Inherited bacteria that parasitically distort the pattern of sex allocation of their host, biasing allocation towards female progeny, are found in many arthropods. One such manipulation is male-killing, where male progeny of infected females die during embryogenesis. We here provide evidence for a male-killing bacterium in the coccinellid beetle, Adonia variegata. We then address 3 questions. First, is this male-killing bacterium one that is found in other hosts, or does it represent a new transition to male-killing within the eubacteria? Using the sequence of the 16S rDNA of the bacterium, we found that the male-killing bacterium is a member of the Flavobacteria--Bacteroides group, most closely related to the male-killing bacterium in another ladybird beetle, Coleomegilla maculata. Secondly, is there any evidence that this bacterium affects female host physiology? In a paired test under nutritional stress, we found no evidence for a physiological benefit to infection, and weak evidence of a physiological cost, in terms of reduced fecundity. Thirdly, is there any evidence of host involvement in the transmission of the bacterium to the germ line? We found no evidence of host involvement. Rather, bacteria migrated to the ovariole independently of host cells. We conclude that the bacterium is a parasite, and discuss how 2 different species of ladybird come to be infected with 1 lineage of bacterium, and why case studies of male-killing bacteria have generally found little evidence of any symbiont contribution to host physiological functioning.
Neonicotinoids, systemic neuro-active pesticides similar to nicotine, are widely used in agriculture and are being investigated for a role in honey bee colony losses. We examined one neonicotinoid pesticide, imidacloprid, for its effects on the foraging behavior of free-flying honey bees (Apis mellifera anatoliaca) visiting artificial blue and white flowers. Imidacloprid doses, ranging from 1/5 to 1/50 of the reported LD50, were fed to bees orally. The study consisted of three experimental parts performed sequentially without interruption. In Part 1, both flower colors contained a 4 μL 1 M sucrose solution reward. Part 2 offered bees 4 μL of 1.5 M sucrose solution in blue flowers and a 4 μL 0.5 M sucrose solution reward in white flowers. In Part 3 we reversed the sugar solution rewards, while keeping the flower color consistent. Each experiment began 30 min after administration of the pesticide. We recorded the percentage of experimental bees that returned to forage after treatment. We also recorded the visitation rate, number of flowers visited, and floral reward choices of the bees that foraged after treatment. The forager return rate declined linearly with increasing imidacloprid dose. The number of foraging trips by returning bees was also affected adversely. However, flower fidelity was not affected by imidacloprid dose. Foragers visited both blue and white flowers extensively in Part 1, and showed greater fidelity for the flower color offering the higher sugar solution reward in Parts 2 and 3. Although larger samples sizes are needed, our study suggests that imidacloprid may not affect the ability to select the higher nectar reward when rewards were reversed. We observed acute, mild effects on foraging by honey bees, so mild that storage of imidacloprid tainted-honey is very plausible and likely to be found in honey bee colonies.
Overwintered pupae of fall webworm, Hyphantria cunea (Drury), were collected from 38 hazelnut (Corylus avellana L. (Betulaceae)) plantations in Samsun province, Turkey, in 2008 and 2009. Four chalcidoid (Hymenoptera: Chalcidoidea) species were reared: Chouioia cunea Yang (Eulophidae), Conomorium amplum (Walker), Dibrachys boarmiae (Walker), and Psychophagus omnivorus (Walker) (Pteromalidae). Overall parasitism was 11.97% and 4.84% for 2008 and 2009, respectively; species richness on sites ranged from one to three species. Psychophagus omnivorus parasitised 6.7% of all pupae and comprised 79% of chalcidoid rearings. Chouioia cunea had the highest clutch average (117) and female:male ratio (44.5:1). Records of Chouioia cunea and Conomorium amplum are new for Turkey and, except for P. omnivorus, all parasitoids are new records for H. cunea in Turkey.
Greenhouses in Turkey under integrated pest management can be colonized by a high number predatory flies of the species Coenosia attenuata Stein, 1903 (Muscidae: Coenosia Meigen, 1826. Studies have shown that Coenosia predators do not simply colonize greenhouses from the outside for short periods but instead they are able to complete their developmental cycle in the greenhouse soil and can become established there for a long period of time. C. attenuata is indigenous to the Palaeotropical region. Its prey spectrum includes whiteflies, black fungus gnats and leaf-mining flies. Studies of the natural occurrence of these predaceous flies in greenhouses led to a recognition of the significance of this complex of beneficials for the control of important greenhouse pests. They can build up effective populations under greenhouse conditions, and as non-specific predators can feed on a variety of pest groups and on innocuous species.
The spotted wing drosophila fly, Drosophila suzukii (Matsumura, 1931) (Diptera: Drosophilidae), is a pest which caused serious crop losses to soft-skinned fruits such as cherries, strawberries, and grapes. In this study, population dynamics of D. suzukii and its associated parasitoids were investigated. The surveys were conducted at one location of Uşak province, Turkey, between April and December of 2017 and 2018. For this purpose, the baited traps were weekly hung on the fruit trees. Population of D. suzukii in 2017 and 2018 peaked at the end of October and in mid-November, respectively. Moreover, three parasitoid species, namely, Leptopilina heterotoma (Thomson, 1862), Ganaspis xanthopoda (Ashmead, 1896) (Hymenoptera: Figitidae), and Pachycrepoideus vindemiae (Rondani, 1875) (Hymenoptera: Pteromalidae), were identified associated with the pest. Among these, G. xanthopoda and L. heterotoma are new records for Turkey Eucoilinae fauna. P. vindemiae was the most abundant parasitoid in both years, while G. xanthopoda was detected only in 2017. This study is the first research to detect parasitoids of D. suzukii in Turkey.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.