Green Stink Bug Research Articles

Damage to Soybean by Acrosternum hilare (Say) (Heteroptera: Pentatomidae)

A series of field-cage experiments were conducted in 2002 and 2003 in southeast Arkansas to measure the impact of feeding by green stink bug, Acrosternum hilare (Say), on soybean yield and seed damage. Stink bugs were collected from local soybean fields and released in 1.8 × 1.8 × 1.8 m walk-in screen cages at densities of 0, 3, 9, and 18 bugs per row-m on maturity group (MG) IV and MG V soybean at different stages of crop phenological development. Damaged seed at harvest was significantly related to caged density of A. hilare in most of the cage experiments. Yield loss was associated with density of caged bugs in 7 of 11 different experiments and ranged from 13.4–60.5 kg/ha (0.2–0.9 bu/a) lost per bug per row-m. MG IV and MG V soybean were similarly impacted by density of A. hilare when exposed at the same stage of crop development. Feeding by small and large nymphs at early (R2–R3) and mid (R5–R6) reproductive stages resulted in significant yield loss. Feeding damage was apparent on late reproductive stage soybean (R7–R8), but no measurable impact on yield was observed. This suggested that thresholds could be raised or control efforts could be terminated for stink bugs infesting R7–R8 stage soybean. Damage due to feeding by stink bugs is related to various factors, but crop phenology, density of bugs, and length of infestation time are consistent and predictable influences that are interrelated, and all should be considered in determining the need to control field populations.

Viabilidade de ovos de Nezara viridula (L.) armazenados a baixas temperaturas para o parasitismo por Trissolcus basalis (Woll.)

Four storage techniques of eggs of green stink bug, Nezara viridula , are compared. Research work aims at utilizing egglaying for posterior parasitism by Trissolcus basalis . Experiment was performed at the Entomology Laboratory of the Agronomy Department at the State University of Maringa, Maringa PR Brazil. Eight batches of 60 eggs of Nezara viridula , stored according to four techniques, were employed: Technique I: conservation in fridge at 2oC; Technique II: conservation in refrigeration section of fridge at -10oC; Technique III: conservation in freezer at -18C; Technique IV: conservation in liquid nitrogen at -196oC. After storage, eggs underwent parasitism by three 2-day-old females of T. basalis for 24 hours. Egg batches were kept in climatized chamber till total emergence and death of wasps. Emergence rate and sexual ratio were recorded. Results showed that high sexual ratio and emergence tax are proportionate to low storage temperature. Conservation at -2oC and -10oC do not allow extensive storage periods

The effect of vibratory disturbance on sexual behaviour of the southern green stink bug Nezara viridula (Heteroptera, Pentatomidae)

Abstract The effect of vibratory disturbance on sexual behaviour and substrate-borne sound communication of the southern green stink bug, Nezara viridula L. was studied. Disturbance signals do not change the time N. viridula males need to locate the source of vibratory signals, but decrease the number of males responding with the calling and courtship song to calling females. Female N. viridula proceed calling during stimulation with disturbance signals but some of them change the song rhythm by skipping one or more signal intervals or emitting the repelling signals. The number of females which change the dominant frequency of the calling song decreases proportionally with increasing differences between the dominant frequency of the disturbance signals and the emitted female calling song. Variation of the song dominant frequency probably serves females to avoid interference by increasing the signal to noise ratio. Signal duration and repetition rate do not change significantly when the female is stimulated with the disturbance signals. This indicates that frequency shift by calling females is the main strategy for reducing interference by competitive signalers in N. viridula vibrational communication.

Populations of Stink Bugs (Heteroptera: Pentatomidae) and their Natural Enemies in Peanuts

