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Agricultural production and crop yields are threatened around the world by the emergence and spread of agronomical pests, including diseases, insects, and weeds. Due to changes in precipitation, carbon dioxide levels, and warming temperatures being experienced throughout most of the world, new challenges are emerging for pest management in virtually all major cropping systems. While precise environmental impacts due to climate change are impossible to predict, they will require innovative and new solutions for pest management. In this article, we explore the challenges of 3 problem pest species with soybean: Johnsongrass, kudzu bug, and charcoal rot. Understanding pest responses to climate change is vital for better understanding the new agricultural innovations that will be required to manage them in the future. [ABSTRACT FROM AUTHOR]

Simple Summary: Invasive pests tend to move gradually to new areas from the initial location at which they were established or identified. Halyomorpha halys (Stål) and Megacopta cribraria (Fabricius) are two exotic invasive pests currently in the United States. Halyomorpha halys can damage various field crops such as soybean and corn and many species of fruits and vegetables, while M. cribraria attacks only soybean and the weed species kudzu. Halyomorpha halys and M. cribraria are a serious threat to soybeans, one of the major crops grown in Tennessee and in other southeastern states in the US. This research was focused on determining the establishment and seasonal abundances of H. halys and M. cribraria in soybeans in the central region of Tennessee in areas with few or no previous sightings of the two pests at the time of planning this study. Our results showed that both the H. halys and M. cribraria were established in the study locations, and the H. halys could become a serious pest during the pod-filling stage in September. The importance of monitoring these invasive pests in new areas with susceptible host plants to find their spread, establishment, and abundance is discussed. Halyomorpha halys (Stål) and Megacopta cribraria (Fabricius) are two exotic invasive pests that have invaded the United States in recent years. Halyomorpha halys can damage various fruits, vegetables, and field crops, such as soybean and corn, while Megacopta cribraria only attacks soybean and kudzu, a weed species. They are currently found in southeastern states and threaten soybean and other crops grown in the region. This study evaluated the seasonal abundance of H. halys and M. cribraria in soybeans in 2016 and 2017 in two counties in the central region of Tennessee, where both species had either a few sightings or none that were recorded when this research was being planned. Lures and sweep sampling were used to monitor H. halys, and sweep sampling was used to monitor M. cribraria. Halyomorpha halys was first detected in samples in late July. Their numbers increased in early to mid-September, reached the economic threshold in late Sept, and then started to decline. Megacopta cribraria was first detected in mid to late July, increased their populations in September, but did not reach the economic threshold and declined mid-October. Our results showed the seasonal abundances of H. halys and M. cribraria and their establishment in the central region of Tennessee. [ABSTRACT FROM AUTHOR]

This is the first study that examined and compared the survival, LC50, and RR50 estimates of Megacopta cribraria F. (Hemiptera: Plataspidae) nymphs and adults that were exposed to two native Beauveria bassiana isolates (Previously codified as NI8 and KUDSC strains) at four concentrations. The greatest reduction in survival and mortality was observed primarily on or after 10 d post-exposure to B. bassiana isolates. Survival of early instars (2nd, 3rd) were not affected by either strains or concentration at 3 d and 5 d post-exposure. Survival of later instars (5th) and adults was significantly reduced when exposed to the KUDSC strain at all concentrations. Comparison of dose–mortality values (LC50) using resistance ratios (RR50) were significantly different between life stages of the kudzu bug for both strains of B. bassiana. The LC50 values showed that kudzu bug adults are more susceptible than any other life stage when exposed to either strain. The KUDSC strain was more pathogenic than NI8 10 d after exposure, but NI8 exhibited significantly higher pathogenicity than KUDSC 20 d after exposure. Our results suggest potential field application of B. bassiana for kudzu bug control and their integration into pest management strategies to suppress them before they cause economic damage to soybean crops. [ABSTRACT FROM AUTHOR]

Abstract Many species interactions are dependent on environmental context, yet the benefits of obligate, mutualistic microbial symbioses to their hosts are typically assumed to be universal across environments. We directly tested this assumption, focusing on the symbiosis between the sap‐feeding insect Megacopta cribraria and its primary bacterial symbiont Candidatus Ishikawaella capsulata. We assessed host development time, survival, and body size in the presence and absence of the symbiont on two alternative host plants and in the insects' new invasive range. We found that association with the symbiont was critical for host survival to adulthood when reared on either host plant, with few individuals surviving in the absence of symbiosis. Developmental differences between hosts with and without microbial symbionts, however, were mediated by the host plants on which the insects were reared. Our results support the hypothesis that benefits associated with this host–microbe interaction are environmentally contingent, though given that few individuals survive to adulthood without their symbionts, this may have minimal impact on ecological dynamics and current evolutionary trajectories of these partners. OPEN RESEARCH BADGES This article has earned an Open Data Badge for making publicly available the digitally‐shareable data necessary to reproduce the reported results. The data is available at https://doi.org/10.5061/dryad.kg4bc56

