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New associations are reported between the parasitoid Habrobracon hebetor (Say) and two genera of postharvest pest coleopters on shelled fruits of Juglans regia L, Carpophilus Stephens (Nitidulidae) and Oryzaephilus Ganglbauer (Silvanidae) in the province of La Rioja. Furthermore, this parasitoid was recorded from larvae of Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae). The distribution of H. hebetor is expanded to the province of La Rioja. Data on percentages of parasitoidism are provided. [ABSTRACT FROM AUTHOR]

The data on biology and taxonomy of the new subspecies Bracon pallicarpus dorytomovorus Samartsev & Dokuchaev ssp. nov. are given. It was shown that in the Northern Okhotsk region, the wasps of the new subspecies are solitary univoltine parasitoids of the Dorytomus cinereus Hochhuth, 1851 (Coleoptera, Curculionidae) larvae which feed on the central axis of the catkins of the willow Salix rorida Lakschevitz (Salicaceae). Having consumed the weevil larva, the parasitoid forms a cocoon inside the host's tunnel and overwinters as a pupa inside the fallen catkin. Bracon pallicarpus dorytomovorus ssp. nov. adults emerge the next year in the second half of May. The status of the specimens of the type series of B. pallicarpus pallicarpus Thomson, 1892 was specified and its differences from 30 closely related species are presented. Bracon schmiedeknechti Fahringer, 1927 was synonymised with B. pallicarpus pallicarpus (syn. nov.). [ABSTRACT FROM AUTHOR]

The lepidopteron leafminers are considered as serious pests of economic importance world widely. In rearing of lepidopteran leafminers viz., Acrocer-cops phaeospora Meyr. and Cosmopterix phaeogas-tra (Meyr.) and Cameraria virgulata (Meyr.) (Lepi-doptera: Gracillariidae) from various host plants in northern India; three species of parasitoids viz., Bra-con acrocercophagus Ahmad and Pandey, sp. nov., Brocon cosmopteryx Ahmad and Pandey, sp. nov., and Bracon virgulatae Ahmad and Pandey, sp. nov., (Hymenoptera: Braconidae) were observed. All three species are described as new to science and data on habitat, brief diagnoses and host records for all parasitoids species are provided. Data related with all braconine species associated with leafminers is also provided. [ABSTRACT FROM AUTHOR]

A survey of Braconinae wasps was conducted at five sites, represented by various agroecosystems, rangelands and forests in Western Iran (Hamadan province) during 2015−2016 with a series of light and Malaise traps. Fifteen species belonging to three genera (Bracon Fabricius, Glyptomorpha Holmgren and Pseudovipio Szépligeti) were identified, among them five species, viz. Bracon concavus Tobias, B. fumigidus Szépligeti, B. iskilipus Beyarslan & Tobias, B. moczari Papp and B. novus Szépligeti, were recorded for the first time from Iran. 15 species are new provincial records for Hamadan.

The antibiosis effect of gallic acid on Spodoptera litura F. (Lepidoptera: Noctuidae) and its parasitoid evaluated by feeding six days old larvae on artificial diet incorporated with different concentrations (5 ppm, 25 ppm, 125 ppm, 625 ppm, 3125 ppm) of the phenolic compound revealed higher concentration (LC50) of gallic acid had a negative impact on the survival and physiology of S. litura and its parasitoid Bracon hebetor (Say) (Hymenoptera:Braconidae). The mortality of S. litura larvae was increased whereas adult emergence declined with increasing concentration of gallic acid. The developmental period was delayed significantly and all the nutritional indices were reduced significantly with increase in concentration. Higher concentration (LC50) of gallic acid adversely affected egg hatching, larval mortality, adult emergence and total development period of B. hebetor. At lower concentration (LC30) the effect on B. hebetor adults and larvae was non-significant with respect to control. Gene expression for the enzymes viz., Superoxide dismutase, Glutathione peroxidase, Peroxidase, Esterases and Glutathione S transferases increased while the total hemocyte count of S. litura larvae decreased with treatment. Our findings suggest that gallic acid even at lower concentration (LC30) can impair the growth of S. litura larvae without causing any significant harm to its parasitoid B. hebetor and has immense potential to be used as biopesticides. [ABSTRACT FROM AUTHOR]

Background: Cotton bollworms such as Pectinophora gossypiella and Earias insulana are serious pests which destroy the cotton plant, and Bracon brevicornis is a parasitoid which attacked the larvae of bollworms. Results: In this study, experiments were performed to investigate and evaluate the toxicity of etofenprox and chlorpyrifos insecticides against newly hatched larvae of Pectinophora gossypiella and Earias insulana. Some biological aspects of compound effects on larval and pupal duration, percentage of mortality, and percentage of adult emergence which resulted from treated newly hatched larvae were studied. The results revealed that LC50 was 0.7 and 0.87 ppm when P. gossypiella was treated with etofenprox and chlorpyrifos, respectively, while LC50 was 0.09 and 0.73 ppm when E. insulana was treated with etofenprox and chlorpyrifos, respectively. The obtained results showed that the percentage of mean larval mortality was 65.0 and 63.0% for treated P. gossypiella, while it was 71.0 and 66.0% for treated E. insulana. The corresponding figure for pupal percentage mortality was 8.0 and 10.0% for treated P. gossypiella, but it was 5.0 and 2.0% for treated E. insulana, with etofenprox and chlorpyrifos, and a prolongation effect in larval and pupal development (total immature stage) resulted from treated both bollworms as follows: 35.5 and 32.4 days for treated P. gossypiella compared with 21.9 days in control and 34.7 and 23.2 days for treated E. insulana compared with 23.1 days in control. The indirect effect of etofenprox and chlorpyrifos on the total immature stage of Bracon brevicornis was 18.2 and 19.5 days compared with 14.3 days in control when B. brevicornis parasitized on P. gossypiella larvae while it was 19.8 and 20.6 days compared with 15.2 days when B. brevicornis parasitized on E. insulana larvae. Conclusion: The life cycle of B. brevicornis after parasitism on P. gossypiella and E. insulana larvae treated with etofenprox and chlorpyrifos were increased than the control larvae. [ABSTRACT FROM AUTHOR]

