Efficacy of wax-based bait stations for controlling Bactrocera dorsalis (Diptera: Tephritidae).

BACKGROUND: Bactrocera dorsalis is a notorious pest and spraying of insecticides has been the major approach to controlling its damage. However, insecticide abuse has led to negative impacts on public health and insecticide resistance; hence, sustainable strategies, such as bait stations, need to be developed and taken into account for B. dorsalis management. In this study, we integrated insecticide, sugar, olfactory and visual elements into a wax matrix to formulate a long-lasting bait station. We determined its efficacy against B. dorsalis under field conditions. RESULTS: The optimal bait station was a wax matrix incorporated with 1% spinetoram, 1% yellow pigment, and 3% ammonium acetate, and was spherical in shape with a 6 cm diameter. The longevity of this bait station was at least 10 weeks under field conditions. In a release and recapture experiment performed in Orchard 1, the bait stations were as effective as bait spray in controlling sterile fly populations, and more effective than the control. In a 2-year field trial conducted in Orchard 2, the number of female B. dorsalis and fruit infestation in the area where bait stations had been deployed was similar to the areas treated with cover spray. In Orchard 3, deployment of bait stations combined with chemical cover spray treatment decreased the population of female B. dorsalis and fruit damage more effectively than cover spray alone. CONCLUSIONS: Overall, wax-based bait stations can be regarded as a viable alternative to insecticides or a synergistic method for managing B. dorsalis. © 2022 Society of Chemical Industry.

A new species of Diachasmimorpha Viereck (Hymenoptera: Braconidae: Opiinae) from China.

Diachasmimorpha anshunensis sp. nov., a koinobiont endoparasitoid of larvae of Zeugodacus tau (Walker) (Tephritidae: Diptera), is discovered from Guizhou (Southwest China) and is described by multiple forms of evidence. Morphological characteristics, photographs, and molecular data differentiating it from similar species are provided. Several biological characteristics of this new parasitoid, observed in a laboratory setting, are also provided as evidence to separate it from the most similar species in appearance.

Quantification and Impact of Cold Storage and Heat Exposure on Mass Rearing Program of Bactrocera dorsalis (Diptera:Tephritidae) Genetic Sexing Strain.

Cold storage and heat exposure are crucial components of tephritid fruit fly mass-rearing programs, as they influence the development and fitness traits of produced flies. This work investigated the effects of cold storage on the pupal developmental parameters and quality of Bactrocera dorsalis (Hendel) genetic sexing strain (GSS) adults. Furthermore, the impact of short-term thermal exposure on the fecundity of B. dorsalis (GSS) that also underwent pupal cold storage was examined. Our results show that pupal development time, emergence rate, partial emergence rate, flight ability and fecundity were significantly affected by low temperature and pupal age and their interaction. Pupal cold storage did not pose negative impacts on the mating competition and response to methyl eugenol (ME) in the males. In addition, compared with the adults that were subjected to the same pupal storage protocol (five-day-old pupae stored at 13 °C), adult exposure to 41 °C for 1 h showed significant reparative effects on fecundity. In summary, the cold storage procedure of B. dorsalis (GSS) pupae has the potential to improve the flexibility and efficiency of mass-rearing schedules. Furthermore, short-term thermal exposure showed reparative effects on the fecundity costs induced by pupal cold storage in B. dorsalis (GSS).

Life History and Host Preference of Trichopria drosophilae from Southern China, One of the Effective Pupal Parasitoids on the Drosophila Species.

This study aims to evaluate several life-history traits of a T. drosophilae population from southern China and its parasitic preference of three Drosophila species. For mated T. drosophilae females, the mean oviposition and parasitization period were 27.20 and 37.80 d, respectively. The daily mean parasitization rate was 59.24% per female and the lifetime number of emerged progeny was 134.30 per female. Trichopria drosophilae females survived 37.90 and 71.61 d under host-provided and host-deprived conditions, respectively. To assess the potential for unmated reproduction in T. drosophilae, the mean oviposition and parasitization period of unmated females was 22.90 and 47.70 d, respectively. They had a daily mean parasitization rate of 64.68%, produced a total of 114.80 offspring over their lifetime, and survived 52 d. Moreover, T. drosophilae showed a preference towards D. suzukii based on the total number of emerged offspring under a choice test. Our findings indicate that T. drosophilae from southern China appears to be suitable for the control of D. suzukii in invaded areas, due to its reproductive potential.