The objective of this on-farm study was to determine if peanuts harbor populations of stink bugs (Heteroptera: Pentatomidae) and their natural enemies in Georgia. Eight species of phytophagous stink bugs were found in peanuts over the 5-yr study. The predominant stink bug species were Nezara viridula (L.), Euschistus servus (Say), Euschistus quadrator (Rolston), and Oebalus pugnax pugnax (F.). The remaining 4 species, Acrosternum hilare (Say), Euschistus tristigmus (Say), Euschistus ictericus (L.), and Thyanta custator accerra McAtee, were found in relatively low numbers. All developmental stages of N. viridula, E. servus, E. quadrator, A. hilare, and O. p. pugnax were collected at various times in the study indicating that these 5 species of stink bugs were developing on this crop. Seasonal abundance of N. viridula and E. servus nymphs and adults provided further support that these 2 species of stink bugs developed on peanuts. At least 1 generation of N. viridula and E. servus occurred in peanuts each year, and generally some of the adults that developed on peanuts oviposited on peanuts producing another generation of nymphs in this crop. Because only adults of T. c. accerra, E. tristigmus, and E. ictericus were found in peanuts, these 3 stink bug species probably were not developing on this crop. Adult stink bugs were parasitized by the tachinid parasitoids Trichopoda pennipes (F.) and Cylindromyia spp. Stink bug eggs were parasitized by the scelionids, Trissolcus basalis (Wollaston), Trissolcus thyantae Ashmead, Trissolcus brochymenae (Ashmead), Telenomus podisi Ashmead, and Gryon obesum Masner, and an unknown encyrtid species. Geocoris punctipes (Say), Geocoris uliginosus (Say), Orius insidiosus (Say), Podisus maculiventris (Say), and Oxyopes salticus Hentz preyed on stink bugs in peanuts. Peanuts harbor populations of stink bugs and their natural enemies, and thus the role peanuts play in landscape ecology of stink bugs needs to be ascertained to better understand how to manage stink bug populations in landscapes in which peanuts are associated with other crops.

Insect Pests and Yield Potential of Vegetable Soybean (Edamame) Produced in Georgia

A series of replicated field experiments was conducted with vegetable soybean (edamame), Glycine max (L.) Merrill, to assess the impacts of cultivars, planting dates, and insecticidal controls on insect pest abundance, crop damage and yield potential. The velvetbean caterpillar, Anticarsia gemmatalis Hübner, was the most common lepidopteran defoliator in this study, causing heavy defoliation in some years when left untreated. Other lepidopterans observed included the soybean looper, Pseudoplusia includens (Walker), and the green cloverworm, Hypena scabra (F.). Stink bugs, primarily the southern green stink bug, Nezara viridula (L.), also caused seed damage in some cultivars when left untreated. Stink bug damage exceeded expectations on edamame seeds when exposed to moderate stink bug densities (≤3 bugs per 25 sweeps). Other arthropods that were commonly observed included threecornered alfalfa hoppers, Spissistilus festinus (Say), grasshoppers, Melanoplus spp., and the potato leafhopper, Empoasca fabae (Harris). Arthropod infestations on edamame were similar to reported pest problems on conventional soybeans being produced for oil and meal. Midseason applications of the insecticides diflubenzuron plus l-cyhalothrin reduced insect pest populations, percentage of arthropod-induced defoliation and percentage of seeds damaged by stink bugs, but had little effect on edamame yields. Most defoliation and seed damage occurred during R5 development when seeds were approaching full size, thus only minimal yield reductions were noted. However, seed quality of the untreated vegetable soybeans would be unacceptable for the consumer. Total fresh green yields ranged from 2343–11,895 kg ha−1, depending on year, cultivar and planting date, whereas fresh green seed yields ranged from 1208–6,119 kg ha−1. Early-maturing edamame cultivars planted in April had fewer insect pests and less damage than the cultivars planted later. Avoidance of insect pests is an important production consideration for insect management, especially critical in an organic production system. The fresh green seed yields produced during this study demonstrate that this emerging alternative crop has the potential for economic success in the southern region, assuming that the arthropod pests are effectively managed to maintain acceptable edamame quality and yield.

Morphology and physiology of vibratory interneurons in the thoracic ganglia of the southern green stinkbugNezara viridula(L.)