1. Mutualisms are relationships of mutual exploitation, in which interacting species receive a net benefit from their association. In obligate pollination mutualisms (OPMs), female pollinators move pollen between the flowers of a single plant species and oviposit eggs within the female flowers that they visit. 2. Competition between co‐occurring pollinator species is predicted to increase pollinator virulence, i.e. laying more eggs or consuming more seeds per fruit. Plants involved in OPMs frequently host various non‐pollinating seed parasites and parasitoids that may influence the outcome of the mutualism. Quantifying the prevalence of parasites and parasitoids and competition between pollinators is important for understanding the factors that influence OPM evolutionary stability. 3. This study investigated the pollination mutualism occurring between the leaf flower plant, Breynia oblongifolia, and its co‐pollinating Epicephala moths. A third moth, Herpystis, also occurs in B. oblongifolia fruits as a non‐pollinating seed parasite. 4. Breynia oblongifolia fruits were collected to quantify seed predation and compare seed predation costs between the three moth species. Results showed that the larvae of the two pollinator species consume similar numbers of seeds, and that adults deposit similar numbers of eggs per flower. As such, no evidence of increases in virulent behaviours was detected as a result of competition between co‐pollinators. 5. By contrast, the seed parasite Herpystis consumed more seeds than either pollinator species, and fruit crops with a high proportion of Herpystis had significantly lower net seed production. 6. This work adds to the growing understanding of the ecology and dynamics of plant–pollinator mutualisms. [ABSTRACT FROM AUTHOR]

The yield losses in pearl millet, estimated to be about 85%, are mainly due to millet headminer, Heliocheilus albipunctella. This study is aimed at determining the status of this serious insect pest in the pearl millet production system within the groundnut basin of Senegal and to assess the efficacy of augmentative releases of its parasitoid wasp, Bracon hebetor, to control it. The study area was divided into three homogenous blocks (Northern, Southern and Eastern parts) where a set of three villages was selected for release of the parasitoid and another three as control villages where no releases were made. The results revealed that in all the villages where the parasitoid was released, an increase in larval mortality due to parasitism ranging between 9% and 26% was recorded in comparison with the control villages. Consequently, damages recorded were significantly lower in the villages with parasitoid releases. [ABSTRACT FROM AUTHOR]

Habrobracon hebetor (Say 1836) is an important biological control agent around the world. Many hundreds of papers have been published about its biology. Due to the global distribution of H. hebetor many species have been described over the years in various countries as a sister species to H. hebetor but were eventually synonymized with H. hebetor. One of which is Habrobracon brevicornis (Wesmael 1838). Here, we revalidate the status of H. brevicornis stat. rest. based on molecular data. It remains difficult to discriminate the two species based on morphology data alone, but with molecular data the differentiation is straight forward. An integrative key is provided to distinguish H. hebetor from H. brevicornis. [ABSTRACT FROM AUTHOR]

Insect-derived volatiles seem to provide reliable chemical cues that plants could employ to defend themselves. Here we investigated the effect of pheromone emission from a closely associated (Anthonomus grandis ; boll weevil) and an unassociated (Tibraca limbativentris) herbivore on cotton volatile emission. Exposure to A. grandis aggregation pheromone induced cotton defence response by enhancing the emission of volatiles attractive to the natural enemy of A. grandis, the parasitic wasp Bracon vulgaris, but only when the pheromonal blend was complete (all four components). Individual components of A. grandis aggregation pheromone were not able to induce cotton plants to increase the release of volatiles. On the other hand, T. limbativentris sex pheromone did not induce any change in the cotton constitutive volatile profile. Our results support the hypothesis that plants are able to detect pheromones of tightly co-evolved herbivores. Moreover, A. grandis pheromone exposure induced similar volatile compounds to herbivore-induced cotton, such as linalool, (E)-ocimene, (E)-4,8-dimethylnona-1,3,7-triene (DMNT), and (E,E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene (TMTT). We also showed that the larval ectoparasitoid B. vulgaris relies on boll weevil's aggregation pheromone and pheromone-induced plant volatiles as kairomones to locate suitable hosts. [ABSTRACT FROM AUTHOR]

Purple prairie clover (Dalea purpurea Vent.) is a perennial legume native to prairies throughout the central USA and Canada. Seed set in natural populations can be very low, and the reasons are not well known. Our objectives were: 1) describe the reproductive morphology in natural populations of purple prairie clover, 2) identify seed predators and parasitoids associated with natural populations, and 3) determine seed set in natural and cultivated populations of purple prairie clover in eastern SD. Inflorescences were collected from natural and cultivated populations on the South Dakota State University Oak Lake Field Station (OLFS), a cultivated population near Aurora, SD, and from a cultivated population in McCrory Gardens at Brookings, SD. In natural populations at OLFS, normal seed set was ca. 10%, frequency of unfertilized ovules was ca. 20%, and seed predation was ca. 15%. The most easily verifiable seed predator was Acanthoscelides seminulum (Horn). However, the most common insects on the spikes were adults of Kissingeria capitone (Kissinger) and larvae of an unidentified gall midge of genus Contarinia (Cecidomyiidae). The overwhelmingly most common seed predators in the cultivated populations were K. capitone and Contarinia sp. The most common parasitoid reared from beetle larvae was Eurydinoteloides incerta (Ashmead). The chalcidoid wasps Baryscapus sp. and Aprostocetus marylandensis (Girault) parasitized gall midge larvae, with Baryscapus sp. the most abundant by far. In addition, a few individuals of Bracon sp. and Inostemma sp., hosts unknown, were collected from immature inflorescences. Normal seed set in the McCrory Gardens population was 55% compared with <15% in the other cultivated populations. This study identified a previously unknown guild of insects associated with inflorescences in purple prairie clover and revealed probable reasons for a paucity of viable seed production in natural and cultivated populations. [ABSTRACT FROM AUTHOR]

