Hymenoptera Braconidae Research Articles

FIRST REPORT OF STREBLOCERA MACROSCAPUS(RUTHE) (HYMENOPTERA BRACONIDAE EUPHORINAE) IN ITALY

A female ofStrebloceramacroscapus(Ruthe)(Hymenoptera Braconidae Euphorinae) was captured on a yellow sticky trap during a monitoring survey aimed atstudyinginsectbiodiversityinViareggio district (Lucca, Italy). This is the first report ofthis species inItaly.Biological information onS. macroscapusand itsparticular ecological niche are reviewed,and images of the specimenare presented. The importance of urban gardens and their proximity to the surrounding wild areas is also considered.

Selecting potential nontarget species for host range testing of <i>Eadya paropsidis</i>

Classical biological control is proposed for Paropsis charybdis (Coleoptera Chrysomelidae Chrysomelinae) a eucalypt pest established in New Zealand The Australian solitary larval endoparasitoid Eadya paropsidis (Hymenoptera Braconidae) is under investigation A potential nontarget species list was compiled for host range testing There are no endemic species of paropsines in the New Zealand fauna only invasive pest beetles The most closely related endemic beetles to the paropsines are Chrysomelinae in the genera Allocharis Aphilon Caccomolpus Chalcolampra and Cyrtonogetus Little is known about these species New Zealand has also introduced 12 beneficial chrysomelid weed biological control agents which include Chrysomelinae and their sister group the Galerucinae One endemic beetle six beneficial beetles and two pest beetles are listed as the highest priority species for host specificity testing

Hymenoptera Parasitoid, a Suitable Biodiversity Resource for Vineyard Environmental Discrimination

Vineyards host a high number of insect species and represent suitable environments to investigate the relationships among arthropod community and environmental biodiversity. Hymenoptera Braconidae summarize many of the attributes required to a reliable group of bioindicators. Indeed, they represent a complete assemblage of a family taxon and are quite well known from a taxonomical and faunistic point of view, occupying the top of the ecological (trophic) pyramid and occurring in very diverse habitats. Braconidae subfamilies are often linked to a single host order, so directly expressing in some way, a functional role in the environment. Here we compared the abundance and the community composition of braconid subfamilies in three differently managed vineyards for two years (2012 and 2013). In each vineyard, the community structure resulted quite similar (abundance and composition) during the first part, but significantly diverged in the second part of the research period. Non Metric Dimensional Scale and Permanova Analysis well described the population distribution. The abundance of some subfamilies, consistently with their ecology, resulted significantly related to the habitat variables considered, as showed by the Multiple Regression analysis. The adoption of insecticides seems to not influence negatively braconid populations, probably because the surrounding areas are provided with a rich local vegetation of bushes and trees, where natural enemies can find refuge. The abundance of some subfamilies that adopt an endophagous koinobiont strategy against lepidopteran larvae showed differences statistically significant in the vineyard where the mating disruption technique was adopted, in comparison with their abundance in the other two vineyards.

Endoparasitoids of larval Anomis privata (Lepidoptera: Noctuidae), major pest of Hibiscus syriacus (Columniferae: Malvaceae)

AbstractEndoparasitoids of Anomis privata larvae include five species in three families of two orders. In this work, two species of Hymenoptera Braconidae (Cotesia sp., Microplitis sp.), one species of Ichneumonidae (Mesochorus vittator) and two species of Diptera Tachinidae (Exorista (Podotachina) sorbillans, Timavia amoena) were investigated. Of the 261 larvae of A. privata examined, 32 had a parasite, so the rate of parasitism was 12.26%. Parasitism by taxon was the highest, at 10.35% (27 individuals), in Cotesia sp. in Hymenoptera Braconidae. Parasitoids of Braconidae and Ichneumonidae were larval parasitoids. A parasitic insect of Tachinidae was a larva–pupal parasitoid. Solitary parasitoids included Microplitis sp. in Braconidae and E. sorbillans in Tachinidae. Gregarious parasitoids included Cotesia sp. in Braconidae, M. vittator in Ichneumonidae and T. amoena in Tachinidae. There was also a multiparasitoid (T. amoena) and two superparasitoids (Cotesia sp., M. vittator). A larva of A. privata sought feed even after it was parasitized every parasitoid investigated in this study, so five species of parasitoids were all koinobiont.

Nontarget species selection for host range testing of <i>Cotesia urabae</i>

Classical biological control is being attempted for Uraba lugens (Lepidoptera Noctuidae Nolinae) an Australian eucalypt pest established in New Zealand The Australian solitary larval endoparasitoid Cotesia urabae (Hymenoptera Braconidae) is the most promising agent under investigation A nontarget species list was compiled for host range testing The endemic species Celama parvitis is the sole New Zealand representative of the Nolinae and was highest priority The next most closely related subfamily is the Arctiinae of which New Zealand has four endemic species (Metacrias huttoni M erichrysa M strategica and Nyctemera annulata) and one introduced biological control agent (Tyria jacobaeae) The merits of including other more distantly related members of the Noctuidae and unrelated Lepidoptera filling a similar niche are discussed

Notes on parasitoids ofPhyllonorycter joviella Constant (Lepidoptera, Gracillariidae), with description of a new species ofAchrysocharoides Girault (Hymenoptera, Eulophidae)

