cocoa production is discussed. [ABSTRACT FROM AUTHOR]

The objective of the present work was to implement integrated pest management (IPM) in the soybean crop, comparing it with the management carried out by the farmer during two consecutive seasons. The monitoring of adult lepidopterans was also evaluated using Delta-type traps baited with the sexual pheromones of Spodoptera frugiperda (Bio Spodotera®), Helicoverpa armigera (Bio Helicoverpa®) and Chrysodeixis includens (Bio Pseudoplusia®). Incidence of caterpillars and stinkbugs in soybeans was weekly determined, both in the IPM area and in the farmer, area using the beat cloth method. Insecticide applications in the IPM area were carried out when pest population densities reached the control level, while in the area managed by the farmer, sprayings were carried out at his discretion. Based on the results obtained, we found that adoption of IPM enabled better control of the pests in soybeans, especially for stink bugs, and the number of insecticide applications in soybeans could be reduced, which provides economic and environmental benefits for the farmer. In addition, we found that the sexual pheromones of the three evaluated pest species are effective in capturing their moths.

Soybean (Glycine max) is the world's most widely grown seed legume. One of the most important pests that decrease seed quality and reduce yield of soybean crops is the southern green stink bug (Nezara viridula). Insect damage triggers accumulation of defensive compounds such as protease inhibitors (PIs), isoflavonoids and reactive oxygen species, which are regulated by the lipoxygenase (LOX)-regulated jasmonic acid (JA) to stop insect feeding. This study identified and characterised the role of LOX isoforms in the modulation of chemical defences in seeds of field-grown soybean that decreased digestive enzyme activities of N. viridula after insect attack. Stink bugs attack increased LOX 1 and LOX 2 expression, and activities of LOX 1 and LOX 3 isoenzymes in developing soybean seeds. In addition, stink bug damage and methyl jasmonate application induced expression and activity of both cysteine PIs and trypsin PIs in developing soybean seeds, suggesting that herbivory induced JA in soybean seeds. High PI activity levels in attacked seeds decreased cysteine proteases and a-amylases activities in the gut of stink bugs that fed on field-grown soybean. We demonstrated that LOX isoforms of seeds are concomitantly induced with JA-regulated PIs by stink bugs attack, and these PIs inhibit the activity of insect digestive enzymes. To our knowledge, this is the first study to investigate the participation of LOX in modulating JA-regulated defences against stink bugs in seeds of field-grown soybean, and our results suggest that soybean PIs may inhibit a-amylase activity in the gut of N. viridula. [ABSTRACT FROM AUTHOR]

Tropical crops face significant challenges from abiotic and biotic stressors, resulting in substantial losses. This study aimed to assess the yield and losses in Bt soybean crops in Tocantins state, northern Brazil, during the 2017/2018 and 2018/2019 growing seasons. We monitored and estimated yield losses and their contributing factors in commercial fields, spanning dry and rainy seasons, from planting to harvest. Our findings revealed that crop yields remained consistent between the dry season (4349.85 kg/ha) and the rainy season (4206.51 kg/ha). Similarly, the overall yield loss showed no significant variation between seasons, with values of 902.86 kg/ha (dry) and 1007.92 kg/ha (rainy). Nevertheless, the factors contributing to these losses exhibited season-dependent variations. We observed higher plant mortality rates during the dry season, whereas insects (particularly stink bugs) and fungi were the primary contributors to grain yield losses during the rainy season. Conversely, losses due to flower abortion and pod malformation remained relatively consistent between the two seasons. Our study underscores the increase in soybean yield in one of Brazil's agricultural frontiers. While overall yield and losses remained stable between dry and rainy seasons, the distinct seasonal patterns influencing yield losses call for nuanced and season-specific strategies in sustainable crop management. [ABSTRACT FROM AUTHOR]