Rapid population growth and wide host range make Habrobracon hebetor Say (Hymenoptera: Braconidae) highly suitable for biological control programs. To improve performance of the reared wasps in biological control programs we conducted a series of experiments on the effect of mating and carbohydrate feeding on life-history traits of this parasitoid. Mating caused a significant cost to fecundity, host paralysis and parasitism ability of H. hebetor. Mated wasps produced 30.98 and 23.2% less progeny than virgin wasps in unfed and fed treatments, respectively. Carbohydrate feeding increased survival only in the absence of host larvae. Virgin wasps produced only male offspring while the sex ratio produced by mated females was close to 50/50 for both fed and unfed wasps. Virgin wasps demonstrated an aggressive parasitism behavior and significantly higher paralysis and parasitism rates compared to mated wasps. Virgin wasps fed with carbohydrate found significantly more hosts than unfed wasps. To conclude, mating disruption in H. hebetor resulted in an aggressive parasitism behavior in the laboratory, which may also occur in the field. Therefore mating disruption is expected to improve the efficacy of these parasitoids in biocontrol. Carbohydrate feeding only improved searching ability and host allocation and could be applied in situations where hosts are highly dispersed. [ABSTRACT FROM AUTHOR]

The Indian meal moth Plodia interpunctella became a major pest in bulk grain storage in Germany in recent years. Monitoring with adhesive pheromone-baited traps revealed a dependence of the number of generations of the moth from the temperature conditions in store, which themselves depend on insulation of the storage structure. The larval parasitoid Habrobracon hebetor was monitored with the help of cone traps placed in the grain. Baiting these traps with moth webbings significantly increased the number of female wasps trapped in 5 cm depth in wheat. Field trials showed both the pest and the beneficial can be monitored in stores, but more research is needed to develop a biological control strategy for P. interpunctella. [ABSTRACT FROM AUTHOR]

A field experiment of 4 years' duration was carried out to evaluate the efficacy of combining the mating disruption (MD) formulation Dismate ZETA (9Z,12E-tetradecadienyl acetate), with the parasitoid Habrobracon hebetor against the Indianmeal moth Plodia interpunctella in a chocolate factory. The experimental period began early in 2011 and ended in late 2014. Begane Dismate dispensers were placed in the facility from 2011 to 2014 and H. hebetor was released in 2014. Pheromone-baited traps were used to monitor the flight activity of the male moths and oviposition Petri dish cups were placed to assess the progeny production of P. interpunctella females. Following the start of MD, a decrease in the number of P. interpunctella males caught in monitoring traps was observed from 2011 to 2013. A further decline in the moth population was noted in 2014, when MD was combined with the release of parasitoids. The presence of larvae in the oviposition cups was occasionally observed throughout the monitoring period, from 2011 to 2014. This study demonstrates that the combined system of MD and parasitoids is an effective and reliable technique that can be used to successfully control P. interpunctella. [ABSTRACT FROM AUTHOR]

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Host mortality and progeny production by the ectoparasitoid, Habrobracon hebetor Say (Hymenoptera: Braconidae) on diapausing and nondiapausing larvae of Plodia interpunctella Hübner (Lepidoptera: Pyralidae) were investigated in response to peanut depths and free space at standard environmental conditions. The free space was created by having four different quantities of peanuts in glass containers of fixed volume or same quantity of peanut in containers of different sizes. Host mortality caused by the parasitoids was significantly higher for diapausing larvae compared with nondiapausing larvae at corresponding peanut depth. Differences in peanut depth affected mortality of nondiapausing larvae exposed to parasitoids but diapausing larvae experienced the same level of mortality. Regardless of container sizes, host mortality was higher than 90.0% for both types of larvae. When equivalent peanut depths were compared, more F1 parasitoids were produced on diapausing larvae than on nondiapausing larvae. Reduced peanut depth affected the sex ratio of parasitoid progeny reared on nondiapausing larvae but not those reared on diapausing larvae. Parasitoid progeny resulting from reduced peanut depth was male-biased and this was more evident with parasitoids that emerged from diapausing host larvae than nondiapausing larvae. Progeny production by H. hebetor was not influenced by container size. This study underscores the fact that host mortality caused by H. hebetor at different peanut depths was significantly different for nondiapausing host larvae, but was not so for diapausing larvae. The container sizes did not affect the performance of H. hebetor in killing P. interpunctella. The entire study emphasizes the potential of diapausing larvae for the rearing of H. hebetor. [ABSTRACT FROM AUTHOR]

Abstract: Females of the ectoparasitoid Habrobracon hebetor attack and envenomate numerous host individuals during oviposition. The vectoring of the entomopathogenic fungus Beauveria bassiana during the adhesion stage by ectoparasitoid females among the wax moth larvae Galleria mellonella was explored under laboratory conditions. Vectoring occurred both from infected parasitoids to wax moth larvae and from infected to healthy wax moth larvae by parasitoids. The efficacy of vectoring in both cases was dose dependent. Parasitoid females were unable to recognize infected larvae in a labyrinth test. In addition, the presence of H. hebetor females significantly (1.5–13 fold) increased the mycoses level in clusters of G. mellonella, with 40% of the larvae infected with fungal conidia. Envenomation by H. hebetor increased conidia germination on the cuticles of the wax moth larvae by 4.4 fold. An enhanced germination rate (2 fold) was registered in the n‐hexane epicuticular extract of envenomated larvae compared to that of healthy larvae. Both envenomation and mycoses enhanced the phenoloxidase (PO) activity in the integument of G. mellonella and, in contrast, decreased the encapsulation rate in hemolymphs. We hypothesize that changes in the integument property and inhibition of cellular immunity provide the highest infection efficacy of entomopathogenic fungi with H. hebetor. [ABSTRACT FROM AUTHOR]

