Influence of harmonic radar tag attachment on nymphal Halyomorpha halys mobility,survivorship, and detectability

The brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is a polyphagous invasive insect and currently one of the most threatening agricultural pests in the USA and globally. Nymphs are highly mobile, moving among host plants, and causing significant damage. Thus, understanding dispersal biology for all life stages is critical for the development of reliable monitoring and management programs. Here, we evaluated the influence of harmonic radar as a tool to study dispersal ecology of nymphal H. halys; we measured the impact of glues and tag attachment on survivorship and mobility in the laboratory and validated in the field that tagged and released nymphs could be tracked on baited and unbaited host and non‐host plants using harmonic radar. In the laboratory, four glues were evaluated for attaching harmonic radar tags securely to nymphs, and survivorship with attached tags was measured. There were no significant differences in survivorship or vertical and horizontal movement among nymphs with tags affixed with the glue treatments compared with the untagged control. Based on numerically greater survivorship of nymphs with tags affixed with Loctite glass glue, a field validation study of tagged nymphs released in host (apple tree) and non‐host (mowed grass) with or without H. halys pheromonal stimuli present revealed that nymphs could be successfully relocated using harmonic radar after 48 h. Among treatments, 83% of nymphs remained in baited and unbaited apple trees, 50% of nymphs remained in baited mowed grass plots, and in unbaited mowed grass plots, 17% of fifth instars, and 0% of fourth instars were retained. The absence of negative effects on mobility, survivorship, and field tracking validates that harmonic radar can be used to study dispersal ecology of nymphal H. halys.     

Development and comparison of trunk traps to monitor movement of Halyomorpha halys nymphs on host trees

Halyomorpha halys Stål (Hemiptera: Pentatomidae) has recently become a major orchard pest in the Mid‐Atlantic, USA. Large H. halys populations can develop on wild tree hosts adjacent to orchards, posing an ongoing threat to fruit. Adults and nymphs feed on tree fruit, causing economic injury. Understanding the seasonal patterns of nymphal host use among trees at the orchard‐woodland interface may aid the development of integrated pest management strategies for this pest. In laboratory and field experiments, modified versions of published trap designs – ‘Circle’, ‘Hanula’, ‘M&M’ (after Moeed & Meads) traps – were compared for their effectiveness for capturing H. halys nymphs walking up and down tree trunks. In the laboratory, second instars were released at the top and bottom of ailanthus (tree of heaven), Ailanthus altissima (Mill.) Swingle (Simaroubaceae), logs and captures were recorded after 24 h. Circle and M&M traps, respectively, were most effective for capturing nymphs walking up and down. In the field, traps were deployed on ailanthus trees next to apple orchards and captures were recorded weekly from 24 July to 11 September 2013. As in the laboratory, Circle and M&M traps captured the greatest number of upward‐ and downward‐walking nymphs. Hanula traps were least effective in both experiments. In the field, 88% of total captures were of nymphs walking up trees. This was at least partially explained by behavioral assays in the laboratory demonstrating that nymphs exhibited negative gravitaxis and positive phototaxis. Stage‐specific trends in captures of instars walking up during field sampling were observed. These results suggest that trunk traps can be used to address important ecological questions about seasonal patterns of host use by H. halys nymphs.     

Measuring host plant selection and retention of Halyomorpha halys by a trap crop

Trap cropping may exploit a pest's dispersal and host selection behavior in order to protect a desired crop. Here, we used a combination of visual sampling, immunomarking, and harmonic radar to assess host plant selection and retention time of the highly mobile and invasive Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), as it moves within and between a polyculture trap crop of sorghum and sunflower, and a bell pepper cash crop. Visual sampling demonstrated no significant differences in H. halys densities across crops, whereas dislodging stink bugs to collect for protein analysis revealed ca. 4× more bugs in the trap crop plants than in the peppers. In total 145 H. halys were collected and of these 6% were doubly marked with proteins, demonstrating that minimal movement occurred between the two planting systems. Tracking tagged H. halys with harmonic radar revealed that the trap crop retained adult H. halys within the plots 1.5× longer and reduced their movement by nearly half compared with bugs released in the pepper cash crop. The data suggest the trap crop of sunflower plus sorghum has the potential to attract and arrest the invasive H. halys, demonstrating that trap cropping may operate as an effective management tool.     