Euschistus stink bugs are important pests on soybean crops, including the Neotropical representatives Euschistus heros , Euschistus crenator, and Euschistus taurulus. Despite their importance, little genomic and chromosomal information is available. Genomic and chromosomal differences can play an important role in establishing reproductive barriers between species and populations. Here we investigate the chromosomes, some repetitive DNAs, and genome sizes of three Euschistus species, including two E. heros strains (North strain-NS and South strain-SS), to address chromosomal evolution and genomic differentiation. Our data reveal conservative karyotypes and only one possible inversion among Euschistus species. Moreover, we observe Y chromosome reorganization through differential microsatellite accumulation. The nuclear genome sizes are slightly variable among species. We noticed a differential accumulation of satellite DNAs, mainly on the Y chromosome, in the two strains of E. heros. Although typical meiotic behaviour, demonstrating full compatibility, was observed in hybrids despite interference on chiasmata frequency. This data shows that chromosomal and repetitive DNAs do not prevent secondary contact between E. heros strains, contributing to genetic variability in hybrids. Therefore, we provide data about Euschistus pests and their chromosomal characteristics, representing the first step in understanding their genomic organization and evolution. [ABSTRACT FROM AUTHOR]

Pentatomid bugs, commonly known as stink bugs, are typically herbivorous insects known for their piercing-sucking feeding habits on crops and wild plants. Among these stink bugs, Spermatodes variolosus (Walker, 1867) stands out as the smallest species, measuring 2.6-2.9 mm, and is also known to be phytophagous. In this study, we report the presence of seven species from six different genera of stink bugs in the rice fields of Cooch Behar, West Bengal. Notably, this research marks the first documented occurrence of Spermatodes variolosus (Walker, 1867) in the rice ecosystem of India, raising concerns about its potential pest status. Furthermore, this study includes taxonomic keys for the six genera identified.

Simple Summary: Today, we are faced with urbanization and growing urban environments. Therefore, the number of insect species in cities is decreasing. However, urban insect pests, particularly populations of invasive species, are not limited by the factors that limit native insect populations. This article aims to describe four scenarios of the successful spread of invasive species in urban areas. Two mosquitoes and two stink bug species were selected for this study: the Asian tiger mosquito, the Japanese bush mosquito, the brown marmorated stink bug, and the southern vegetable stink bug. Regardless, mosquito species are considered insects of medical importance and stink bugs cause significant damage to agricultural production. What these four species have in common is their role as nuisance pests in urban environments. Urban areas are often populated by specific species of insects, some colorful and appealing, such as ladybugs and butterflies, and others irritating as nuisance bitters or as vectors of pathogens of public health importance. Mosquitoes in urban areas often utilize habitats adjacent to human residences, while phytophagous insect species such as stink bugs often colonize ornamental plants and utilize human-made structures including houses as overwintering shelters. This article discusses the early detection and the current distribution of two invasive mosquito species, Aedes albopictus Skuse 1894 and Ae. japonicus (Theobald 1901), in Serbia, introduced in 2009 and 2018, respectively. From the first findings until today, regular monitoring has been carried out and the establishment of both species in the newly invaded areas has been confirmed. Both species can become nuisance species, especially at high population densities, but more importantly, they are capable of transmitting a wide variety of arboviruses of public health importance. This article also discusses two invasive stink bug species Halyomorpha halys Stål 1855 and Nezara viridula Linnaeus 1758, introduced in Serbia in 2015 and 2008, respectively. These two stink bug species have also been monitored, and the establishment of their populations in the country has been confirmed. Both species have caused damage to a wide range of crops and ornamental plants and sometimes become nuisance pests in urban areas. [ABSTRACT FROM AUTHOR]