Habrobracon hebetor (Say) is a parasitoid of various Lepidoptera including Helicoverpa armigera (Hübner), a key pest of different crops and vegetables. The development of both H. armigera and H. hebetor were simultaneously evaluated against a wide range of constant temperatures (10, 15, 17.5, 20, 25, 27.5, 30, 35, 37.5 and 40 °C). Helicoverpa armigera completed its development from egg to adult within a temperature range of 17.5–37.5 °C and H. hebetor completed its life cycle from egg to adult within a temperature range of 15–40 °C. Based on the Ikemoto and Takai model the developmental threshold (To) and thermal constant (K) to complete the immature stages, of H. armigera were calculated as 11.6 °C and 513.6 DD, respectively, and 13 °C and 148 DD, respectively, for H. hebetor. Analytis/Briere-2 and Analytis/Briere-1 were adjudged the best non-linear models for prediction of phenology of H. armigera and H. hebetor, respectively and enabled estimation of the optimum (Topt) and maximum temperature (Tmax) for development with values of 34.8, 38.7, 36.3, and 43 °C for host and the parasitoid, respectively. Parasitisation by H. hebetor was maximal at 25 °C but occurred even at 40 °C. This study suggests although high temperature is limiting to insects, our estimates of the upper thermal limits for both species are higher than previously estimated. Some biological control of H. armigera by H. hebetor may persist in tropical areas, even with increasing temperatures due to climate change. [ABSTRACT FROM AUTHOR]

Cold storage can extend shelf life of parasitoids for use in biocontrol. However, cold storage may have negative impacts on life history traits of the parasitoids and, therefore, on their performance as biocontrol agents. Here, we examine the effect of cold storage on life history traits of Habrobracon hebetor (Say) (Hymenoptera: Braconidae), a parasitoid of several economic lepidopteran pests. Newly emerged wasps were stored at three constant temperatures (3°C, 5°C, 7°C) for up to 4 wk. Both temperature and exposure time significantly affected longevity, parasitism, fecundity, and sex ratio. Significant reduction in longevity was observed at 3°C and 7°C, whereas longevity of wasps stored at 5°C remained stable up to the second week and then gradually decreased in Weeks 3 and 4. Parasitism rate also significantly decreased after cold storage at 3°C, 5°C, and 7°C (ranked from high to low). Fecundity decreased at T 3°C and T 5°C but this trait was not affected by storage at T 7°C. A significant shift in male production was observed at T 5°C in Week 3, but in Week 4, the only treatment with male biased reproduction was T 3°C. These results show that the effect of temperature and exposure time in cold storage is trait dependent. Overall, storage at 5°C for a period of 3 wk least impacted most life-history traits of H. hebetor wasps. [ABSTRACT FROM AUTHOR]

The major obstacle to the adoption of Habrobracon hebetor (Say) (Hymenoptera: Braconidae) for the management of postharvest moth pests is the short duration of the last instar stage of the hosts, which is the preferred stage by the parasitoid for development. It is postulated that mass rearing of the parasitoid on diapausing larvae is possible due to arrested development of the last instar of Pyralid hosts that offers the parasitoid a wider window to paralyze host larvae. Laboratory studies were conducted to evaluate the rearing of H. hebetor on diapausing and non-diapausing larvae of Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae) at standard environmental conditions. Host mortality of 100% was observed at nearly all larval densities of diapausing larvae but in non-diapausing larvae, the percentage mortality consistently decreased with increase in host density. More progeny of H. hebetor was produced on diapausing larvae than on non-diapausing larvae. Weights of female parasitoid progeny were highest at host density of 10 for diapausing larvae and not significantly different for males. The number of adults from eggs laid by mated female wasps provisioned daily with fresh diapausing larvae up to 5th day was significantly higher than those by parasitoids provisioned with non-diapausing larvae. The maximum number of adults that completed development from eggs laid daily by H. hebetor provisioned with diapausing larvae was on the 3rd day but those provisioned with non-diapausing larvae was on the 5th day. The results from this study show that diapausing larvae of P. interpunctella will be ideal for mass rearing of H. hebetor for the management of Pyralid populations. [ABSTRACT FROM AUTHOR]

Pest control in the agricultural fields, a major concern globally, is currently achieved through chemical or biological methods. Chemical methods, which leave toxic residue in the produce, are less preferred than biological methods. Venoms injected by stings of various wasps that kill the pest is considered as the examples of the biological method. Although several studies have investigated the biological control of pests through these venoms, very few studies have reported the effects of these venoms on mammalian cells. Bracon hebetor, an ectoparasitoid of the order Hymenoptera, is having a paramount importance in parasitizing various lepidopterous larvae including Plodia interpunctella also called as Indianmeal moth (IMM). Since it is biologically controlled by B. hebetor venom, therefore in our study, herein for the first time, we report the anti-inflammatory activities of the venom from B. hebetor (BHV). We developed a septic shock mice model for in vivo anti-inflammatory studies and RAW 264.7 cells for in vitro studies. Our results clearly demonstrate that BHV can dose dependently abrogate the nitric oxide (NO) production and suppress the levels of proinflammatory mediators and cytokines without posing any cytotoxicity via the nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways. [ABSTRACT FROM AUTHOR]

Habrobracon hebetor Say is an ectoparasitoid that has been used as a control agent of various lepidopteran pests. Temperature-dependent life table and thermal characteristics of H. hebetor are important in understanding the dynamics of host–parasitoid relationships and for optimizing biocontrol programmes. The influence of five constant temperatures (15, 20, 25, 30 and 35 °C) on the biology of H. hebetor when parasitizing Anagasta kuehniella Zeller was studied. The survival rate of immature stages increased from 16.67% to 83.81% as temperature increased from 15 to 30 °C and then decreased at 35 °C. Total development time ranged from 45.70 days at 15 °C to 7.10 days at 35 °C. The lower temperature threshold for immature stages varied slightly around a value of 11–12 °C. The net reproductive rate (R0) values were significantly different among temperatures and the highest value was found at 30 °C (85.10). The high survival rate and net reproductive rate combined with a relatively short generation time at 30 °C resulted in the intrinsic rate of increase (rm) being highest (0.312 d−1) at this temperature. Considering the acquired results, the temperature range between 25 and 30 °C was optimal for H. hebetor. [ABSTRACT FROM AUTHOR]