Effect of deltamethrin-incorporated nets on mobility and survivorship of Halyomorpha halys (Hemiptera: Pentatomidae) adults and nymphs in the laboratory

The brown marmorated stink bug, Halyomorpha halys Stål (Hemiptera: Pentatomidae), is an invasive pest that attacks specialty and row crops in North America and Europe. There has been a concerted effort to reduce frequent broad-spectrum insecticide applications made on vulnerable crops. One tool that has emerged recently is the use of long-lasting insecticide-treated nets (LLINs) as a killing agent. Here, we conducted bioassays to evaluate the effect of direct contact on deltamethrin-impregnated LLINs on the behaviour and survivorship of H. halys nymphs and adults in the laboratory. Following exposure at three different durations (1.25, 4.25 or 7.25 min), vertical and horizontal mobility of adults and nymphs and the flight capacity of adults were recorded and compared with individuals that were not exposed (control). Exposure to LLINs reduced the horizontal distance and velocity and increased the angular velocity of adults only but reduced vertical mobility of adults and nymphs. Adult flights were not significantly affected by LLIN exposure. Mortality of adults and nymphs at 7-day post-exposure ranged from 73% to 77% regardless of exposure time. We discuss our findings within the context of the potential for and limitations of deploying LLINs in vulnerable crops to manage H. halys populations.     

Behavioural response of the invasive Halyomorpha halys (Hemiptera: Pentatomidae) to host plant stimuli augmented with semiochemicals in the field

相似文献   

Phenology of brown marmorated stink bug described using female reproductive development

Temperature‐based degree‐day models describe insect seasonality and to predict key phenological events. We expand on the use of a temperature‐based process defining timing of reproduction through the incorporation of female reproductive physiology for the invasive pentatomid species Halyomorpha halys, the brown marmorated stink bug. A five‐stage ranking system based on ovary development was able to distinguish between the reproductive statuses of field‐collected females. Application of this ranking method described aspects of H. halys’ seasonality, overwintering biology, and phenology across geographic locations. Female H. halys were collected in the US from NJ, WV, NC, OR, and two sites in PA in 2006–2008 (Allentown, PA only) and 2012–2014. Results identify that H. halys enters reproductive diapause in temperate locations in the fall and that a delay occurs in developmental maturity after diapause termination in the spring. Modification of the Snyder method to identify biofix determined 12.7‐hr photoperiod as the best fit to define initiation of reproduction in the spring. Applying the biofix, we demonstrated significant differences between locations for the rate at which the overwintering generation transition into reproductive status and the factors contributing to this difference require further study. For example, after including abiotic variables influencing development such as temperature and photoperiod (critical diapause cue), reproduction occurred earlier in OR and for an extended period in NJ. This data describe a method to investigate insect seasonality by incorporating physiological development across multiple regions that can clarify phenology for insects with overlapping generations.     

Colonization preference of Euschistus servus and Nezara viridula in transgenic cotton varieties,peanut, and soybean

Producers of Bt cotton, Gossypium hirsutum L. (Malvaceae), in the southeastern USA face significant losses from highly polyphagous stink bug species. These problems may be exacerbated by crop rotation practices that often result in cotton, peanut, Arachis hypogaea L., and soybean, Glycine max (L.) Merrill (both Fabaceae), growing in close proximity to one another. Because all of these crops are hosts for the major pest stink bug species in the region, we experimentally examined colonization preference of these species among the crops to clarify this aspect of their population dynamics. We planted peanut, soybean, Bt cotton, and glyphosate‐tolerant (RR) non‐Bt cotton at three sites over 3 years in replicated plots ranging from 192 to 1 323 m² and calculated odds ratios for colonization of each crop for Nezara viridula (L.) and Euschistus servus (Say) (both Hemiptera: Pentatomidae). In four of five experiments, both E. servus and N. viridula preferred soybean significantly more often than Bt cotton, non‐Bt cotton, and peanut. Neither N. viridula nor E. servus showed any preference between non‐Bt and Bt cotton in any experiment. Both species had higher numbers in Bt and non‐Bt cotton relative to peanut; this was not significant for any single experiment, but analyses across all experiments indicated that N. viridula preferred Bt and non‐Bt cotton significantly more often than peanut. Our results suggest that soybean in the landscape may function as a sink for stink bug populations relative to nearby peanut and cotton when the soybean is in the reproductive stage of development. Stink bug preference for soybean may reduce pest pressure in near‐by crops, but population increases in soybean could lead to this crop functioning as a source for later‐season pest pressure in cotton.     