Knowledge of the biology of a pest is essential for building sustainable management programmes. Pentatomidae have a hemimetabolous life cycle with egg, nymphal, and adult life stages, which differ in morphological, ecological, and behavioural traits. Some of these traits, such as mating behaviour, pheromones (alarm and aggregation pheromones) and the acquisition of gut symbionts can be targeted for pest management strategies. Here, we review the available literature on these life history traits of the Pentatomidae with potential for use in management programmes. Pheromone-mediated aggregation and the disruption of symbiont acquisition are two important targets for Pentatomidae control. Other traits such as the use of alarm pheromones for enhancing natural enemies and substrate-borne vibration for mating disruption deserve further consideration. Colour vision and flight ability are still poorly studied, despite their potential importance for stink bug management. [ABSTRACT FROM AUTHOR]

Diceraeus melacanthus Dallas, (Hemiptera: Pentatomidae) is a polyphagous stink bug that has been reported to be an important pest in maize and soybean. Control of this herbivore in crops is achieved using insecticides. Use of companion plants to control and manage herbivores in crop areas has been proposed, but there are still few systems that have been deployed to growers. Trap crops work by attracting herbivores, removing them from target plants, or/and attracting their natural enemies. Observations in our laboratory revealed that female D. melacanthus oviposit in Cajanus cajan L. Millsp (Fabaceae) pods. Therefore, the aim of this study was to evaluate whether C. cajan plants have potential for use as trap crops for D. melacanthus. In the current study, we evaluated the oviposition behaviour of D. melacanthus and its preference for different substrates, such as cotton bolls, C. cajan, Glycine max L. Merril (Fabaceae) and Phaseolus vulgaris L. (Fabaceae) pods; their behavioural response to constitutive volatiles emitted by C. cajan plants at different phenological stages; and the effect of non-volatile compounds of C. cajan pod on oviposition preference. The results revealed that D. melacanthus females prefer to oviposit on C. cajan pods, cotton bolls rubbed on C. cajan pods or cotton bolls treated with quercetin over cotton bolls and P. vulgaris pods. D. melacanthus females recognize and are attracted by volatiles of reproductive C. cajan plants. In addition to the preference for ovipositing, the offspring of D. melacanthus does not survive on C. cajan pods. Our results suggest that C. cajan plants have the potential to be evaluated as a trap crop for D. melacanthus. [ABSTRACT FROM AUTHOR]

Piezodorus guildinii (Westwood) (Hemiptera Pentatomidae) is an important pest of several crops. Biological control using parasitoids as natural enemies of pests represents a promising alternative strategy to the use of pesticides. Oophagous parasitoids are helpful in the management of this pest, but they are not sufficient for the control of the target insect. The aim was to assess the potential of a parasitoid of the adult stage of related stink bug species, Hexacladia smithii Ashmead (Hymenoptera Encyrtidae), as a biocontrol agent targeting P. guildinii. In the laboratory, adults of this stink bug were successfully parasitized, allowing also the emergence of a first filial generation of parasitoids. The percentage of emergence of wasps reached 61.9%. The results obtained indicate that H. smithii has the potential to develop in this host. This is the first record of H. smithii developing two generations on P. guildinii adults, indicating that this stink bug is a component of the host range of H. smithii. The action of parasitoids that attack the adult stage of hosts, such as H. smithii, in combination with the control exerted by the egg parasitoids, may be useful for the management of P. guildinii. [ABSTRACT FROM AUTHOR]

Urban areas are often populated by specific species of insects, some colorful and appealing, such as ladybugs and butterflies, and others irritating as nuisance bitters or as vectors of pathogens of public health importance. Mosquitoes in urban areas often utilize habitats adjacent to human residences, while phytophagous insect species such as stink bugs often colonize ornamental plants and utilize human-made structures including houses as overwintering shelters. This article discusses the early detection and the current distribution of two invasive mosquito species, Aedes albopictus Skuse 1894 and Ae. japonicus (Theobald 1901), in Serbia, introduced in 2009 and 2018, respectively. From the first findings until today, regular monitoring has been carried out and the establishment of both species in the newly invaded areas has been confirmed. Both species can become nuisance species, especially at high population densities, but more importantly, they are capable of transmitting a wide variety of arboviruses of public health importance. This article also discusses two invasive stink bug species Halyomorpha halys Stål 1855 and Nezara viridula Linnaeus 1758, introduced in Serbia in 2015 and 2008, respectively. These two stink bug species have also been monitored, and the establishment of their populations in the country has been confirmed. Both species have caused damage to a wide range of crops and ornamental plants and sometimes become nuisance pests in urban areas.

