Braconid Parasitoid Species Research Articles

Tanggap Parasitoid Braconidae (Hymenoptera) Terhadap Hama Invasif Liriomyza trifolii (Burgess) (Diptera: Agromyzidae) pada Tanaman Sayuran dan Hias di Bali

Response of Braconid Parasitoid Against Invasive Pest, Liriomyza trifolii (Burgess) (Diptera: Agromyzidae) on Vegetable and Ornamental Crops in Bali. Research on the respopnse of Braconid parasitoids to the invasive pest, Liriomyza trifolii that attacks ornamental plants and vegetables in Bali, was carried out from September 2020 to March 2021. This study aimed to determine the type and abundance of parasitoid populations that responded to Liriomyza trifolii on host plants in the field. In addition, this study also aims to evaluate the level of parasitization of each parasitoid against L. trifolii. This study used a purposive sampling method by taking leaf samples that showed active symptoms of Liriomyza larvae in the leaves of plants. The research focused on vegetables and ornamental plants cultivated in lowlands <500 meters above sea level (masl), mediumlands 500-1000 meters above sea level and highlands> 1000 meters above sea level. The results showed that there were two species of Braconid parasitoids that responded to Liriomyza trifolii in the field, namely Opius dissitus and Opius cromatomiyae. The relative abundance and degree of parasitization of the two parasitoids showed variation between host plant species and altitude. The relative abundance of O. dissituse was high in chrysanthemum (10.81%) at an altitude of >1000 masl and low in long beans (0.53%) at an altitude of <500 masl. The highest relative abundance of O. cromatomiyae was in marigold flowers (51.18%) at an altitude of <500 masl and the lowest was in chrysanthemum (44.83%) at an altitude of > 1000 masl. The highest level of parasitization of O. dissitus was found in pakcoy plants (50.00%) at an altitude of >1000 masl and the lowest was in mustard plants (6.06%) at an altitude of <500 masl. The highest level of parasitization of O. cromatomiyae was in celery (33.33%) at an altitude <500 masl and the lowest was in tomato plants (25.00%) at an altitude> 1000 masl. Both species of Braconid parasitoids have high potential as biological control agents for L. trifolii as indicated by their relative abundance and high levels of parasitization against these invasive pests.

Diversity of Braconid Parasitoids (Hymenoptera: Braconide) of Horticultural Insect Pests from Kolhapur, Maharashtra

Braconids (Hymenoptera: Braconidae) are the potential biocontrol agents of insect pests attacking economically important crop plants. Braconids are exclusively parasitic and are reported mainly on lepidopterous pests. These flies parasitize egg, larval, and pupal stage of the insect pests. Horticultural crops are attacked by lepidopterous pests causing severe damage to crops and there by minimizes crop yield. The use of braconid parasitoids as pest control agents helps to reduce the pest population. The braconids are rearable in laboratories and reared parasitoids can be used in pest control programs. The correct identification, host preference and parasitic potential of the parasitoids plays important role in their utilization in pest control programs. The species reported belongs to genus Cotesia, Apanteles, Bracon, Glyptapenteles, Chilonus, Dolichogenidea, Agathis, Meteorus etc. and have been found parasitizing the insect pests of different horticultural plants. Total 35 species of braconid parasitoids were reported from the Kolhapur district, Maharashtra. The studies will help to add knowledge on number of braconid species found in study area and also explore them to use in biocontrol programs in the region.

The impact of climate on the winter strategies of insects

The impact of climate on the winter strategies of insects

Rapid Responses of Winter Aphid-Parasitoid Communities to Climate Warming

Consequences of environmental fluctuations, including those associated with climate changes, can have a knock-on effect from individual to community scale. In particular, changes in species seasonal phenology can modify the structure and composition of communities, with potential consequences on their functioning and the provision of ecosystem services. In mild climate areas, aphids can be present in cereal fields throughout the winter, which allows aphid parasitoids to remain active. Using a nine-year dataset of aphid-parasitoid winter trophic webs in cereal fields of Western France, we report that the community structure and composition that prevailed before 2011 have recently shifted toward a more diversified community, with the presence of two new braconid parasitoid species (Aphidius ervi and Aphidius avenae), a few hyperparasitoid species and one aphid species (Metopolophium dirhodum). Increases in minimal winter temperatures and the frequency of frost events across the years partially explain observed community changes. Strong bottom-up effects from the relative abundances of aphid species also determine the relative abundance of parasitoid species each winter. Strong compartmentalization in parasitoid preference for host is reported. We suggest the recent modifications in parasitoid community composition to be linked to shifts in diapause expression (reduction or arrest of the use of winter diapause) and to host availability throughout the year. We highlight the implications for natural biological control in cereal fields. Perspectives are proposed to predict the composition of future host-parasitoid communities in the climate change context.