This is the first study that examined and compared the survival, LC50, and RR50 estimates of Megacopta cribraria F. (Hemiptera: Plataspidae) nymphs and adults that were exposed to two native Beauveria bassiana isolates (Previously codified as NI8 and KUDSC strains) at four concentrations. The greatest reduction in survival and mortality was observed primarily on or after 10 d post-exposure to B. bassiana isolates. Survival of early instars (2nd, 3rd) were not affected by either strains or concentration at 3 d and 5 d post-exposure. Survival of later instars (5th) and adults was significantly reduced when exposed to the KUDSC strain at all concentrations. Comparison of dose–mortality values (LC50) using resistance ratios (RR50) were significantly different between life stages of the kudzu bug for both strains of B. bassiana. The LC50 values showed that kudzu bug adults are more susceptible than any other life stage when exposed to either strain. The KUDSC strain was more pathogenic than NI8 10 d after exposure, but NI8 exhibited significantly higher pathogenicity than KUDSC 20 d after exposure. Our results suggest potential field application of B. bassiana for kudzu bug control and their integration into pest management strategies to suppress them before they cause economic damage to soybean crops.

Megacopta cribraria (F.) (Hemiptera: Plataspidae) is an invasive pest of soybean that has spread across the southeastern United States since its initial discovery in 2009 in Georgia. Previous studies in the southeastern states have documented both the population dynamics of this pest and host plant resistance (HPR) among soybean varieties, although the specific mechanisms of HPR remain unknown. The objectives of this study were, therefore, to 1) quantify field resistance to M. cribraria in multiple soybean varieties in two states previously affected by severe M. cribraria infestations, North Carolina (NC) and South Carolina (SC); and 2) study the role of soybean trichome density in imparting resistance against M. cribraria. Soybean variety 'Camp' was least attractive to M. cribraria , through time and locations, suggesting consistent resistance. Other varieties showed variable performance among the locations and sampling dates. A significant difference in trichome density was evident. However, there was no correlation between trichome density and M. cribraria infestation. Compared to a previously published study in the same location, when M. cribraria adults emerging from overwintering dispersed into soybeans, in our study only first-generation adults dispersed into soybeans. Considering the current trend of significantly lower M. cribraria infestation rates in North and South Carolina, this pest may be finally succumbing to indigenous natural enemies and should be managed by incorporating integrated pest management tactics, such as HPR, that help conserve natural enemy populations. [ABSTRACT FROM AUTHOR]

The mass rearing of hymenopteran egg parasitoids requires an abundant supply of host eggs. The onset of reproductive diapause and subsequent decline in egg production poses a challenge for parasitoid rearing when using host colonies augmented by field-collected insects. We investigated the application of pyriproxyfen, a juvenile hormone analog, to induce oviposition in diapausing adult kudzu bugs, Megacopta cribraria (Fabricius) (Heteroptera: Plataspidae), and the use of eggs produced by pyriproxyfen-treated kudzu bugs to rear the egg parasitoid, Paratelenomus saccharalis (Dodd) (Hymenoptera: Scelionidae). The effects of pyriproxyfen and photoperiod treatments on host mortality, egg production, and rates of parasitoid eclosion from the eggs were used to calculate the parasitoid yield for the different treatment regimes. A combination of pyriproxyfen and a long-day photoperiod increased the parasitoid yield by 87% compared to acetone and a long-day photoperiod. The general applicability of JH-analog mediated egg production for parasitoid rearing is discussed.

Paratelenomus anu Rajmohana, Sachin & Talamas, sp. nov. (Hymenoptera: Scelionidae) is an egg parasitoid of the kudzu bug, Megacopta cribraria (Fab.) (Hemiptera: Plataspidae). It is morphologically and genetically distinct from P. saccharalis (Dodd), a well-known egg parasitoid of the same host. Paratelenomus anu is here described from India and diagnosed from other species of Paratelenomus Dodd. This parasitoid can be reared easily, has high rates of parasitism, and thus may be significant for the biological control of M. cribraria. Phoresy is documented in P. anu and provides the first known example of this behavior in Paratelenomus. Paratelenomus longus (Kozlov & Lê) syn. nov. and P. mangrovus Rajmohana & Narendran, syn. nov. are treated as junior synonyms of P. tetartus (Crawford), and P. obtusus (Lê) syn. nov. is treated as a junior synonym of P. saccharalis. [ABSTRACT FROM AUTHOR]