Habrobracon hebetor (Say) is a cosmopolitan idiobiont braconid which parasitizes Pyralidae larvae, a pest of stored products, such as Ephestia kuehniella (Zeller). The objective was to describe the morphology of immature forms of H. hebetor and morphological changes throughout its development. Mated females of H. hebetor were individualized in Petri dishes containing larvae of E. kuehniella for parasitism for six hours. Then, the females were removed, leaving only the eggs placed on the host. The development was evaluated every 12 hours, recording all stages and changes until the emergence of adults. Using stereoscopic optical and scanning electron microscopy, photographs of immature individuals were taken. The results showed that this parasitoid completes its development between 10-12 days. There were stages overlaps during egg to adult development. Eggs are hymenopteriform, with a smooth surface. According to cephalic capsule and larval length measurements of H. hebetor, it was possible to determine four instars. In general, the instars are similar to each other, differing mainly in the size and shape of segments. Larvae present a gradual loss of transparency, becoming opaquer at each successive instar. Last instar larvae distanced from the host to form the cocoon and to pupate. This study was relevant for a better understanding of the physiological interactions between E. kuehniella and H. hebetor. [ABSTRACT FROM AUTHOR]

A faunistic survey of the genera Bracon Fabricius, 1804 and Habrobracon Ashmead, 1895 was carried out in some parts of northern (Guilan Province), northeastern (North Khorasan Province), eastern (Khorasan-e Razavi and Sistan-o Baluchestan provinces), south-central (Kerman Province), central (Isfahan Province), and western (Kermanshah Province) Iran during 2011-2014. Sampling was done in various agroecosystems and rangelands. In total, 28 species were collected and identified, of which 8 species are recorded for the fauna of Iran for the first time: Bracon alutaceus Szépligeti, 1901; B. (Osculobracon) bilgini Beyarslan, 2002; B. byurakanicus Tobias, 1976; B. marshalli Szépligeti, 1901; B. murgabensis Tobias, 1957; B. (O.) minutus Szépligeti, 1901; B. parvicornis Thomson, 1892; and B. roberti Wesmael, 1838. Bracon bipartitus Wesmael, 1838 and B. (O.) minutus Szépligeti, 1901 are revalidated as separate species. New synonymy is suggested for Bracon rozneri Papp, 1998 syn. nov. and Bracon variator var. chinensis syn. nov. with Bracon bipartitus, and for Bracon chagrinicus Beyarslan, 2002 syn. nov. with B. (O.) minutus. Brief diagnoses are presented for the newly recorded species, as well as for B. bipartitus; B. chrysostigma Greese, 1928; and B. femoralis (Brullé, 1832). [ABSTRACT FROM AUTHOR]

The host regulation process has been widely investigated in endophagous parasitoid wasps, which in most cases finely interact with living hosts (i.e. koinobiont parasitoids). In contrast, only very limited information is available for ectophagous parasitoids that permanently paralyze and rapidly suppress their victims (i.e. idiobiont parasitoids). Here we try to fill this research gap by investigating the host regulation by Bracon nigricans , an ectophagous idiobiont wasp species. Parasitism, mainly by venom action, is able to redirect host metabolism in order to enhance its nutritional suitability for the developing parasitoid larvae and to provide the required metabolic support to host tissues. The observed alterations of the host titers of haemolymph proteins, carbohydrates and acylglycerols are associated with a parasitoid-induced mobilization of nutrients stored in the fat body. This tissue undergoes a controlled degradation mediated by a close surface interaction with haemocytes, where a cathepsin L activity is localized, as demonstrated by immunolocalization, biochemical and transcriptional data . B. nigricans parasitism does not markedly influence the survival of haemocytes, even though a persistent suppression of the immune competence is observed in parasitized hosts, which show a reduced capacity to encapsulate and melanize non-self objects. These immune alterations likely allow a more efficient food uptake and use by the ectophagous larvae. The obtained results indicate that the host regulation process in basal lineages of parasitic Hymenoptera is more complex than expected and shares functional similarities with adaptive strategies occurring in derived koinobiont species. [ABSTRACT FROM AUTHOR]

To assess the potential of the hymenopteran ectoparasitoid,Habrobracon hebetorSay as a biological control agent, we evaluated its response to different larval densities of two pyralid hosts,Palpita unionalisHbn. andGalleria mellonellaL. The former host is a serious pest of olive trees, whereas the latter is used as a factitious host in parasitoid mass rearing. In order to study the functional response of the parasitoid, five host densities (1, 2, 3, 5, 7) of either late instar larva per Petri dish were used. The shape of the functional response curve was determined using logistic regression and could be described as a type II response for both hosts, characterised by a monotonic decelerating increase in the number of hosts attacked with increasing host density. Female parasitoids allocated more eggs to the first larva attacked than all the remaining larvae. Aggregated dispersion patterns for parasitoid egg distribution at different host densities were estimated using the Green index. Multiple visits and ovipositions by females did not significantly affect the total number of progeny produced or their sex ratio. This study has generated novel information on egg laying, egg distribution and sex ratio ofH. hebetorwhen reared onG. mellonellaand has the potential to be used in the development of sustainable biological control programmes aimed atP. unionalisin olive orchards. [ABSTRACT FROM PUBLISHER]