Host acceptance by three native braconid parasitoid species attacking larvae of the Mexican fruit fly, Anastrepha ludens (Diptera, Tephritidae)

We studied the oviposition and host acceptance behavior of three braconid parasitoid species native to Mexico, Doryctobraconcrawfordi (Viereck), Opiushirtus (Fischer), and Utetesanastrephae (Viereck), with potential to be considered as biocontrol agents against tephritid fruit fly pests in the Neotropics. Third instar larvae of Anastrephaludens (Loew), with and without previous parasitization by conspecifics, were simultaneously offered to females of each species, and the individual behavior was video recorded to construct oviposition flow diagrams. The patterns of foraging and host acceptance were similar in the studied species; all rejected mostly parasitized hosts suggesting that this strategy is common in the guild of larval parasitoids attacking Anastrepha spp. The complete searching and host acceptance process took 2.2 ± 0.1 min (mean ± SE) in D.crawfordi, 1.7 ± 0.1 s in U.anastrephae and 1.5 ± 0.1 s in O.hirtus. Notably, because of toxins injected by parasitoid females during oviposition, the parasitized hosts experienced a transient paralysis of variable duration. Hosts attacked by U.anastrephae remained immobile for the shortest time (12.5 ± 1 min) (mean±SE), followed by D.crawfordi (20.5 ± 3.4 min) and O.hirtus (24.1 ± 2 min). Our data revealed a notable discrimination ability in all three species, and that behavioral differences lay mainly in the time of parasitization and in the duration of paralysis experienced by attacked hosts. This suggest that the three species could be valuable as biocontrol agents, but additional studies are necessary to better understand the advantages and limitations of each one as natural enemies of fruit fly pests.

The response of four braconid parasitoid species to methyl eugenol: Optimization of a biocontrol tactic to suppress Bactrocera dorsalis

Methyl eugenol (ME) is the most common tephritid male lure used in studies investigating Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), a highly destructive pest species. The following four species of braconid wasps (Hymenoptera: Braconidae) are parasites of several Tephritidae flies of economic significance: Fopius arisanus (Sonan), F. vandenboschi (Fullaway), Diachasmimorpha longicaudata (Ashmead) and Psyttalia incisi (Silvestri). An integrated pest management (IPM) strategy involving the release of multiple parasitoid species, the release of sterile males, and the placement of ME-lure traps was recently implemented in southern China. This study evaluated the effects of ME on braconid parasitoids. Based on the results from olfactometer bioassays, all parasitoid species were significantly repelled by undiluted ME. Furthermore, attractant-influenced behavioral activities occurred at relatively low concentrations of ME (e.g., 0.01, 0.1, and 1 μl/ml), whereas the effects of the repellent increased to significant levels as the concentration increased. There were no significant differences in electroantennogram (EAG) responses among different doses of ME, but the number of F. arisanus parasitoids attracted to traps containing host eggs decreased significantly at higher concentrations, e.g., 10, 100 and 1000 μl/ml. In addition, the number of F. arisanus females that were attracted to the host egg trap decreased significantly with higher concentrations of ME (10, 100 and 1 μl/ml). The number of F. arisanus females that exhibited ovipositional behavior in an environment without ME was significantly higher than those with different concentrations of ME. This study improves our understanding of control tactic interactions as well as the optimization of various processes involved in the IPM program.

Frugivorous Flies (Diptera: Tephritidae, Lonchaeidae) Associated with Fruit Production on Ilha de Santana, Brazilian Amazon