Presence of the invasive brown marmorated stink bug Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) on home exteriors during the autumn dispersal period: Results generated by citizen scientists

相似文献   

Relative longevity of adult Nezara viridula in field cages of cotton,peanut, and soybean

Producers in the southeastern USA face significant crop losses from the stink bugs Nezara viridula (L.), Euschistus servus (Say), and Chinavia hilaris (Say) (all Hemiptera: Pentatomidae). Cotton, peanut, and soybean are major agronomic crops and host plants of stink bugs in the region. We conducted a field plot study to measure the relative longevity of adult, unmated N. viridula males and females caged on peanut, cotton, and soybean to test three hypotheses: (1) differences in mortality are associated with differences in host plant food suitability, (2) mortality rates increase with age, and (3) males have higher mortality than females. Using survival analysis, we found that the sex of the individual did not affect survival rates on any of the three host plants. Survival was significantly higher in cotton and soybean than in peanut. Mortality rates increased with age in peanut, but not in soybean or cotton. The frequency of canopy temperatures above 35 °C was higher in peanut than in soybean. Peanut appears to be a less than ideal habitat in terms of canopy temperature and/or food quality for N. viridula adults. Both, cotton and soybean were equally suitable food resources for N. viridula adults prior to maturation of the plants.     

Lethal and sublethal effects of long‐lasting insecticide‐treated nets on the invasive bug Halyomorpha halys

Halyomorpha halys is a polyphagous insect species with an original eastern Asiatic distribution, which was recently and accidentally introduced in the USA and Europe, where it became a serious agricultural pest. Chemicals have been widely used for its control leading often to failure of IPM programmes. Several approaches aimed at pest monitoring and control are currently under investigation, for example trapping, screening, border management and biological control. In the present work, we investigated the lethal and sublethal effects of the use of a long‐lasting insecticide‐treated net (LLIN with α‐cypermethrin), focusing on the perspective to control H. halys in an integrated approach. All experiments were carried out in the laboratory either in small arenas, at five exposure times (5, 15, 30, 45 and 60 min) or in large cages at 8 hr exposure. In small arenas, the LLIN induced sublethal effects and/or effectively killed the adults. A higher adult mortality was observed after longer exposure times (LT₉₀ was 51.64 min for females and 40.83 min for males). However, several specimens recovered from sublethal effects, with higher recovery rates after shorter exposure times. In the cage experiments, a significantly higher mortality (65% males and 75% of females) was recorded compared with controls. LLINs are physical barriers that can improve crop protection due to their insecticidal activity, and can be reasonably applied in various attract‐and‐kill systems both in glasshouses and in the field.     

Parasitism of frozen Halyomorpha halys eggs by Trissolcus japonicus: applications for rearing and experimentation

The brown marmorated stink bug, Halyomorpha halys (Stål), has become a well-known pest to growers and homeowners since its 1996 introduction to the United States. A classical biocontrol programme is under development using the egg parasitoid Trissolcus japonicus. Widespread implementation of biocontrol requires efficient mass rearing, which is constrained by the availability of fresh H. halys eggs. In this study, parasitism rate, developmental time, sex ratio and size were compared between wasps reared on fresh versus frozen, newly laid (<1 d old) versus variably aged (0–3 d old), and frozen egg masses stored ≤4 y. Frozen eggs yielded 56–65% fewer wasps, with parasitism rate decreasing 1–3% per month stored. Parasitism rate, sex ratio and developmental time were comparable between newly laid and variably aged eggs. Freezing eggs for any duration did not affect sex ratio or weight of emerged wasps, but delayed emergence 5–6 d. To simulate deployment of sentinel eggs in the field, we incubated frozen eggs at 20°C and 30°C for 1–9 d before exposing them to T. japonicus, then evaluated parasitism trends. Trissolcus japonicus parasitism rate decreased 5–8% per day incubated, unhatched wasps increased 9% per day incubated and sex ratio was not impacted. Variably aged, frozen and longer stored eggs can be used for T. japonicus rearing and experimentation without affecting emerged wasp sex ratio or size within one generation, but have lower parasitism and slower development. Frozen sentinel eggs are effective <3–5 d, especially in hot conditions.     