The central processing mechanisms of vibratory signals in small plant-dwelling insects that rely primarily on substrate-borne vibratory communication are still largely unknown. To elucidate the neural mechanisms involved in vibratory signaling, the vibration-sensitive interneurons in thoracic ganglia of the southern green stinkbug, Nezara viridula, were investigated electrophysiologically by single-cell recordings and staining. Ten types of interneurons were described and divided into four categories, based on their gross morphology. The cell body of the L-shaped CG-AC neurons is located in the metathoracic neuromere of the central ganglion, and the axon ascends contralaterally. This group comprises five types of neurons differing in their fine structure and functional properties. CG-AB neurons are dorsal unpaired median (DUM) neurons with cell bodies in the mesothoracic neuromere of the central ganglion and two axons that ascend bilaterally into the prothoracic ganglion. Group CG-L includes three types of local neurons limited to the central ganglion. With ipsilateral dendritic arborizations and contralateral axonal branching, their gross morphology is similar to that of cricket omega cells. Interneuron PTG-DC, with the cell body in the prothoracic ganglion (PTG) and a contralaterally descending axon, conveys information received by the sensory organs of the front contralateral leg to the neuropil regions of the ipsilateral middle and hind legs. Based on their frequency tuning and acceleration sensitivity, the vibratory interneurons fall into two groups: the low-frequency units are tuned to 50 Hz and the middle frequency units to 200 Hz, with their acceleration thresholds at 10(-1) m/s(2) and 5 x 10(-3) m/s(2), respectively. Their function is discussed with relevance to the vibratory communication of N. viridula.

Identification of Stink Bugs Using an Electronic Nose

Stink bugs are recognized as pests of several economically important crops, including cotton, soybean and a variety of tree fruits. The Cyranose 320 was used for the classified investigation of stink bug. Stink bugs including males and females of the southern green stink bugs, Nezara viridula, were collected from crop fields around College Station, TX. Results show that the released chemicals and chemical intensity are both critical factors, which determine the rate that the Cyranose 320 correctly identified the stink bugs. The Cyranose 320 shows significant potential in identifying stink bugs, and can classify stink bug samples by species and gender.

Effects of Vegetated Field Borders on Arthropods in Cotton Fields in Eastern North Carolina

The influence, if any, of 5m wide, feral, herbaceous field borders on pest and beneficial arthropods in commercial cotton, Gossypium hirsutum (L.) (Malvales: Malvaceae), fields was measured through a variety of sampling techniques over three years. In each year, 5 fields with managed, feral vegetation borders and five fields without such borders were examined. Sampling was stratified from the field border or edge in each field in an attempt to elucidate any edge effects that might have occurred. Early season thrips populations appeared to be unaffected by the presence of a border. Pitfall sampling disclosed no differences in ground-dwelling predaceous arthropods but did detect increased populations of crickets around fields with borders. Cotton aphid (Aphis gossypii Glover) (Hemiptera: Aphididae) populations were too low during the study to adequately assess border effects. Heliothines, Heliothis virescens (F.) and Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), egg numbers and damage rates were largely unaffected by the presence or absence of a border, although in one instance egg numbers were significantly lower in fields with borders. Overall, foliage-dwelling predaceous arthropods were somewhat more abundant in fields with borders than in fields without borders. Tarnished plant bugs, Lygus lineolaris (Palisot de Beauvois) (Heteroptera: Miridae) were significantly more abundant in fields with borders, but stink bugs, Acrosternum hilare (Say), and Euschistus servus (Say) (Hemiptera: Pentatomidae) numbers appeared to be largely unaffected by border treatment. Few taxa clearly exhibited distributional edge effects relative to the presence or absence of border vegetation. Field borders like those examined in this study likely will have little impact on insect pest management in cotton under current insect management regimens.

Seasonal Abundance of Stink Bugs (Heteroptera: Pentatomidae) and Other Polyphagous Species in a Multi-Crop Environment in South Arkansas