Many species interactions are dependent on environmental context, yet the benefits of obligate, mutualistic microbial symbioses to their hosts are typically assumed to be universal across environments. We directly tested this assumption, focusing on the symbiosis between the sap‐feeding insect Megacopta cribraria and its primary bacterial symbiont Candidatus Ishikawaella capsulata. We assessed host development time, survival, and body size in the presence and absence of the symbiont on two alternative host plants and in the insects' new invasive range. We found that association with the symbiont was critical for host survival to adulthood when reared on either host plant, with few individuals surviving in the absence of symbiosis. Developmental differences between hosts with and without microbial symbionts, however, were mediated by the host plants on which the insects were reared. Our results support the hypothesis that benefits associated with this host–microbe interaction are environmentally contingent, though given that few individuals survive to adulthood without their symbionts, this may have minimal impact on ecological dynamics and current evolutionary trajectories of these partners. OPEN RESEARCH BADGES: This article has earned an Open Data Badge for making publicly available the digitally‐shareable data necessary to reproduce the reported results. The data is available at https://doi.org/10.5061/dryad.kg4bc56 [ABSTRACT FROM AUTHOR]

During our study on egg parasitoids of the kudzu bug in Florida, we collected egg masses of Megacopta cribraria on kudzu and catnip for laboratory rearing. We found a new egg parasitoid, Ooencyrtus nezarae on M. cribraria, which represents the first Florida record of this parasitoid species. The wasp is widely distributed in Asia, and it will strengthen biological control of the kudzu bug in Florida. Future studies will assess comparative parasitism levels of Paratelenomus saccharalis and O. nezarae, as well as the dynamics of populations of these biological control agents. [ABSTRACT FROM AUTHOR]

Highlights • Environmental space anisotropy and niche unfilling cause non-adaptive niche shift. • Non-adaptive niche shift does not necessarily challenge transferability of SDMs. • Misuse of PAs can lead to misestimate of interpolation and transferability of SDMs. Abstract Transferability of species distribution models (SDMs) is key to predicting invasion patterns and can be challenged if niche shift occurs in the invaded range. When using native occurrences to estimate potential invasions with presence-only modeling methods, it is important to constrain the pseudo-absence (PA) sampling to the species' native range. However, some studies including highly cited ones, do not follow this approach to selecting PA samples. In this research, we addressed two questions using an invasive species in the United States (U.S.), kudzu bug (Megacopta cribraria): 1) is model transferability challenged by a non-adaptive niche shift? and 2) is model performance affected by use of PA samples from outside the native range of the species? Kudzu bug is native to Asia, with recently observed non-adaptive niche shift in the U.S. To answer the first question, we quantified the environmental space anisotropy and non-adaptive niche change, and then evaluated the performances of seven SDMs. To answer the second question, we further compared the interpolation and transferability of seven SDMs trained with PAs from the native range and from both native and invaded ranges. We confirmed that the environmental space anisotropy (P = 0.01) and non-adaptive niche change (P = 0.01) are both statistically significant. Of the seven SDMs used, four models had transferability indices higher than 0.9. Boosted regression tree and random forests both had good interpolation and transferability (AUC>0.80 and kappa>0.60), whereas three other models showed good interpolation and fair transferability (AUC>0.70 and kappa>0.40). Inclusion of pseudo-absences from the invaded range significantly increased the interpolation (P < 0.001) but decreased the transferability (P < 0.01) of almost all models. Our findings suggest that SDMs can show good transferability with non-adaptive niche shift, thus native occurrence information should be used in similar situation. We confirmed that it is crucial to constrain the PAs to the same spatial range as presences to accurately model potential invasions. [ABSTRACT FROM AUTHOR]

The kudzu bug, Megacopta cribraria (F.) (Heteroptera: Plataspidae), is an invasive pest of soybeans in the southeastern United States. Two greenhouse choice assays evaluated crop species and growth stage-specific orientation preference of kudzu bug adults to six different legume species (Fabales: Fabaceae) at four plant growth stages (V2, V4, R1, and R5). Adults had differential orientation to both legume species and plant growth stages tested. Adults preferred the R1 stage of soybean (Glycine max (L.) Merrill) and lima bean (Phaseolus lunatus (L.)), but preferred various growth stages of the other legumes tested. Given their respective attractive growth stages, adults significantly preferred lima bean (47.8%) to soybean (21.9%) and kidney bean (Phaseolus vulgaris (L.), 19.2%), and preferred mung bean (Vigna radiata (L.) Wilczek, 4.2%), black-eyed pea (Vigna unguiculata subsp. unguiculata (L.) Walp, 4.7%), and green bean (Phaseolus vulgaris (L.), 2.7%) the least. In no-choice assays, females deposited a similar number of eggs on each legume species, except for green bean and kidney bean, on which they deposited the fewest eggs. Eggs laid by females feeding on soybean (67.9%), lima bean (58.1%), and mung bean (42.6%) had significantly greater hatch rates than eggs laid by females feeding on the other legume species. No-choice assays also showed that nymphs completed development to adults on soybean, lima bean, and mung bean; yet, survival was greatest on soybean. Results show that females fed and oviposited on all of the legume species tested; however, plant species significantly affected egg hatch rates and nymphal survival. [ABSTRACT FROM AUTHOR]