Repellent activity of essential oils on adults of Halyomorpha halys (Heteroptera: Pentatomidae) in different physiological-behavioural phases

The brown marmorated stink bug Halyomorpha halys is an invasive agricultural pest in North America and Europe, and also a dwelling nuisance in autumn, due to the overwintering adults aggregating inside buildings. The repellent potential of ginger, clove, vetiver and turmeric essential oils (EOs) was tested on H. halys adults of three different physiological-behavioural phases: exiting overwintering (EXOV), active during summer (SUMM) and entering overwintering (ENOV). In a two-choice apparatus, fresh food was used as an attractant in both sides, together with three males when testing ENOV individuals. A filter paper with different concentrations of the EOs was the treatment side, and a filter paper with ethanol acted as control. The position of the individually tested bugs was recorded after 1, 6 and 24 hr. All tested EOs were repellent at concentrations higher than 3%, independent of sex or length of exposure. Turmeric and clove were the most repellent EOs, whereas ginger and vetiver showed on average a medium-to-low repellency. Significant differences emerged among the physiological-behavioural phases, with SUMM individuals showing a greater repellency to many of the tested concentrations, and EXOV individuals being overall the least susceptible to these substances. The response to vetiver oil was ambiguous, as at 25%, it elicited both a strong repellency in SUMM and a strong attraction in EXOV. Turmeric and clove EOs are promising candidates in integrated pest management strategies to reduce attacks by H. halys to susceptible crops especially during summer, as well as to prevent the entrance of overwintering bugs in buildings in autumn.     

Field collection of egg parasitoids of Pentatomidae and Scutelleridae in Northwest Italy and their efficacy in parasitizing Halyomorpha halys under laboratory conditions

The invasion of Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) has caused severe economic damage in crops in North America and Europe, motivating research to identify its natural enemies, both in native and invaded areas. In its Asian native range, the main natural enemies are egg parasitoids, among which the most effective are Trissolcus japonicus (Ashmead) and Trissolcus mitsukurii (Ashmead) (Hymenoptera: Scelionidae) in China and Japan, respectively. In Europe, biology, host range, and impact of most native scelionid species are not well‐known. The present study aimed to investigate (1) presence and abundance of scelionid species that parasitize native Pentatomidae and Scutelleridae eggs in Northwest Italy, and (2) their ability to develop on H. halys eggs. During 4‐year field surveys, egg masses were collected and reared until bug nymph or adult parasitoid emergence. Then, the obtained scelionid females were tested for their ability to parasitize H. halys eggs in laboratory no‐choice experiments. Egg masses of all collected bug species were parasitized, and Telenomus spp. (Hymenoptera: Scelionidae), Trissolcus belenus (Walker), and Anastatus bifasciatus (Geoffroy) (Hymenoptera: Eupelmidae) were the most common parasitoids. In the laboratory, Trissolcus kozlovi Rjachovskij was the only species to significantly produce offspring from fresh H. halys eggs, whereas all tested Trissolcus species significantly induced host egg abortion (non‐reproductive effects). This study provides knowledge of the parasitoid species associated with native bugs, and represents a starting point to investigate the intricate interactions between native and exotic parasitoids recently found in northern Italy. These egg parasitoids could potentially be effective biocontrol agents of H. halys.     

Seasonal body weight, lipid content, and impact of starvation and water stress on adult survivorship and longevity ofNezara viridula andEuschistus heros

Fresh and dry body weights (FW, DW) were greater for adult southern green stink bug,Nezara viridula (L.) than for the brown stink bug,Euschistus heros F. throughout the year in southern Brazil. FemalesN. viridula significantly increased FW and DW in late summer-early autumn, and during mid-spring; femaleE. heros did not show the same rates of increase in FW and DW. FemaleN. viridula were heavier than males, particularly during summer; however, female and maleE. heros were generally similar in weight.E. heros contained significantly greater amounts of lipid thanN. viridula, during mid-autumn to early-spring (April–September). Survivorship (%) and total longevity ofE. heros adults provided water only was greater (34.6–24.6 days, for females and males) than that forN. viridula (14.8–13.0 days); without water and food, longevity was drastically reduced (<7 days) for both species.     