A 3-yr study was conducted to determine seasonal abundance of major pentatomid, noctuid, and mirid pests in a multicrop environment in south Arkansas. Replicated field plots (~0.1 ha) containing cotton, Gossypium hirsutum (L.), genetically engineered to express the Cry 1Ac toxin of Bacillus thuringiensis (Bt), nonBt cotton, Bt corn, Zea mays (L.), genetically engineered to express the Cry 1Ab toxin of B. thuringiensis, nonBt corn, maturity group (MG) III, IV, V, and VI soybean, Glycine max (L.) Merrill, and grain sorghum, Sorghum bicolor (L.) Moench, were planted each year. Crop preferences of 3 stink bug species [southern green stink bug, Nezara viridula (L.), green stink bug, Acrosternum hilare (Say), and brown stink bug, Euschistus servus (Say)] were recorded and observations also were made on the relative abundance of corn earworm, Helicoverpa zea (Boddie), tobacco budworm, Heliothis virescens (F.), and tarnished plant bug, Lygus lineolaris (Palisot de Beavois). Significantly higher densities of stink bugs were present in MG IV soybean than in all other crops in July and August during all 3 yrs of study. Densities of heliothines were significantly greater in grain sorghum and corn than in other crops during July. Tarnished plant bugs were most commonly observed in cotton. Preferences of these polyphagous pests for different crops at specific stages of phenological development appear to be predictable aspects of insect behavior that may be exploited in trap crops or other landscape management systems.

EVALUATION OF SELECTED INSECTICIDES FOR CONTROL OF STINK BUGS AND THREE-CORNERED ALFALFA HOPPERS, 2007

Selected insecticides were evaluated for control of red banded, southern green, and brown stink bugs (adults and nymphs) and three-cornered alfalfa hoppers (adults and nymphs: TCAH) in a field trial at the Macon Ridge Research Station (Franklin Parish). Soybean seed (DP 4646) were planted into a Gigger silt loam soil on 10 May. Plot size was eight rows (40-inches on centers) x 50 ft. Treatments were placed in a RCB design with nine replications. Insecticides were applied on 8 Aug with a John Deere high clearance sprayer and CO2-charged system calibrated to deliver 6 gpa through Teejet TX-6 hollow cone nozzles (2/row) at 48 psi. Treatment efficacy against stink bugs and TCAH was determined at 2, 5, and 7 DAT using a standard (15 inches diameter) sweep net by taking 25 sweeps in each plot. Stink bug data was pooled into total stink bug adults (SBA), total stink bug nymphs (SBN), and total stink bugs (SBTOT). Data were subjected to ANOVA and means separated according to DMRT. No rainfall occurred during these tests.

The adequacy of artificial oviposition substrates for laboratory rearing of Piezodorus guildinii (Westwood) (Heteroptera, Pentatomidae)

Studies in the laboratory tested the suitability of synthetic wool string, cotton string, cheesecloth, and commercial cotton ball as artificial oviposition substrates for the small green stink bug, Piezodorus guildinii (Westwood) (Heteroptera, Pentatomidae). In confined cages, 54% of total egg masses was laid on synthetic wool string, 31% on cotton string, and only 15% on cheesecloth. In an additional test, the best substrate selected, synthetic wool string, received 92% of egg masses compared to 8% on the commonly used substrate, cotton ball. Synthetic wool string received the most egg masses of any size, in particular those in the range 11-20 eggs/mass. Because the eggs of P. guildinii are laid in two parallel double rows, the egg masses fit the wool string perfectly.

Texas Gulf Coast Soybean Yield Affected by Soybean Variety and Planting Date

Soybeans (Glycine max) are planted along the upper Texas Gulf Coast from mid-March through May to try to take advantage of early season spring and summer rains and also to complete harvest before hurricane season and fall rains become a problem. These plantings are with maturity groups (MG) IV and V and are mainly grown under nonirrigated conditions. Under normal rainfall conditions (rainfall in April, May, and early June), this study shows that a late March or early April planting date provided the highest yield although a May plant date can result in yields of greater than 50 bu/acre if rainfall is received at the proper times. However, when planting was delayed, there was a greater risk of detrimental late-season effects from drought and southern green stink bug (Nezara viridula) or the brown stink bud (Euschistus heros). In 2004 and 2005, at both locations, soybeans planted at the early plant date took longer to reach physiological maturity than the later plant dates. Generally, the earlier the plant date, the greater number of days from planting till harvest.