Gregarious parasitic wasps, which lay more than one egg into or onto a host arthropod's body, are usually assumed to lay an optimal number of eggs per host. If females would lay too few eggs, some resources may be wasted, but if females lay too many eggs, offspring may develop into substantially smaller-sized adults or may not develop successfully and die. The availability of hosts can further influence a female's clutch size decision, as more eggs should be laid when hosts are scarce. Here, we analyzed clutch size decisions and the fitness consequences thereof in the ectoparasitic wasp Bracon brevicornis (Hymenoptera: Braconidae), a potential biocontrol agent against pest moth species. For experiments, larvae of the Mediterranean flower moth, Ephestia kuehniella (Lepidoptera: Pyralidae) were used. Using artificially created as well as naturally laid clutches of eggs, the effects of clutch size on fitness of first (F1) and second (F2) generation offspring were investigated. Our results revealed that the fitness consequences of large clutches included both increased mortality and smaller adult sizes of the emerging offspring (F1). Smaller F1 females matured fewer eggs during their lifetime and their offspring (F2) had reduced egg-to-adult survival probability. Naturally laid clutches varied with host size up to a maximum, which probably reflects egg limitation. Clutches remained smaller than the calculated optimal (Lack) clutch size and females responded to high host availability with a decreased number of eggs laid. We thus conclude that large clutches may result in significantly smaller offspring with reduced fitness, and that host size as well as host availability influence the clutch size decision made by B. brevicornis females. [ABSTRACT FROM AUTHOR]

We evaluated the susceptibility of Galleria mellonella larvae immunosuppressed by the venom of Habrobracon hebetor to soil entomopathogenic ascomycetes with the use of bait method. It was found that the sensitivity of the modified method was significantly (by almost 200 times) increased as compared with the standard procedure, which provided the isolation of fungi when their abundance was extremely low. Envenomated larvae were more susceptible to the entomopathogenic but not saprotrophic fungi. We presented results of isolation of the entomopathogenic fungi from soils in different climatic zones (from the forest tundra to the steppe) using an improved procedure. [ABSTRACT FROM AUTHOR]

A field experiment of 4 years' duration was carried out to evaluate the efficacy of combining the mating disruption (MD) formulation Dismate ZETA ((9 Z,12 E)-tetradecadienyl acetate), with the parasitoid Habrobracon hebetor against the Indianmeal moth Plodia interpunctella in a chocolate factory. The experimental period began early in 2011 and ended in late 2014. Begane Dismate dispensers were placed in the facility from 2011 to 2014 and H. hebetor was released in 2014. Pheromone-baited traps were used to monitor the flight activity of the male moths and oviposition Petri dish traps were placed to assess the progeny production of P. interpunctella females. Following the start of MD, a decrease in the number of P. interpunctella males caught in monitoring traps was observed from 2011 to 2013. A further decline in the moth population was noted in 2014, when MD was combined with the release of parasitoids. The presence of larvae in the oviposition cups was occasionally observed throughout the monitoring period, from 2011 to 2014. This study demonstrates that the combined system of MD and parasitoids is an effective and reliable technique that can be used to successfully control P. interpunctella. [ABSTRACT FROM AUTHOR]

Bracon variator Nees, is a larval ectoparasitoid of Cydia johanssoni Aarvik & Karsholt, a major seed feeder of Stinking bean trefoil, Anagyris foetida L. (Leguminosae) at forest habitats in Gilan-e Gharbe, Kermanshah, Western parts of Iran. This investigation was conducted during spring 2014, in order to determine the most important parasitoid of pest larvae, the rate of parasitism and to study some biological aspects. The ectoparsitoid prefers 3rd to 5th instar larvae. Host development was arrested immediately upon parasitism. Each adult female laid three eggs close to host larvae, inside seed case. It had two generations per year. Both aestivation and hibernation of the parasitoid occur in the form of prepupa in cocoon inside infested seeds. Adult activity of first and second generation was observed in the beginning and ending of May, respectively. The average of parasitism rate of second generation was calculated 18.77±3.80. Cydia johanssoni larvae, as a host of Bracon variator, has been recorded for the first time. [ABSTRACT FROM AUTHOR]

Biological control by augmentative releases of the parasitoid wasp Habrobracon hebetor Say (Hymenoptera: Braconidae) is a promising strategy for controlling the millet head miner (MHM), Heliocheilus albipunctella (de Joannis) (Lepidoptera: Noctuidae). A current biological control program in the Sahel region involves inoculative releases of the parasitoid each growing season, but this is prohibitively expensive. The present study aimed to quantify residual parasitism of MHM in years after augmentative release. We also investigated the impact of two successive annual releases of H. hebetor on MHM parasitism. Two successive releases did not increase parasitism, but slightly reduced MHM damage in terms of number of mines and their length. Parasitism levels decreased in subsequent years if no additional parasitoids were released. Nevertheless, in the first year after release, parasitism levels in release villages remained significantly higher than in control villages. These findings suggest that augmentative releases could be carried out biennially instead of annually. Possible means of enhancing parasitoid survival between seasons are discussed. [ABSTRACT FROM AUTHOR]

The ecto-larval parasitoid, Bracon hebetor (Say) (Hymenoptera: Braconidae) is an important biocontrol agent of pyralid lepidopterous pests. The effect of long-term cold storage of the parasitoid wasps as well as the larvae of its factitious host, Galleria mellonella L. (Lepidoptera: Pyralidae) was investigated. Both were stored at 12°C for different durations extended to 4 months. Both were weekly subjected to room temperature for about 3 hrs and parasitoid was provided with honey droplets for feeding. Wasps' mortality increased as storage duration (0, 1, 2, 3 and 4 months) increased and males showed higher percentages of mortality than females. Female mortality exceeded 50% as the storage period went beyond 3 months. Longevity of adult females, survival of immature stages and sex ratio of progeny didn't differ significantly along different storage durations. On the other hand, the long term exposure to chilliness regime showed a significant reduction in the number of deposit eggs. Also, the ability of the parasitoid wasps to either paralyze or parasitize host larvae was slightly affected by cold storage. When host larvae were stored for the same durations, then subjected to 1 day old parasitoid wasps, there was a slight difference in the rate of parasitism. The number of deposit eggs on each stored larva significantly differed from culture larvae. Egg hatching of larvae stored for different durations, survival of both larvae and pupae were of the same rate as the control. Sex ratio of progeny was almost similar to that recorded in control. It is clear from the previous observations that storing the parasitoid wasps and host larvae using the pre-described regime could be helpful to provide sufficient numbers of both when they are in need either for mass rearing in the laboratory or for field release. This could obviously support the continuity of the culture and save the cost of rearing during times of low demand of the parasitoid. [ABSTRACT FROM AUTHOR]