We conducted a survey of the species of frugivorous flies (Tephritidae and Lonchaeidae), their hosts, and their parasitoids found on Ilha de Santana, Amapa State, Brazilian Amazon. We also assessed host plant use by Bactrocera carambolae Drew & Hancock. Fruits were collected from various plant species, at 30 d intervals, from Jan to Jul 2015. In total, 149 fruit samples were collected (3,142 fruits, 76.3 kg), belonging to 20 plant species (9 native and 11 introduced) in 13 botanical families. Infestation by fruit flies was observed in 86 samples (11 species in 8 botanical families). Specimens of 5 species of Tephritidae and 4 species of Lonchaeidae fruit flies were obtained, as well as 3 species of braconid parasitoids. The most important fruit fly species on Ilha de Santana are: B. carambolae, for being a species of quarantine importance; and Anastrepha obliqua (Macquart) and Anastrepha striata Schiner, for infesting plant species of local socioeconomic importance. Averrhoa carambola (Oxalidaceae), Eugenia uniflora (Myrtaceae), Malpighia emarginata (Moc. & Sesse) ex DC. (Malpighiaceae), and Psidium guajava (Myrtaceae) are the host plants responsible for sustaining the population of B. carambolae.

Preliminary inventory of hymenopteran parasitoids associated with fruit-infesting flies (Diptera: Tephritidae) in Northern Ghana

ABSTRACTBaseline studies were conducted to determine the parasitoids associated with fruit flies in the northern savanna ecology of Ghana. Fruit fly puparia obtained from incubation of 17 host fruit species were maintained in rearing cages for the emergence of parasitoid wasps. Four species of braconid parasitoids namely, Fopius caudatus (Szépligeti), Psyttalia cosyrae (Wilkinson), Psyttalia concolor (Szépligeti) and Diachasmimorpha fullawayi (Silvestri) were recovered. F. caudatus was the most abundant parasitoid (61.0%) reared from most host fruits while D. fullawayi was the least abundant (7.7%). The overall mean parasitism rate was 7.1% with the highest record in Annona senegalensis Pers., Sarcocepholus latifolium S. Bruce and Icacina senegalensis Juss. Ceratitis cosyra and Bactrocera invadens were the fruit fly species most commonly reared that produced F. caudatus, and to a lesser extent, P. cosyrae. The peak occurrence of the parasitoids coincided with the peak of the rains and the maturity period of many of the host fruits. This first inventory of tephritid parasitoids in Ghana provides critical baseline data for biological control efforts in the future.

Incorporating variability in point estimates in risk assessment: Bridging the gap between LC50 and population endpoints.

Historically, point estimates such as the median lethal concentration (LC50) have been instrumental in assessing risks associated with toxicants to rare or economically important species. In recent years, growing awareness of the shortcomings of this approach has led to an increased focus on analyses using population endpoints. However, risk assessment of pesticides still relies heavily on large amounts of LC50 data amassed over decades in the laboratory. Despite the fact that these data are generally well replicated, little or no attention has been given to the sometime high levels of variability associated with the generation of point estimates. This is especially important in agroecosystems where arthropod predator-prey interactions are often disrupted by the use of pesticides. Using laboratory derived data of 4 economically important species (2 fruit fly pest species and 2 braconid parasitoid species) and matrix based population models, the authors demonstrate in the present study a method for bridging traditional point estimate risk assessments with population outcomes. The results illustrate that even closely related species can show strikingly divergent responses to the same exposures to pesticides. Furthermore, the authors show that using different values within the 95% confidence intervals of LC50 values can result in very different population outcomes, ranging from quick recovery to extinction for both pest and parasitoid species. The authors discuss the implications of these results and emphasize the need to incorporate variability and uncertainty in point estimates for use in risk assessment.

Aphidophagous parasitoids can forage wheat crops before aphid infestation, Parana State, Brazil.

Aphid parasitoids are common in Brazilian wheat fields, and parasitize aphids at the wheat tillering stage. However, there is little information available about when this natural enemy occurs in wheat crops. This study investigated the initial occurrence of aphid parasitoids in four commercial wheat crops in northern Paraná during the 2009 crop season. We installed two Malaise traps at each wheat farm, and 400 tillers were assessed weekly in each field for aphid abundance. During this study, we captured 4,355 aphid parasitoids and 197 aphids. Three species of braconid parasitoids were identified, including Aphidius colemani (Viereck 1912), Lysiphlebus testaceipes (Cresson 1880), and Diaeretiella rapae (McIntosh 1855). The aphids species identified were Rhopalosiphum padi (Linnaeus 1758) and Sitobion avenae (Fabricius 1775). This study showed that aphid parasitoids are present in wheat crops even when aphid densities are low, and in one farm, occurred before the aphids colonization. These reports can justified the high efficiency of these natural enemies against aphids in wheat fields.