Simple Summary: An updated species checklist for all the Pentatomoidea species for Greece is provided. Eight species are recorded from Greece for the first time. The checklist is supported with distributional data notes for all the Pentatomoidea species of Greece. Eight species of the superfamily Pentatomoidea are recorded from Greece for the first time: Aelia germari Küster 1852, Eurygaster hottentotta (Fabricius 1775), Eysarcoris aeneus (Scopoli 1763), Neottiglossa lineolata (Herrich-Schaeffer 1830), Neottiglossa pusilla (Gallen 1789), Picromerus bidens (Linnaeus 1758), Podops (Podops) inunctus (Fabricius 1775) and Tarisa pallescens (Jakovlev 1871). A complete updated species checklist with distributional data notes for all the new species for Greece are provided. [ABSTRACT FROM AUTHOR]

BACKGROUND: Interspecific competition in insect parasitoids is an important ecological phenomenon that has relevant implications for biological pest control. To date, interspecific intrinsic (=larval) competition has been intensively studied, while investigations on extrinsic (=adult) competition have often lagged behind. In this study we examined the role played by parasitoid reproductive traits and host clutch size on the outcome of extrinsic competition between Trissolcus basalis (Wollaston) and Ooencyrtus telenomicida (Vassiliev), two egg parasitoids of the pest Nezara viridula (L). Laboratory experiments were conducted by allowing both parasitoid species to exploit an egg mass made of 10, 20, 30, or 40 hosts through single or simultaneous releases. Furthermore, under field conditions, egg masses consisting of 10 or 40 hosts were exposed in a tomato crop in order to validate laboratory investigation. RESULTS: The results show that the egg mass size is an important predictor of extrinsic competition in our study system as a higher proportion of T. basalis emerged from large egg masses, while O. telenomicida dominated in small egg masses. Analysis of reproductive traits of parasitoid species indicates that T. basalis has superior abilities in host exploitation compared with O. telenomicida. CONCLUSIONS: We found that contrasting reproductive traits of two competing egg parasitoid species facilitate coexistence on a shared stink bug host. This work also highlights the importance to consider extrinsic competitive interactions between parasitoid species in a biological control perspective. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Knowledge of the biology of a pest is essential for building sustainable management programmes. Pentatomidae have a hemimetabolous life cycle with egg, nymphal, and adult life stages, which differ in morphological, ecological, and behavioural traits. Some of these traits, such as mating behaviour, pheromones (alarm and aggregation pheromones) and the acquisition of gut symbionts can be targeted for pest management strategies. Here, we review the available literature on these life history traits of the Pentatomidae with potential for use in management programmes. Pheromone-mediated aggregation and the disruption of symbiont acquisition are two important targets for Pentatomidae control. Other traits such as the use of alarm pheromones for enhancing natural enemies and substrate-borne vibration for mating disruption deserve further consideration. Colour vision and flight ability are still poorly studied, despite their potential importance for stink bug management.