Habrobracon hebetor Say ( Hymenoptera: Braconidae) is a cosmopolitan idiobiont ectoparasitoid wasp and one of the most important biological control agents of lepidopteran larvae, especially of larvae of the family Pyralidae such as Indian meal moth, Plodia interpunctella ( Hübner). Using biological control agents in combination with other pest management approaches may enhance the efficiency of pest management. Acarbose, a non-proteinaceous inhibitor, is well known for its inhibitory effect on insect digestive carbohydrases, especially α-amylase. In the present study the effect of the inhibitor on various physiological and biological parameters of the parasitoid H. hebetor was investigated in a diet-host-parasitoid tritrophic system. The inhibitor decreased α-amylase activity in both in vitro and in vivo assays with the parasitoid; however, there was no significant impact on the biological characteristics studied. Quantification of energy reserves in host larvae and adult parasitoids revealed a dose-dependent effect of the inhibitor on total protein, lipid, carbohydrate, and glycogen contents of the larval host, whereas total protein and carbohydrate of the parasitoid were only reduced at high inhibitor concentrations. In general, the inhibitor acarbose can interfere with some physiological processes in H. hebetor, although the parasitoid's fitness is not negatively affected. Therefore, enzyme inhibitors may be considered an effective tool for pest control in integrated pest management programs. [ABSTRACT FROM AUTHOR]

The study describes the effects of parasitism of Bracon hebetor (Say) (Hymenoptera: Braconidae), on yields of Steinernema carpocapsae (Rhabditida: Steinernematidae) in the greater wax moth larvae, Galleria mellonella (L.) (GWM). B. hebetor eggs and/or larvae at a range densities of 0,1-2, 3-5 and 6-8 wasps /GWM larvae were tested concerning their effect on final body weight and nematode production. The final weight of paralyzed larvae was severely depressed following parasitization by B. hebetor and was wasp stage and wasp number-dependent. Nematode production decreased as the wasp densities increased. The nematode yields were higher in non-parasitized GWM larvae than in parasitized larvae. [ABSTRACT FROM AUTHOR]

In his monograph Wesmael (1838) made a survey of 48 Bracon Fabricius species occurring in Belgium. Out of the 48 species 37 have been described by Wesmael himself as new species, the rest of the species, 11 ones, divides among three authors: seven species by Nees, three species by Fabricius and one species by Spinola. Type (holo-, lecto-, paralectotype) designations of Wesmael’s species and neotype designations of Nees sensu Wesmael’s species are accomplished accompanied with their redescriptions, distributions and taxonomic positions. The Bracon material studied by Wesmael is deposited in Institut royal des Sciences naturelles de Belgique, Bruxelles. Palpibracon new subgenus is established for four Bracon species with long maxillar palp in the Holarctic Region. Fourteen species names proved to be junior synonyms. The species Bracon turolus Papp is revalidated. The subgeneric division of the Bracon species is briefly discussed.

This is the first checklist of the genus Bracon for the territory of Serbia. Here we present 80 species of this cosmopolitan genus of the subfamily Braconinae which is one of the cyclostome braconid groups. We connected the parasitoids with their hosts where the data about them were available. There are 290 host species in total belonging to 39 families of four insect orders: Diptera, Coleoptera, Hymenoptera and Lepidoptera.

Sublethal concentrations of chemical insecticides may cause changes in some behavioral characteristics of natural enemies such as functional responses. The residual effect of three synthetic insecticides including deltamethrin, fenvalerate and azadirachtin were studied on functional response of Habrobracon hebetor Say to Ephestia kuehniella Zeller larvae. Seven host densities (2, 4, 8, 16, 32, 64 and 96) were used during a 24 h period. The resulting data were appropriately fit to Type II functional response models in all treatments: (1) control (0.0916 h; and T = 0.2011 h); (2) deltamethrin ( a = 0.0839 h; and T = 0.3560 h); (3) fenvalerate ( a = 0.0808 h and T = 0.3623 h); and (4) azadirachtin ( a = 0.0900 h and T = 0.2042 h). Maximum theoretical parasitism rate ( T/ T ) was 119.34 estimated for control wasps. There was no significant difference between the values of attack rates ( a and a + D ) in all treatments while the handling time was statistically affected in female wasps treated with fenvalerate. Our findings will be useful in safe application of these insecticides in pest management programmes. [ABSTRACT FROM AUTHOR]

Bracon hebetor (Hymenoptera: Braconidae) is a generalist idiobiont ecto-parasitoid that parasitizes a wide range of Lepidoptera and even some phylogenically distant weevil species (Coleoptera; Curculionidae). In the present context, our aim is to find the most suitable host for efficient laboratory rearing of B. hebetor. We compared fitness traits of this parasitoid wasp on five host species, four species belonging to the Lepidoptera, viz. Galleria mellonella (Pyralidae), Helicoverpa armigera and Spodoptera litura (Noctuidae), Sitotroga cerealella (Gelechiidae), and one to the Coleoptera, the alfalfa weevil Hypera postica (Curculionidae). We determined the parasitic potential, paralysis, daily oviposition rate, development time, total adult progeny, sex ratio and survival. Fecundity was followed during five consecutive days and oviposition period was determined, all under laboratory conditions. The best results were obtained on the wax moth larvae (G. mellonella) forwhich B. hebetor proved the highest biological activity in term of paralysis, parasitism and oviposition as compared to other tested host species. In Galleria mellonella, total eggs laid per female per five days and egg-adult survivorship were higher and sex ratio was highly biased toward females, as compared to Hypera postica. Intermediate biological activities were found on Helicoverpa armigera, Spodoptera litura and Sitotroga cerealella. These contrasting results show that the plasticity of this species could also represent an important fitness cost difference in performance, which is discussed in terms of phylogenetic distance of the host species (particularly Pyralidae). In conclusion, the possible application of these results can be used in the economically important field of biological control and improve storage of products affected by insect pests. [ABSTRACT FROM AUTHOR]