Effect of host diet and adult parasitoid diet on egg load dynamics and egg size of braconid parasitoids attacking Anastrepha ludens

The quantity and quality of host nutrients can affect fitness‐related traits in hymenopteran parasitoids, including oogenesis. The present study tested the prediction that a high host quality will influence oogenesis‐related traits positively in synovigenic parasitoids, and that a high‐quality adult parasitoid diet can positively affect the same parameters, potentially compensating for development on low‐quality hosts. Four braconid parasitoid species with contrasting life histories are reared on a low‐quality diet [Anastrepha ludens Loew (Diptera: Tephritidae) larvae reared on mango] or a high‐quality (artificial) diet. Adult parasitoids are provided with a high‐quality (honey ad libitum), moderate‐quality (honey every other day) or low‐quality (guava pulp) diet. Generalist species that encounter high variation in host quality naturally are predicted to be more flexible in dealing with nutrient shortfalls than specialist species. By contrast to the predictions, low‐quality hosts yield parasitoids with higher egg loads in two species: Opius hirtus Fisher and Diachasmimorpha longicaudata Ashmead. However, as predicted, a high‐quality adult diet exerts a positive effect on egg load (Utetes anastrephae Viereck), egg size (Doryctobracon crawfordi Viereck) and egg maturation rate (D. longicaudata, O. hirtus and U. anastrephae). The generalist D. longicaudata varies in egg load and maturation rate depending on host quality and adult diet, respectively. Evidence of the combined effect of both factors on parasitoid fertility is presented for the specialist O. hirtus. The theoretical and practical implications of these findings are discussed.

Anastrepha species (Diptera: Tephritidae), their hosts and parasitoids in southern Amapá State, Brazil

This work was carried out to record the species of Anastrepha, their host plants and associated parasitoids in Laranjal do Jari and Vitória do Jari, Amapá State. Fleshy fruits of 17 species of 13 families were sampled, from February to July of 2006, in main districts of both municipalities. Nine species of Anastrepha and six species of braconid parasitoids were sampled during this study.

Natural Occurrence of Parasitoids ofAnastrephaspp. Schiner, 1868 (Diptera: Tephritidae) in Different Host Plants, in Itaguai (RJ), Brazil

The relationship amongAnastrephaspp. flies, their parasitoids, and host plants in Itaguai (RJ), Brazil, is described. Samples of mature fruit were taken from 12 different host plant species. Four species of braconid parasitoids and four species of tephritids subsequently emerged from the collections.Anastrepha fraterculus(Wiedemann) was parasitized by all of the braconids, i.e.,Doryctobracon areolatus(Szepligeti),D. brasiliensis(Szepligeti),Utetes (Bracanastrepha) anastrephae(Viereck), andOpius bellusGahan.A. obliqua(Macquart) andA. distinctaGreene were attacked by all the parasitoids, exceptD. brasiliensis. A. sororculaZucchi was parasitized byD. areolatusandU. anastrephae. A. obliquawas the most common fly species.D. areolatusaccounted for 89.23% of the total parasitization. The overall rate of parasitism ofAnastrephaspp. was 10.4%. However, parasitism varied considerably among host plants. Flies fromEugenia uniflora, E. brasiliensis, Spondias purpurea,andPsidium guajavawere the most heavily parasitized at 59.64, 23.27, 17.47, and 16.02%, respectively. Some tropical fruit host plants for theAnastrephaflies markedly facilitate parasitoid multiplication and deserve attention both as reservoirs of natural enemies and as targets for biological control within integrated fruit fly control programs.