The kudzu bug, Megacopta cribraria (F.) (Heteroptera: Plataspidae), is an invasive insect pest introduced from Asia in 2009 that poses a threat to soybeans (Glycine max [L.] Merr. [Fabales: Fabaceae]) and other legume crops in the United States. Initially discovered in Georgia, M. cribraria rapidly expanded across the southeast until 2014 when a significant decline in its population was observed across many locations. This notable decline in M. cribraria populations is attributed to the emergence of new parasitoids and pathogens in its new invasive range. So far, only a single egg parasitoid, Paratelenomus saccharalis (Dodd) (Hymenoptera: Platygastridae), is known to parasitize the eggs of M. cribraria in the United States. Here, we report a new egg parasitoid of M. cribraria identified as Ooencyrtus nezarae Ishii, 1928 (Hymenoptera: Encyrtidae), recovered from egg masses of M. cribraria collected from soybean in Alabama. O. nezarae is reported to parasitize eggs from a variety of heteropteran families and has been observed parasitizing M. cribraria in China. To the best of our knowledge, this is the first report of O. nezarae in North America. The potentials of O. nezarae for biological control of M. cribraria in the United States and the direction of future studies are discussed. [ABSTRACT FROM AUTHOR]

Kudzu bug, Megacopta cribraria Fabricius (Hemiptera: Plataspidae), first discovered in the United States in 2009, is an invasive pest of soybeans. From 2013 to 2016, Maryland has been the northern limit of its distribution in the United States. We sought to determine the physiological cold temperature limits, timing of movement to overwintering locations, and to characterize overwintering microhabitat temperature. We measured supercooling point (SCP) on three populations from distinct USDA plant hardiness zones in Maryland and Virginia between October and December of 2015. The average SCP across all sample months and populations was -12.6°C and no consistent trend of month or population location were observed. Additionally, we assessed the lower lethal temperature to kill 50% of the population (LLT50) at the same population locations in October and November 2015. The average LLT50 over both months and all three population locations was -5.1°C. Again, no consistent trend based on population location was observed but we did find a modest depression in the LLT50 values between October and November. We observed that kudzu bug overwinters in leaf litter and begins to move into the litter in late November to early December. Leaf litter moderates day to night temperature differences and was warmer than ambient temperature by an average of 0.7°C. Evidence suggests that the cold tolerance of the kudzu bug limits its distribution north of Maryland. [ABSTRACT FROM AUTHOR]

We conducted a field study to determine seasonal egg parasitism rates of the kudzu bug Megacopta cribraria (F.) on the kudzu plant, Pueraria montana (Lour.) Merr. var. lobata (Willd.) Maesen et Almeida ex Sanjappa and Pradeep, in Tokyo, Japan, during the period from May 2014 to September 2014. The eggs of M. cribraria per 1 m2 of kudzu at four locations in Tokyo were collected weekly and parasitism rates were assessed. Eggs of M. cribraria were laid on the kudzu plant from May to September. Megacopta cribraria eggs were parasitized by two parasitoid species, Paratelenomus saccharalis (Dodd) and Ooencyrtus nezarae Ishii. Paratelenomus saccharalis first appeared in May, and its parasitism rates peaked in July and September. Ooencyrtus nezarae first appeared in June and its parasitism rates peaked in July. Except for one location which could not be statistically analyzed because of the small sample size, occurrence of parasitism by P. saccharalis and O. nezarae in M. cribraria egg masses was independent at one location and positively associated at two locations, suggesting that the use of host egg masses by P. saccharalis and O. nezarae is not mutually exclusive. Parasitism rates by P. saccharalis and O. nezarae were significantly lower for egg masses parasitized by both species than for those parasitized by a single species. The proportion of males among O. nezarae progeny was significantly higher for egg masses parasitized by O. nezarae together with P. saccharalis than for those parasitized by O. nezarae alone. These results suggest that parasitism of host egg masses by the two species is influenced by their interspecific interactions. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Economic Entomology is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Megacopta cribraria (F.), an invasive species introduced from Asia in 2009, is now prolific in the southeastern United States. Megacopta cribraria develops primarily on kudzu and soybean completing two generations. It is not well understood how this economic pest is affected by changes in geographic distribution in the United States or how population levels have changed since its establishment. The effect of insecticide application timing on field populations of M. cribraria is not well documented. These studies seek to understand how population dynamics of M. cribraria vary with geographic regions in Georgia. Effect of application timing on populations throughout the growing season was also examined. Weekly from 2012 to 2013, all life stages were enumerated from kudzu and soybean environments at several locations throughout Georgia from sweeps samples and flight intercept captures. Coordinates were recorded for locations, and classified as belonging to the Piedmont or Coastal Plain region of the state. Single spray trials were conducted from2011-2014, and applications were made to soybean at intervals throughout the season. From2012 to 2015, two kudzu patches near Griffin, GA, weremonitored to detect population changes. Differences in population dynamics from locations around the state were found, but no clear effect of latitude, longitude, or region was observed. Insecticide applications applied in July suppressed nymph populations significantly better than treatments made earlier or later. Megacopta cribraria populations declined in 2014 and 2015 compared with 2012 and 2013. These studies provide the critical information for M. cribraria management in soybean in the southeastern United States. [ABSTRACT FROM AUTHOR]