Augmentative releases of native natural enemies are viable strategies for suppression of crop pests. Successful implementation of this approach requires in-depth knowledge of the natural enemy, its host(s), and the agroecosystem. In particular, appropriate mass rearing and release strategies rely on a thorough understanding of the reproductive biology of the natural enemy. In the present study, we evaluated the effects of parasitoid source (host habitat origin), fruit condition (i.e., ease of host access for parasitoid), impact of using an alternative host for rearing, and winter-simulated cold storage of hosts on the reproductive performance of Bracon hebetor . Several life history parameters, including attack behavior, proportion of paralyzed hosts, parasitism, oviposition, offspring sex ratio, and life table parameters were measured. Wasps originating from a pomegranate orchard- Ectomyelois ceratoniae host habitat generally had greater reproductive performance than those sourced from stored dry fruit- Plodia interpunctella or tomato field- Helicoverpa armigera habitats. Hosts infesting intact pomegranate fruit suffered greater levels of attack (e.g., paralysis, parasitism, and oviposition) than did more accessible hosts infesting damaged fruit. However, offspring sex ratio was generally more female-biased in the damaged fruit treatments. The developmental period of B. hebetor larvae and pupae was shorter (mean generation time) on Ephestia kuehniella hosts that had been subjected to a 2-month cold storage period (winter simulation) than untreated control hosts not subjected to cold storage. Sex ratio of offspring did not differ significantly between the treatments. Our studies demonstrated differential effects of wasp population source, and other biotic factors, on the reproductive biology of B. hebetor . Our current understanding suggests that efficacious protection of pomegranate crops with B. hebetor might be accomplished by using a rearing protocol that incorporates parasitoids originating from a pomegranate- E. ceratoniae source, followed by rearing on cold-treated E. kuehniella prior to release. Development of optimal release strategies is a topic for future studies. [ABSTRACT FROM AUTHOR]

The wheat stem sawfly (Cephus cinctus Norton) is a major historical pest of wheat in the northern Great Plains of North America. The insect spends most of its life as a larva protected inside grass stems so that its management has relied on strategies other than insecticides. We conducted a study in southern Alberta from 2006-2009 to assess the effects of wheat species, cultivar, seeding rate, and blending a resistant and a vulnerable cultivar, on oviposition, larval infestation, and cutting damage. The mortality caused by its primary parasitoid, Bracon cephi (Gahan), was also assessed to investigate the potential benefit of cultivar blends to enhance sawfly biological control. Sawfly laid fewer eggs on plants of the durum cultivar 'AC Avonlea' and on those of the solid-stemmed cultivar 'Lillian' compared to plants of the hollow-stemmed cultivar 'CDC Go.' Larval establishments (infestation) followed a similar pattern to that of oviposition. At these locations there was low cutting damage in most years and to a large extent this was due to mortality inflicted by the parasitoid Bracon cephi (40-60%). However, the remaining mortality was attributed to other factors and host, particularly the inclusion of the solid-stemmed cultivar. Direct and indirect factors likely affected the success of the parasitoid in the crop monocultures and blends, and these mechanisms require further research. [ABSTRACT FROM AUTHOR]

Bracon hebetorSay shows high fecundity and natural rate of increase which makes it a promising enemy againstCorcyra cephalonica,a very common stored grain pest. The functional response of the parasitoid can determine potential of a species to act as a biocontrol agent; it defines parasitoid’s searching efficiency and provides an understanding of host–parasitoid interaction. The mean longevity of female parasitoids had no significant difference when maintained at different densities of host insects. However, progeny sex ratio was significantly affected when different host densities were maintained during its adult life. The net fecundity rate (R0) and total fecundity rate (Rt) were highest when host density was five hosts per reproductive chamber. The mean length of generation time (T.c.) was higher on host density one compared to other densities. The intrinsic rate of increase (rm) was highest when the host density was five and lowest on 20 hosts per reproductive chamber. Other life table parameters were also affected significantly. On the basis of life table statistics, we can say that this type of density-responsive behaviour can be considered to be the most stabilizing one. [ABSTRACT FROM AUTHOR]

The ectoparasitoid wasp,Habrobracon hebetorSay (Hymenoptera: Braconidae) is a valuable biocontrol agent attacking larval stages of many lepidopteran pests includingHelicoverpa armigera(Hübner) (Lepidoptera: Noctuidae). The possibility of combined application of this parasitoid wasp with other biological control agents and chemical insecticides is necessary for the success of an Integrated Pest Management (IPM) programme. One of the most important behaviours of a parasitoid refers to the number of hosts attacked by per parasitoid as a function of host density. In this research, the single and joint effects of the insecticide, Proteus® and the entomopathogenic fungus,Metarhizium anisopliaesensu lato (Metsch.) Sorokin (Hypocreales: Clavicipitaceae) (isolate M14) were studied on the functional response ofH. hebetor. Newly mated females (<24 h) from treated pupae ofH. hebetorwere used to study the functional response of this parasitoid wasp to different densities ofH. armigeralarvae. A type II functional response was observed in all treatments. The results revealed that control and Proteus® treatments developed the lowest (0.5599 ± 0.0373 h) and the highest (0.5709 ± 0.0443 h) handling time, respectively. The most and the least values of attack rate were observed in control (0.0996 ± 0.0164 h−1) and Proteus® (0.0776 ± 0.0119 h−1) treatments, respectively. The maximum theoretical parasitism rate (T/Th) was estimated to be 42.86 for female control wasps. After conducting field experiments on functional response along with life table parameters,M. anisopliaesensu lato (isolate M14) may be used as a compatible biocontrol agent withH. hebetorin IPM programmes ofH. armigera. [ABSTRACT FROM PUBLISHER]