Long-term patterns and feeding sites of southern green stink bug (Hemiptera: Pentatomidae) in Hawaii macadamia orchards, and sampling for management decisions

Southern green stink bug (Nezara viridula, Hemiptera: Pentatomidae) is a pest of macadamia nuts, causing pitting to kernels by feeding. In spite of its pest status, many aspects of the ecology of this insect in macadamia orchards are poorly understood. This study analyzes long-term N. viridula damage to macadamia nuts and investigates the extent to which damage to nuts occurs in the tree canopy, prior to nut-drop. We show that there are distinct seasonal peaks in damage detected after harvest and that, over six years of data collection, mean damage levels were fairly low, albeit with spikes in damage levels recorded. Sampling nuts at peak harvest periods from different strata in the trees and from the ground showed that incidence of damaged nuts within the canopy was typically half as high as on the fallen nuts. Damage to fallen nuts may have occurred prior to nut-drop, and continued to accumulate after nut-drop. These results show that management of N. viridula within macadamia canopies, as opposed to only on fallen nuts, is important. A sampling procedure and predictive model for estimating late-season damage based on early-season damage samples is provided. The model uses January and March damage measurements (based on samples with set level of accuracy), mean temperature and month of the year for which damage is predicted. Early-season damage of 6-10% predicts late-season damage levels that should justify N. viridula suppression based on the nominal threshold (13% damage) used by kernel processors to reject nuts based on damage.

Field Screening of Experimental Corn Hybrids and Inbred Lines for Multiple Ear-Feeding Insect Resistance

Identifying and using native insect resistance genes is the core of integrated pest management. In this study, 10 experimental corn, Zea mays L., hybrids and 10 inbred lines were screened for resistance to major ear-feeding insects in the southeastern Coastal Plain region of the United States during 2004 and 2005. Ear-feeding insect damage was assessed at harvest by visual damage rating for the corn earworm, Helicoverpa zea (Boddie), and by the percentage of kernels damaged by the maize weevil, Sitophilus zeamais Motschulsky, and stink bugs [combination of Euschistus servus (Say) and southern green stink bug, Nezara viridula (L.)]. Among the eight inbred lines and two control populations examined, C3S1B73-5b was resistant to corn earworm, maize weevil, and stink bugs. In contrast, C3S1B73-4 was resistant to corn earworm and stink bugs, but not to maize weevil. In a similar manner, the corn hybrid S1W*CML343 was resistant to all three ear-feeding insects, whereas hybrid C3S1B73-3*Tx205 was resistant to corn earworm and maize weevil in both growing seasons, but susceptible to stink bugs in 2005. The silk-feeding bioassay showed that corn earworm developed better on corn silk than did fall armyworm. Among all phenotypic traits examined (i.e., corn ear size, husk extension, and husk tightness), only corn ear size was negatively correlated to corn earworm damage in the inbred lines examined, whereas only husk extension (i.e., coverage) was negatively correlated to both corn earworm and maize weevil damage on the experimental hybrids examined. Such information could be used to establish a baseline for developing agronomically elite corn germplasm that confers multiple ear-feeding insect resistance.

Influence of <I>Nezara viridula</I> Feeding on Cotton Yield, Fiber Quality, and Seed Germination

The influence of southern green stink bug, Nezara viridula (L.), adults (males and females) and fourth to fifth instars on cotton, Gossypium hirsutum L., boll abscission, seedcotton yield, fiber quality, and seed viability was evaluated in field studies conducted during 2004 and 2005. Cotton bolls representing several age classes ranging from 0-600 heat units were individually infested with a specific gender or life stage of southern green stink bug. Adults and nymphs induced abscission of bolls that accumulated 0-280 heat units after anthesis. Seedcotton yield was significantly lower in bolls infested with adults (males and females) and late instars through approximately 500 heat units after anthesis. Southern green stink bug feeding on bolls significantly affected the physical fiber properties of micronaire (measure of fiber fineness or maturity), strength, uniformity, and fiber length. Discolored cotton lint in the stink bug-infested bolls was more common than in noninfested bolls. Seed germination and development of normal seedlings for seed harvested from stink bug-infested bolls that accumulated < or =500 heat units beyond anthesis were significantly lower compared with noninfested bolls. No significant differences in boll abscission, yield, fiber quality, and seed germination were detected between southern green stink bug males and females or between adults and fourth to fifth instars.