Initially discovered in Georgia in 2009, the exotic invasive plataspid, Megacopta cribraria (F.), has become a serious pest of soybean (Glycine max (L.) Merrill). Managing M. cribraria in soybean typically involves the application of broad-spectrum insecticides. Soybean host plant resistance is an attractive alternative approach; however, no commercial soybean cultivars have been identified as resistant. During 2013 and 2014, we compared 40 and 44 soybean genotypes, respectively, for resistance to M. cribraria in a split-plot design under natural insect infestation in small-plot experiments. Soybean genotypes were selected to maximize diversity with respect to maturity group, pubescence type, leaf shape, seed size, nitrogen fixation, drought tolerance, seed protein content, and pest resistance. Megacopta cribraria egg masses, nymphs, and adults were counted during the growing season to identify potentially resistant soybean genotypes. Soybean seed yield was measured in insecticide-protected and unprotected conditions to determine tolerance to M. cribraria feeding. In both years, a range of host plant resistance was observed. The fewest M. cribraria adults and nymphs were found on narrow-leaf, small-seeded cultivars 'N7103' and 'Vance,' as well as the nonnodulating cultivar 'Nitrasoy.' Additionally, N7103 and Vance were among the least susceptible genotypes to M. cribraria oviposition in the field. Most 'Benning' cultivar insect-resistant near-isogenic breeding lines also displayed moderate levels of resistance to M. cribraria. Seed yields of Vance and N7103 were less affected by M. cribraria in 2013 than most other soybean genotypes. These results may be useful to soybean breeders to develop cultivars with resistance to M. cribraria. [ABSTRACT FROM AUTHOR]

The invasive plataspid Megacopta cribraria (F.) is now distributed throughout much of the southeastern United States. While it readily feeds and develops on the invasive weed kudzu, Puereria montana (Loureiro) Merrill var. lobata (Willdenow), M. cribraria is an economic pest of soybean, Glycine max (L.) Merrill. Differences in the susceptibility of soybean to M. cribraria-induced yield reductions based on plant phenology were assessed using two experimental protocols in Georgia, North Carolina, and South Carolina from 2011 to 2013 in which soybeans were protected from M. cribraria using insecticides during different stages of plant phenology. In the first protocol, where insecticide applications were initiated at progressively later stages in soybean development depending on treatment, yields in the untreated plots were reduced by an average of 13% compared with plots that were protected beginning at full flowering (R2). Soybean plots that were protected beginning at 4wk after full flowering or earlier did not suffer yield reductions from M. cribraria. In the second protocol, where insecticide applications began at R2 and were discontinued at progressively later stages in soybean development depending on treatment, yields in the untreated plots were reduced by an average of 12% compared with plots that were protected until 8wk after R2. Plots in which protection was discontinued beginning at 4wk after full flowering or later did not suffer yield reductions. The period from two to 6 wk after R2 (generally coinciding with pod and seed development - stages R3-R5) was identified as critical for management of M. cribraria. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Economic Entomology is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Prewinter copulation, sperm storage, and oocyte development in overwintering adult Megacopta cribraria (F.) was examined in Alabama (Lee Co.). Microscopic examinations of the spermathecae and ovaries were made in females and of the testes in males that were collected approximately weekly from September 2013 through March 2014. The results indicated that approximately 15% of females mated before entering winter dormancy and sperm was stored in their spermatheca for up to seven months, oocytes in mated overwintering females proceeded to postblastoderm stage before the onset of spring feeding and mating in March, all of the overwintering males had sperm in their testes, and the ratio of females gradually increased in populations during overwintering. This study indicates that both males and females are capable of reproductive dormancy. The biological significance of these life cycle aspects is discussed from the viewpoints of invasiveness and adaptation. [ABSTRACT FROM AUTHOR]