Role of symbiotic gut bacteria in the development of Acrosternum hilare and Murgantia histrionica

The green stink bug, Acrosternum hilare (Say), and the harlequin bug, Murgantia histrionica (Hahn) (both Heteroptera: Pentatomidae), are pests of many economically important crops. Although both species have been studied extensively, until recently their relationships with symbiotic gut bacteria have remained unknown. The endosymbionts may be important, as other pentatomomorphan species harbor vertically transmitted gut bacteria that play an important role in the biology of their host insects. We report the role of gut symbiotic bacteria on the development and fitness of A. hilare and M. histrionica by comparing control insects with individuals that hatched from surface sterilized egg masses. We studied the life history of A. hilare and M. histrionica under laboratory conditions at 23 ± 2 °C and L16:D8, measuring nymphal mortality and development time, and estimating other demographic parameters. We also evaluated egg masses, nymphs, and adults of both species with diagnostic PCR primers for the presence of specific gut symbiotic bacteria for both treatments. Our results show that egg mass surface sterilization eliminates or reduces the prevalence of this bacterium-insect symbiosis in both species. Acrosternum hilare 's development time, survivorship, and other demographic parameters were negatively affected by surface sterilization of egg masses. Conversely, M. histrionica 's survivorship was marginally increased by clearing its symbiont infection during the first generation; however, mean generation time was significantly longer. Our data indicate that the degree of mutualism in this association for pentatomid species is variable, given that A. hilare requires its symbiont for adequate development and survival, whereas M. histrionica 's symbiont may not be required for development and survival under the experimental conditions used.     

The bimodal adult activity of Monochamus alternatus (Coleoptera: Cerambycidae) caught in pheromone traps in Jeju can be explained by the competitive attractiveness of dying pine trees

The Japanese pine sawyer, Monochamus alternatus Hope (Coleoptera: Cerambycidae), is known to be the primary vector of pinewood nematode Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle that causes pine wilt disease. Adult activity of M. alternatus caught in a pheromone trap on Jeju Island of Korea showed a bimodal form with the first peak in mid to late June and the second peak in mid to late September. The two peaks were separated between mid and late August, showing a valley. Accumulated degree‐days predicted that the emergence of the second generation adults could be possible just before the second peak. But actually no adults of the second generation occurred in the field development experiments of M. alternatus in 2016 and 2017. Pine trees without oleoresin flow (namely dying trees by the infection of pinewood nematode) were abundant during early July to early August. The bimodal adult activity pattern of M. alternatus could be partially explained by the competitive attractiveness of dying trees against pheromone traps, when we accepted the assumption that dying pine trees attract strongly M. alternatus.     

Host preference and suitability of grasses for Oebalus pugnax

The rice stink bug, Oebalus pugnax (Fabricius) (Hemiptera: Pentatomidae: Carpocorini), though graminaceous, discriminates among its numerous host grass species. This could represent a feeding preference, it could be related to host suitability for growth and development. To clarify the role of host grass discrimination, two laboratory studies were conducted: (1) free‐choice tests to evaluate preferences of O. pugnax among 11 wild host grass species found in three rice‐producing counties of the central Mississippi Delta (MS, USA), and (2) no‐choice tests to evaluate the impact of rice (Oryza sativa L.), junglerice [Echinochloa colona (L.) Link], and dallisgrass (Paspalum dilatatum Poir.) (all Poaceae), on the development of O. pugnax from second instar to adult. In the free‐choice test, four experiments were conducted, each with four sets of host grass species and observed 1, 2, 4, 8, and 16 h after release in cages. Approximately 4 h was necessary for O. pugnax to settle on preferred host grasses. Oebalus pugnax showed a feeding preference for junglerice over all 10 other grass species. Bahiagrass, Paspalum notatum Flueggé, was the least preferred. The no‐choice tests showed significant effect of host grass species on O. pugnax mean development time of nymphal survival to adults. Survival of nymphs was lower and mean development time was longer on dallisgrass compared to rice and junglerice. Knowledge of O. pugnax rate of growth and development on host grasses could be useful in the future development of rice integrated pest management strategies.