Assessing Stink Bug Resistance in Soybean Breeding Lines Containing Genes from Germplasm IAC-100

Sixty-five soybean, Glycine max (L.) Merr., breeding lines containing the stink bug resistant ‘IAC-100′ in their pedigrees were evaluated for their resistance to stink bug, primarily southern green stink bug, Nezara viridula L., feeding in replicated field trials from 2001 to 2005. Plots were sampled throughout the season for stink bug abundance, and, at harvest, seed samples were rated for stink bug-induced kernel damage. Individual seeds were categorized as having none, light, moderate, or heavy damage plus 100-seed wt and plot yields were determined. Both ground cloth and sweep net sampling procedures were used to compare stink bug densities between the soybean entries. Stink bug densities varied between years; however, in the years when populations exceeded four per row-meter or six per 25 sweeps, there were more damaged soybean seeds (>25%) in the entries with higher stink bug numbers. During the first 2 yr of evaluations, the mean stink bug-damaged soybean seeds ranged from 10.0 to 38.2%. From these differential responses, 28 entries were selected for continued study in 2003–2004. In 2003, stink bug-damaged soybean seeds were low, with damage ranging from 2.9 to 18.2%. In 2004, stink bug damage ranged from 8.8 to 53.2%. From these 28 lines, 12 entries were selected for an advanced field screening trial in 2005, including the IAC-100 and ‘Hutcheson’. Damaged soybean seeds ranged from 18.5 to 54.1% among these 12 entries in 2005, under heavy stink bug pressure. From these evaluations, four breeding lines with either Hutcheson × IAC-100 or IAC-100 × ‘V71-370′ in their genealogy were identified as possible breeding material for future soybean stink bug resistance cultivar development.

Assessing Stink Bug Resistance in Soybean Breeding Lines Containing Genes from Germplasm IAC-100

Sixty-five soybean, Glycine max (L.) Merr., breeding lines containing the stink bug resistant 'IAC-100' in their pedigrees were evaluated for their resistance to stink bug, primarily southern green stink bug, Nezara viridula L., feeding in replicated field trials from 2001 to 2005. Plots were sampled throughout the season for stink bug abundance, and, at harvest, seed samples were rated for stink bug-induced kernel damage. Individual seeds were categorized as having none, light, moderate, or heavy damage plus 100-seed wt and plot yields were determined. Both ground cloth and sweep net sampling procedures were used to compare stink bug densities between the soybean entries. Stink bug densities varied between years; however, in the years when populations exceeded four per row-meter or six per 25 sweeps, there were more damaged soybean seeds (>25%) in the entries with higher stink bug numbers. During the first 2 yr of evaluations, the mean stink bug-damaged soybean seeds ranged from 10.0 to 38.2%. From these differential responses, 28 entries were selected for continued study in 2003-2004. In 2003, stink bug-damaged soybean seeds were low, with damage ranging from 2.9 to 18.2%. In 2004, stink bug damage ranged from 8.8 to 53.2%. From these 28 lines, 12 entries were selected for an advanced field screening trial in 2005, including the IAC-100 and 'Hutcheson'. Damaged soybean seeds ranged from 18.5 to 54.1% among these 12 entries in 2005, under heavy stink bug pressure. From these evaluations, four breeding lines with either Hutcheson X IAC-100 or IAC-100 x 'V71-370' in their genealogy were identified as possible breeding material for future soybean stink bug resistance cultivar development.

Insects in a warmer world: ecological, physiological and life‐history responses of true bugs (Heteroptera) to climate change