Apple, Airblast Evaluation of Insecticides, 1993

Abstract Experimental sprays were applied to 3 tree plots in a randomized block design consisting of 2 replicates of ‘Yorking’ and 2 replicates of ‘Golden Delicious’ with a buffer tree between plots and a buffer row between blocks. These trees were spaced 20 × 30 ft apart and were 19 years old. Experimental sprays were applied with a Friend Airmaster ‘309’ calibrated to deliver 100 gpa at 2.0 mph. Application dates and materials varied between treatments and are listed in the table for WALH. All applications were complete sprays. A routine schedule of fungicides (Dithane 75DF, Nova 40WP, captan 50WP and Benlate 50DF) was maintained throughout the experiment. Effectiveness on SA was evaluated by counting aphid-infested leaves/10 top terminals, and aphids/most infested leaf. The effect of the sprays on WALH was evaluated by counting nymphs/25 injured leaves/tree. Effectiveness of test chemicals on ERM and ZM was evaluated by counting these mites several times during the season on samples of 25 random leaves/tree, 100 leaves/treatment. The effect of sprays on S. punctum was evaluated by 3-min counts of adults and larvae around the periphery of the test trees. STLM were evaluated by a 5-min count of mines around the periphery of the trees at the end of each of the first two generations before peak emergence of adults. OFM shoot injury was assessed by making a 3 min observation around the periphery of each tree and counting injured shoots. Internal feeding lepidoptera were evaluated with a 5-min count of apples exuding frass and the total number of apples evaluated to give percent injured apples. Effectiveness of chemicals on fruit feeders was assessed for injury by scoring drop apples on 6 and 21 Jul and 3 and 16 Aug and picked samples of 50, 100 and 100 fruit per replication on 16 Aug, 3 and 20 Sep, respectively. Pest pressure was extremely high throughout the season. Fruits were rated as 0 (no russet), 1 (raised lenticels), 2 (1-10% russeted surface), 3 (11-25% russeted surface), 4 (26-50% russeted surface), or 5 (>51% russeted surface). Possible ranges are 0-30 (none to raised lenticels) 31-60 (raised lenticels to 1- 10% russeted surface), 61-90 (1-10% to 11-25% russeted surface, 91-120 (11-25% to 26-50% russeted surface), and 121-150 (26-50% to >51% russeted surface). Effects on parasitoids attacking CM and OFM were evaluated several times during the season on a single tree within each plot by picking up to 20 apples exuding frass in a 10-min count and rearing the larvae in the laboratory on a semi-synthetic lima bean diet at 20 °C, 16:8 D:L. Injured apples were collected on 7 and 22 Jun, 7 and 19 Jul, 4 and 18 Aug, and 2 Sept. Larvae of CM and OFM were transferred singly to diet cups on each collection date and monitored several times a week for adult moth and parasitoid emergence for 5 weeks. Two species of braconid parasitoids were found during these evaluations, Macrocentrus delicatus which was by far the most common and Charmon extensor. Rates of parasitism for each treatment were calculated by dividing the total number of parasitoids by the total number of parasitoids plus total number of CM and OFM adults.

Survival, Longevity, and Reproduction of Tephritid Fruit Fly Parasitoids (Hymenoptera: Braconidae) Reared from Fruit Flies Exposed to Azadirachtin

Eclosion, longevity, and reproduction of three braconid parasitoid species that parasitized tephritid fruit flies exposed to azadiracthin were determined. Psytallia incise (Silvestri) and Diachasmimorpha longicaudata (Ashmead) developed in and eclosed from oriental fruit flies, Dacus dorsalis Hendel, exposed to azadirachtin concentrations that completely inhibited adult fly eclosion. Diachasmimorpha tryoni (Cameron) also eclosed from Mediterranean fruit fly, Ceratitis capitata (Wiedemann) exposed to concentrations of azadirachtin that inhibited fly eclosion. Lifespans of parasitoids that emerged from treated flies were not significantly different from controls. Reproduction of P. incisi that developed in flies exposed to azadirachtin concentrations of > 20 ppm was reduced 63-88%. D. longicaudata and D. tryoni reproduction was unaffected. The potential use ofneem-based insecticides in conjunction with biological control programs is discussed.

Studies on polydnavirus transmission

Polydnaviruses are thought to replicate only in the ovaries of certain hymenopteran species. Nevertheless, in the present study, polydnaviral DNA was found to exist in males of the braconid parasitoid species Cotesia melanoscela and in both male and female non-ovarian tissue of an ichneumonid, Hyposoter fugitivus; preliminary results suggest that viral DNA may be present in an unintegrated form, but whether or not it is encapsidated is unknown. Using interstrain genetic crosses, we demonstrated that C. melanoscela males can apparently transmit at least some viral DNA to female progeny. We suggest that polydnavirus DNAs may be present in most if not all tissues of certain parasitoid species, and are probably maintained within parasitoid populations by vertical transmission through the germ line. In parallel experiments, manually injected eggs of the ichneumonid parasitoid ( H. fugitivus) survived and hatched in Malacosoma americanum larvae in the apparent absence of exogenous polydnavirus; female parasitoids reared in this manner nevertheless carried virus in their ovaries. Experiments utilizing different strains of C. melanoscela also suggest that per os transmission of polydnaviruses (to parasitoid larvae) does not occur, despite the fact that inoculum viral DNA can be shown to persist for several days in the tissues of parasitized host larvae.