The plataspid Megacopta cribraria (F.), an economic pest of soybeans, Glycine max (L.) Merrill, in Asia recently invaded North America and has become not only an important pest of soybean but also a nuisance pest. Although much is reported about M. cribraria in its native and invasive range, little information has been documented on the effect of temperatures on its development, longevity, and reproduction. We evaluated the influence of five constant temperatures (17-33°C) on the development, survival, fecundity, and population growth of M. cribraria in the laboratory. The developmental time for egg and nymph stages was shortened significantly with increasing temperature. The developmental time from egg to adult emergence was 114.81, 76.26, 44.54, and 38.54 d at 17, 21, 25, and 29°C, respectively. The nymphs of M. cribraria could not complete full development at a constant 33°C. The developmental threshold temperature estimated for egg to adult was 14.25°C, with a thermal constant of 849.56 degree- days. Females had the longest preoviposition period at 21°C (54.33 d), and the preoviposition period was shortened significantly as the temperature increased. Females had the longest oviposition period (35.33 d) and the highest fecundity (159.67 eggs per female) at 25°C and did not lay any eggs at 17°C. Female longevity was found to be shortest (44.0 d) at 29°C, and similar (75.67-81.50 d) at 17-25°C. The population trend index of M. cribraria was the highest (46.47) at 25°C, followed by 29°C (10.84) and 21°C (6.70). The results will be useful for predicting the phenology and population dynamics of M. cribraria and will provide some biological information on the invasive species in its nonnative range. [ABSTRACT FROM AUTHOR]

The kudzu bug, Megacopta cribraria (F.) (Hemiptera: Plataspidae), is a newly invasive exotic insect found primarily on kudzu, but also on soybean, in the southeastern United States. We used molecular gut-content analysis to document predation on this pest by insects and spiders in soybean, and to detect remains of crop-specific alternative prey in predators' guts as markers of predator migration between soybean and adjacent cotton. M. cribraria was found exclusively on soybean. Eight native generalist predators over both crops screened positive by specific PCR for DNA of the pest: Geocoris punctipes (Say), Geocoris uliginosus (Say), Orius insidiosus (Say), Podisus maculiventris (Say), Hippodamia convergens Guérin-Méneville, Zelus renardii (Kolenati), Oxyopes salticus Hentz, and Peucetia viridans (Hentz); a ninth predator, the exotic Solenopsis invicta Buren, also screened positive for M. cribraria DNA. P. viridans was the only arthropod that tested positive for DNA of this invasive pest in only one crop, cotton. Two plant-feeding pentatomid species, Piezodorus guildinii (Westwood) and Thyanta custator (F.), were found exclusively on soybean, and another, Euschistus tristigmus (Say), was specific to cotton in the context of this study. Detection of predation on a combination of M. cribraria and P. guildinii and T. custator in cotton and M. cribraria and E. tristigmus in soybean demonstrated that these predators dispersed between crops. These results strongly support the use of soybean habitats adjacent to cotton as part of a conservation biological control strategy against M. cribraria. This is the first report documenting predation on this exotic pest in the field via molecular gut-content analysis. [ABSTRACT FROM AUTHOR]

The kudzu bug or bean plataspid, Megacopta cribraria (Fabricius), is native to Asia where it appears to be widely distributed (although the taxonomy is not entirely clear), but is infrequently a pest of legumes. This bug appeared in 2009 in the southeastern United States, where it is closely associated with kudzu, Pueraria montana Lour. [Merr.] variety lobata [Willd.] Maesen & S. Almeida. However, the insect has become a consistent economic pest of soybeans, Glycine max (L.) Merr., and some other leguminous crops in areas where large numbers can build in kudzu, in addition to being a considerable nuisance in urban landscapes where kudzu occurs. The insect has remarkable capacity for movement and has spread rapidly from nine Georgia counties in 2009 to seven states in 2012. Despite being a nuisance in urban areas and a crop pest, high populations of the bug also reduce the biomass of kudzu, which is itself a seriously problematic invasive weed, complicating the status of M. cribraria in its expanded range. Extant predators and a pathogen in the US have been observed attacking kudzu bugs in the laboratory and field, but no parasitism of eggs or nymphs has been observed to date. A single record of parasitism of an adult kudzu bug by a tachinid fly is known from the US, but no other adult parasitism has been observed in the US or elsewhere. Extant enemies may eventually significantly reduce the bug's populations, but at present native enemies appear to be insufficient for the task, and exotic enemies from the kudzu bug's native range may offer the best possibility for effective biological control in the US. Based on the available literature, the best option for an importation biological control program appears to be the platygastrid egg parasitoid Paratelenomus saccharalis (Dodd) because of its apparent host specificity, intimate biological linkages with M. cribraria, and wide geographic distribution in the Eastern Hemisphere. Other natural enemies may eventually emerge as good candidates for importation, but at present P. saccharalis appears to be the most promising. [ABSTRACT FROM AUTHOR]