AbstractFocusing on the southern green stink bug, Nezara viridula (Pentatomidae), in central Japan the effects of climate change on true bugs (Insecta: Heteroptera) are reviewed. In the early 1960s, the northern edge of the species's distribution was in Wakayama Prefecture (34.1°N) and distribution was limited by the +5°C coldest month (January) mean temperature isothermal line. By 2000, N. viridula was recorded 70 km further north (in Osaka, 34.7°N). Historical climate data were used to reveal possible causes of the northward range expansion. The increase of mean and lowest winter month temperatures by 1–2°C in Osaka from the 1950s to the 1990s improved potential overwintering conditions for N. viridula. This promoted northward range expansion of the species. In Osaka, adult diapause in N. viridula is induced after mid‐September, much later than in other local seed‐feeding heteropterans. This late diapause induction results in late‐season ineffective reproduction: some females start oviposition in autumn when the progeny have no chance of attaining adulthood and surviving winter. Both reproductive adults and the progeny die. A period from mid‐September to early November represents a phenological mismatch: diapause is not yet induced in all adults, but it is already too late to start reproduction. Females that do not start reproduction but enter diapause in September have reduced postdiapause reproductive performance: they live for a shorter period, have a shorter period of oviposition and produce fewer eggs in smaller egg masses compared with females that emerge and enter diapause later in autumn. To some extent, N. viridula remains maladapted to Osaka environmental conditions. Ecological perspectives on establishment in recently colonized areas are discussed. A review of available data suggests that terrestrial and aquatic Heteroptera species respond to climate change by shifting their distribution ranges, changing abundance, phenology, voltinism, physiology, behaviour, and community structure. Expected responses of Heteroptera to further climate warming are discussed under scenarios of slight (&lt;2°C) and substantial (&gt;2°C) temperature increase.

Toxicity of &lt;I&gt;Chromobacterium subtsugae&lt;/I&gt; to Southern Green Stink Bug (Heteroptera: Pentatomidae) and Corn Rootworm (Coleoptera: Chrysomelidae)

Diabrotica spp. (Coleoptera: Chrysomelidae) beetles and southern green stink bugs, Nezara viridula (L.) (Heteroptera: Pentatomidae), are pests on corn, Zea mays L., and soybean, Glycine max (L.) Merr., as well as on cucurbits. Control of these insects has depended on chemicals. An alternative to chemical control is the use of biologicals. Use of bacteria, fungi, viruses, pheromones, and metabolites to control these insects can potentially improve resistance management and reduce pesticide use. Other than Bacillus thuringiensis Berliner, few bacteria have been discovered that are lethal to either of these pests. Chromobacterium subtsugae Martin et al., a newly described bacterium that is known to be toxic to Colorado potato beetle, Leptinotarsa decemlineata (Say), larvae, was found to be toxic to both diabroticite adult beetles and southern green stink bug adults. In laboratory assays, toxins produced by these bacteria kill 80-100% of the adults of two species of diabroticite beetles, Diabrotica undecimpunctata howardi Barber and Diabrotica virgifera virgifera LeConte, and 100% of southern green stink bug adults within 6 d. For green stink bug, live bacteria were not needed for toxicity.

The Egg Parasitoid Trissolcus basalis uses n-nonadecane, a Cuticular Hydrocarbon from its Stink Bug Host Nezara viridula, to Discriminate Between Female and Male Hosts

Contact kairomones from adult southern green stink bugs, Nezara viridula (L.) (Heteroptera: Pentatomidae) that elicit foraging behavior of the egg parasitoid Trissolcus basalis (Wollaston) were investigated in laboratory experiments. Chemical residues from tarsi and scutella of N. viridula induced foraging by gravid female T. basalis. Residues from body parts of female N. viridula elicited stronger responses than those from the corresponding body parts of males. Deproteinized tarsi still elicited searching responses from wasps, indicating that the kairomone was not proteinaceous. Hexane extracts of host cuticular lipids induced searching responses from T. basalis, with a strong preference for extracts from female hosts. Extracts consisted primarily of linear alkanes from nC19 to nC34, with quantitative and qualitative differences between the sexes. Extracts of female N. viridula contained more nC23, nC24, and nC25 than the corresponding extracts from males, whereas nC19 was detected only in extracts from males. Direct-contact solid phase microextraction (DC-SPME) of N. viridula cuticle and of residues left by adult bugs walking on a glass plate confirmed gender-specific differences in nC19. Trissolcus basalis females responded weakly to a reconstructed blend of the straight-chain hydrocarbons, suggesting that minor components other than linear alkanes must be part of the kairomone. Addition of nC19 to hexane extracts of female N. viridula significantly reduced the wasps' arrestment responses, similar to wasps' responses to hexane extracts of male hosts. Overall, our results suggest that a contact kairomone that elicits foraging by T. basalis females is present in the cuticular lipids of N. viridula, and that the presence or absence of nC19 allows T. basalis females to distinguish between residues left by male or female hosts. The ecological significance of these results in the host location behavior of scelionid egg parasitoids is discussed.