The role of generalist predators has long been considered an important component of mortality for many agricultural pests but can be difficult to quantify. We present the use of digital imaging as a means of both identifying key stink bug egg predators and measuring their relative impact on egg survivorship. Brown marmorated stink bug (BMSB), Halyomorpha halys and bagrada bug, Bagrada hilaris, two exotic stink bugs new to California, are now widely distributed throughout the state. A survey was conducted to identify resident natural enemies of their eggs. A field camera aided in the identification of arthropods attacking these eggs and their relative impact. Predation of BMSB eggs, which are naturally oviposited onto plant foliage, was less than for eggs of bagrada bug, which oviposit onto and into soil. The top ranked predators of BMSB eggs were the carabid Laemostenus complanatus (Coleoptera) the European earwig Forficula auricularia and ring-legged earwig Euborellia annulipes (Dermaptera), the oriental cockroach Blatta orientalis (Orthoptera), and the spider Trachelas spp. (Araneae). The two most common and important predators of bagrada bug were two ant species (Formicidae), Solenopsis xyloni and Monomorium ergatogyna, and species of Collembola (Entomobryidae). A Predation Index was developed to compare the relative importance of BMSB egg predators. Lastly, two striking, unanticipated results are reported: an apparent synergistic interaction between the spider Trachelas spp. and native ant M. ergatogyna in causing damage to sentinel eggs of BMSB, and the predaceous role for Collembola on bagrada bug sentinel eggs. [ABSTRACT FROM AUTHOR]

Background: Herbivorous insects are one of the main biological threats to crops. One such group of insects, stink bugs, do not eat large amounts of tissue when feeding on soybean, but are damaging to the quality of the seed yield as they feed on green developing seeds leading to poorly marketable harvests. In addition to causing physical damage during sucking-feeding activities, the insects can also transmit microbial pathogens, leading to even greater yield loss. Conducting surveys of the insect intestinal microbiome can help identify possible pathogens, as well as detail what healthy stink bug digestive systems have in common. Methods: We used the conserved V4 region of the 16S rRNA gene to characterize the bacterial microbiome of the red-banded stink bug Piezodorus guildinii collected in Brazil and the United States, as well as the neotropical brown stink bug Euschistus heros collected in Brazil. Results: After quality filtering of the data, 192 samples were kept for analyses: 117 samples from P. guildinii covering three sites in Brazil and four sites in the United States, and 75 samples for E. heros covering 10 sites in Brazil. The most interesting observations were that the diversity and abundance of some bacterial families were different in the different ecoregions of Brazil and the United States. Conclusion: Some families, such as Acetobacteraceae, Bacillaceae, Moraxellaceae, Enterobacteriaceae, and Rhodocyclaceae, may be related to the better adaptation in some localities in providing nutrients, break down cellulose, detoxify phytochemicals, and degrade organic compounds, which makes it difficult to control these species. [ABSTRACT FROM AUTHOR]

BACKGROUND: Using plant‐based extracts and their constituents has been suggested as an alternative tool to replace or integrate with the synthetic compounds used to manage insect pests. Here, we evaluated the potential of extracts obtained from Ficus carica Linn (Moraceae) branches and leaves against the Neotropical brown stink bug, Euschistus heros, one of the most prevalent insect pests in soybean fields. We further isolated and evaluated the toxicity of the extracts' major components against E. heros. Additionally, by using computational docking analysis and toxicological approaches, we assessed the physiological basis for the selectivity of these extracts against beneficial insects such as pollinator bees (i.e. Apis mellifera and the Neotropical stingless bee Partamona helleri), ladybeetles (Eriopis connexa and Coleomegilla maculata), and lacewings (Chrysoperla externa). RESULTS: Our results demonstrate that branch (LC50 = 5.9 [4.7–7.1] mg mL–1) and leaf (LC50 = 14.1 [12.5–15.4] mg mL–1) extracts exhibited similar toxicity against E. heros. Our phytochemical analysis revealed psoralen and bergapten furanocoumarins as the major components of the extract. Based on our computational predictions, these molecules' differential abilities to physically interact with the acetylcholinesterases of E. heros and beneficial insects play relevant roles in their selectivity actions. The estimated LC90 values of branch (30.0 mg mL–1) and leaf (30.0 mg mL–1) extracts killed less than 12% of the beneficial insects. CONCLUSION: Overall, our findings revealed that furanocoumarin‐rich extracts obtained from F. carica extracts have the potential to be used as alternative tools in the integrated management of stink bug pests. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]