The bean plataspid, Megacopta cribraria (F.), recently was discovered in the United States feeding on kudzu, Pueraria montana Lour. (Merr.) variety lobata (Willd.), an economically important invasive vine. We studied its biology on kudzu and its impact on kudzu growth. We also tested its ability to use other common forest legumes for oviposition and development. Flight intercept traps operated from 17 May 2010 to 31 May 2011 in a kudzu field near Athens, GA showed three peaks of adult flight activity suggesting there are two generations per year on kudzu. Vine samples examined for eggs from April 2010 to April 2011 and June to October 2011 showed two periods of oviposition activity in 2010, which coincided with the peaks in adult activity. In 2011, the second period of oviposition began on or before 24 June and then egg abundance declined gradually thereafter until late August when we recovered <2 eggs/0.5 m of vine. Samples of the five nymphal instars and adults on vines did not show similar trends in abundance. Adults did not lay eggs on the various legume species tested in 2010 in a no-choice test possibly because the cages were too small. In the 2011 field host range experiments conducted in a kudzu field by using 12 legume species, M. cribraria preferentially oviposited on kudzu over soybean, Glycine max Merrill., but they still laid 320 eggs per plant on soybean. Lespedeza hirta (L.) Hornem. and Lespedeza cuneata (Dum. Cours.) G. Don had 122. and 108.4 eggs per plant, respectively. Kudzu and soybean were the only species M. cribraria completed development on. Plots protected from M. cribraria feeding by biweekly insecticide applications had 32.8% more kudzu biomass than unprotected plots. Our results show that M. cribraria has a significant impact on kudzu growth and could help suppress this pest weed. [ABSTRACT FROM AUTHOR]

Megacopta cribraria (F.) (Hemiptera: Plataspidae) is a newly invasive, exotic pest of soybean ( Glycine max [L.] Merr.; Fabales: Fabaceae) in the southeastern United States. In 2013, the exotic egg parasitoid Paratelenomus saccharalis (Dodd) (Hymenoptera: Platygastridae) was discovered parasitizing eggs of this pest in kudzu ( Pueraria montana var. lobata [Willd.] Maesen & S. Almeida; Fabales: Fabaceae) and soybean in 3 states in this region of the United States. We evaluated parasitism of M. cribraria egg masses by P. saccharalis in conventional tillage and no-till organic soybean experimental plots in 2013. Density of M. cribraria egg masses was significantly higher in conventional tillage soybean than in no-till soybean in weeks 2 through 5 for the 7 wk period M. cribraria egg masses were detected on soybean. Percentage of parasitism of M. cribraria egg masses by P. saccharalis was significantly higher in conventional tillage soybean (58.4%) than in no-till soybean (44.9%). In general, parasitism rates of egg masses were higher in conventional tillage soybean, where M. cribraria egg mass density was higher, than in no-till soybean. [ABSTRACT FROM AUTHOR]

Simple Summary: Rearing of many hymenopteran egg parasitoids requires a reliable supply of host eggs. The parasitoid Paratelenomus saccharalis can be reared on eggs produced from field collected kudzu bug, Megacopta cribraria, however field-collected hosts obtained during reproductive diapause do not readily produce eggs and must be reared under a long day-length photoperiod to terminate diapause. In this study we found that an exogenous application of pyriproxyfen was able to terminate diapause, leading to a significant increase in egg production. The eggs produced by pyriproxyfen-treated M. cribraria were accepted by the egg parasitoid Paratelenomus saccharalis, however parasitoid emergence was reduced when compared to eggs from untreated hosts. When the effects of pyriproxyfen treatment on egg production and parasitoid emergence were evaluated together, the net increase in parasitoid yield due to pyriproxyfen treatment was approximately 87%. This method has the potential to increase parasitoid yield and reduce production costs in egg parasitoid rearing programs. The mass rearing of hymenopteran egg parasitoids requires an abundant supply of host eggs. The onset of reproductive diapause and subsequent decline in egg production poses a challenge for parasitoid rearing when using host colonies augmented by field-collected insects. We investigated the application of pyriproxyfen, a juvenile hormone analog, to induce oviposition in diapausing adult kudzu bugs, Megacopta cribraria (Fabricius) (Heteroptera: Plataspidae), and the use of eggs produced by pyriproxyfen-treated kudzu bugs to rear the egg parasitoid, Paratelenomus saccharalis (Dodd) (Hymenoptera: Scelionidae). The effects of pyriproxyfen and photoperiod treatments on host mortality, egg production, and rates of parasitoid eclosion from the eggs were used to calculate the parasitoid yield for the different treatment regimes. A combination of pyriproxyfen and a long-day photoperiod increased the parasitoid yield by 87% compared to acetone and a long-day photoperiod. The general applicability of JH-analog mediated egg production for parasitoid rearing is discussed. [ABSTRACT FROM AUTHOR]