The parasitoid complex of Phyllonorycter joviella Constant, an upper surface leaf-miner on Quercus ilex L., was investigated in a restricted area in Liguria (Northwest Italy). Five species were reared: Chrysocharis gemma (Walker), Achrysocharoides tavellae sp. n., A. parva (Delucchi), Pnigalio pectinicornis (Linnaeus) (Hymenoptera Eulophidae), and Pholetesor sp. (Hymenoptera Braconidae), respectively. A. tavellae sp. n. is described and illustrated. Biological data concerning A. parva and A. tavellae are given. The previous key of the European Achrysocharoides (Bryan 1980) is modified to include the new species. The systematic position of A. parva is discussed. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Effects of venom/calyx fluid from the endoparasitic wasp Cotesia plutellae on the hemocytes of its host Plutella xylostella in vitro

Crude venom and calyx fluid from Cotesia plutellae (Hymenoptera Braconidae) were assayed for biological activity toward hemocytes of Plutella xylostella (Lepidoptera Plutellidae). Venom from C. plutellae displayed high activity toward the spreading of plasmatocytes of P. xylostella early in the incubation period, and the inhibition was more severe as the concentration of venom increased. However, most inhibited hemocytes spread normally after being incubated for 4 h. No effects were found toward granular cells from the host. Additionally, the venom from C. plutellae had some lethal effects on hemocytes of P. xylostella at high concentrations. In contrast, when incubated with different concentrations of calyx fluid, the spreading of some hemocytes was inhibited, some began to disintegrate, and some were badly damaged with only the nucleus left. After 4 h, the majority of hemocytes died. The same results were observed when hemocytes were incubated in calyx fluid together with venom. These results show that calyx fluid from C. plutellae may play a major role in the suppression of the host immune system, whereas venom from C. plutellae has a limited effect on hemocytes and probably synergizes the effect of calyx fluid or polydnavirus.

The influence of flower morphology and nectar quality on the longevity of a parasitoid biological control agent

Conservation biological control aims to enhance the efficacy of arthropod biological control agents, such as parasitoids, partly by providing them with access to floral nectar. However, the suitability of a flower species for providing nectar to a parasitoid is dependent on the morphologies of the parasitoid and the flower, as well as on the quality of the nectar. The effects of seven flower species on the longevity of Microctonus hyperodae (Hymenoptera Braconidae), a parasitoid of the Argentine stem weevil, Listronotus bonariensis (Coleoptera: Curculionidae), were measured in the laboratory. The flowers were phacelia (Phacelia tanacetifolia), buckwheat (Fagopyrum esculentum), alyssum (Lobularia maritima), coriander (Coriandrum sativum), white clover (Trifolium repens), red clover (Trifolium pratense) and white mustard (Sinapis alba). The results suggested M. hyperodae was unable to reach nectar of red clover, white clover, alyssum and phacelia, but was able to gain access to the nectar of the other three species. However, only buckwheat and coriander increased its longevity. Flower corolla aperture and depth probably determined the parasitoid’s access to nectar. Accessible nectars were analyzed for sugar composition and the effect of the sucrose/(glucose + fructose) ratio on nectar suitability was assessed. The relevance of these results to other hymenopteran parasitoid species is discussed in terms of selecting the most appropriate floral diversity in agricultural extensification programmes.

Measuring parasitoid carbohydrate levels to improve biological control

Lifetime carbohydrate levels were compared in the laboratory between unfed and honeyfed Microctonus hyperodae (Hymenoptera Braconidae) a parasitoid of the Argentine stem weevil Listronotus bonariensis (Coleoptera Curculionidae) High performance liquid chromatography (HPLC) was used to analyse sugars in individual parasitoids and showed that fed and unfed parasitoids can be distinguished by measuring the total sugar levels Furthermore the fructose/total sugar ratio (f/T) of honeyfed M hyperodae was always higher than that of the unfed individuals This method should prove very useful for determining the nutritional status of fieldcollected parasitoids and for evaluating the benefits gained by parasitoids through the provision of floral resources in the field

Resource utilization and sex allocation in response to host size in two ectoparasitoid wasps on subcortical beetles

AbstractPatterns of host resource utilization and sex ratio manipulation in relation to host size were investigated for two solitary ectoparasitoid wasps, Atanycolus initiator and Spathius brevicaudis (Hymenoptera Braconidae). Both species parasitize subcortical beetles on the trunks of Japanese pine trees. A. initiator is on average 8 times larger in body weight and has an ovipositor that is 3.7 times longer than that of S. brevicaudis. In both parasitoids, the size of emerging wasps was positively correlated with host size, but the host/wasp size regressions were linear for all three major host species in A. initiator, whereas in S. brevicaudis the regression was logarithmic for a relatively large host species. The sex ratios (proportion of males) of both parasitoids emerging from different host species decreased with increasing host size, but the overall sex ratio on each host species was male‐biased in A. initiator, while female‐biased in S. brevicaudis. How the proportion of host consumed changed in response to host size, differed between the two parasitoids for the same host species. In the field survey, the size and sex ratio of the emerging two parasitoids from a dead tree were closely related to host size. However, the spatial distribution of the two parasitoids depended on the bark thickness of the trunk. The data suggest that differences in the relative evaluation of host size and in ovipositor length may enable the coexistence of the two parasitoid wasps.