Megacopta cribraria (Hemiptera: Plataspidae) has become a pest of soybean, Glycine max (L.), in the United States. While several natural enemies of M . cribraria have been reported, our study is the first to report nematodes beneath the pleural membranes in the abdominal cavities of adults. Morphological and molecular analyses suggest this nematode belongs to the family Mermithidae. This first report of a nematode infection in M . cribraria adds to the current inventory of enemies attacking this insect. Our observations provide a basis for future research to examine the impact of nematodes on M . cribraria mortality and to investigate their capacity to reduce populations. [ABSTRACT FROM AUTHOR]

The bean plataspid, Megacopta cribraria (F.) (Hemiptera: Plataspidae), is reported in Florida for the first time. It was found during Mar-Oct 2012 in kudzu patches (Pueraria montana Lour (Merr.) (Fabales: Fabaceae) in 16 Florida counties. Its host range includes kudzu, soybean (Glycine max Merrill; Fabales: Fabaceae), and other legume crops (Medal et al. unpublished data). [ABSTRACT FROM AUTHOR]

The kudzu bug, Megacopta cribraria, is a key pest of soybean in the United States. Electrophysiological and behavioral responses of adult M. cribraria to kudzu and soybean volatile compounds were examined to identify semiochemicals used for host location. Headspace volatiles collected from undamaged potted plants were analyzed by gas chromatography with electroantennographic detection (GC-EAD). Subsequently, six GC-EAD-active compounds were identified by gas chromatography-mass spectrometry (GC-MS). These six compounds, along with some previously reported insect attractants, were selected for electroantennogram (EAG) assays. The four chemicals that elicited the strongest EAG responses, 1-octen-3-ol, nonanal, benzaldehyde, and ocimene, were selected for evaluation in olfactometer bioassays. Both benzaldehyde and 1-octen-3-ol exhibited dose-dependent responses at higher concentration. Our results provide insight into host location compounds used by adult M. cribraria. These results may be evaluated in future field tests and ultimately useful to develop a semiochemical-based monitoring technique and integrated pest management program for M. cribraria.

We conducted a field study to determine seasonal egg parasitism rates of the kudzu bug Megacopta cribraria (F.) on the kudzu plant, Pueraria montana (Lour.) Merr. var. lobata (Willd.) Maesen et Almeida ex Sanjappa and Pradeep, in Tokyo, Japan, during the period from May 2014 to September 2014. The eggs of M. cribraria per 1 m2 of kudzu at four locations in Tokyo were collected weekly and parasitism rates were assessed. Eggs of M. cribraria were laid on the kudzu plant from May to September. Megacopta cribraria eggs were parasitized by two parasitoid species, Paratelenomus saccharalis (Dodd) and Ooencyrtus nezarae Ishii. Paratelenomus saccharalis first appeared in May, and its parasitism rates peaked in July and September. Ooencyrtus nezarae first appeared in June and its parasitism rates peaked in July. Except for one location which could not be statistically analyzed because of the small sample size, occurrence of parasitism by P. saccharalis and O. nezarae in M. cribraria egg masses was independent at one location and positively associated at two locations, suggesting that the use of host egg masses by P. saccharalis and O. nezarae is not mutually exclusive. Parasitism rates by P. saccharalis and O. nezarae were significantly lower for egg masses parasitized by both species than for those parasitized by a single species. The proportion of males among O. nezarae progeny was significantly higher for egg masses parasitized by O. nezarae together with P. saccharalis than for those parasitized by O. nezarae alone. These results suggest that parasitism of host egg masses by the two species is influenced by their interspecific interactions., (© The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The plataspid Megacopta cribraria (F.), an economic pest of soybeans, Glycine max (L.) Merrill, in Asia recently invaded North America and has become not only an important pest of soybean but also a nuisance pest. Although much is reported about M. cribraria in its native and invasive range, little information has been documented on the effect of temperatures on its development, longevity, and reproduction. We evaluated the influence of five constant temperatures (17-33°C) on the development, survival, fecundity, and population growth of M. cribraria in the laboratory. The developmental time for egg and nymph stages was shortened significantly with increasing temperature. The developmental time from egg to adult emergence was 114.81, 76.26, 44.54, and 38.54 d at 17, 21, 25, and 29°C, respectively. The nymphs of M. cribraria could not complete full development at a constant 33°C. The developmental threshold temperature estimated for egg to adult was 14.25°C, with a thermal constant of 849.56 degree-days. Females had the longest preoviposition period at 21°C (54.33 d), and the preoviposition period was shortened significantly as the temperature increased. Females had the longest oviposition period (35.33 d) and the highest fecundity (159.67 eggs per female) at 25°C and did not lay any eggs at 17°C. Female longevity was found to be shortest (44.0 d) at 29°C, and similar (75.67-81.50 d) at 17-25°C. The population trend index of M. cribraria was the highest (46.47) at 25°C, followed by 29°C (10.84) and 21°C (6.70). The results will be useful for predicting the phenology and population dynamics of M. cribraria and will provide some biological information on the invasive species in its nonnative range., (© 2014 Entomological Society of America.)