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Climate change raises a serious threat to global entomofauna—the foundation of many ecosystems—by threatening species preservation and the ecosystem services they provide. Already, changes in climate—warming—are causing (i) sharp phenological mismatches among host–parasitoid systems by reducing the window of host susceptibility, leading to early emergence of either the host or its associated parasitoid and affecting mismatched species' fitness and abundance; (ii) shifting arthropods' expansion range towards higher altitudes, and therefore migratory pest infestations are more likely; and (iii) reducing biological control effectiveness by natural enemies, leading to potential pest outbreaks. Here, we provided an overview of the warming consequences on biodiversity and functionality of agroecosystems, highlighting the vital role that phenology plays in ecology. Also, we discussed how phenological mismatches would affect biological control efficacy, since an accurate description of stage differentiation (metamorphosis) of a pest and its associated natural enemy is crucial in order to know the exact time of the host susceptibility/suitability or stage when the parasitoids are able to optimize their parasitization or performance. Campaigns regarding landscape structure/heterogeneity, reduction of pesticides, and modelling approaches are urgently needed in order to safeguard populations of natural enemies in a future warmer world. [ABSTRACT FROM AUTHOR]

Red imported fire ants mounds have been suggested as a potential reservoir for beneficial entomopathogenic fungal species that are vital for more complex roles in the ecosystem aside from infecting the insects. In the current study, the assemblage of fungal symbionts of the red imported fire ants (RIFA) were obtained across five cities in Guangdong Province, China. The sampling areas were selected because of high occurrence of fire ants mounds in the regions. Mound soils, plant debris within mounds, and ants were collected from three sampling locations in each city for potential isolation of entomopathogenic fungal associates of RIFA. All samples were collected during the spring of 2021. Following successful isolation from substrates, the patterns of fungal species composition, and richness were evaluated. In total, 843 isolates were recovered, and based on their phenotypic distinctiveness and molecular characterization based on DNA sequences of multiple loci including the ITS, SSU, and LSU regions, 46 fungal taxa were obtained, including 12 that were unidentified. Species richness and abundance was highest in the mound soils, while the lowest value was recorded from the ant body. As per the different locations, the highest abundance level was recorded in Zhuhai, where 15 fungal taxa were cultivated. The most common taxa across all substrates and locations was Talaromyces diversus. A baseline analysis of the fungal community composition of RIFA would better our understanding on the interactions between these social ants and their associated microbial organisms, and this knowledge in turn would be important for the successful management of the RIFA. [ABSTRACT FROM AUTHOR]

In response to mitigating the negative impacts of synthetic insecticides in controlling Diaphorina citri, the main vector of Huanglongbing, we assessed the effects of endophytically colonized Citrus limon seedlings by Beauveria bassiana BB‐16 on the population fitness of D. citri using the age‐stage two‐sex life‐table theory. The mean fecundity (F) and reproductive rate (R0) of the F1 generation of D. citri reared on endophytically colonized plants (F = 121.7; R0 = 30.43) were significantly lower than the endophyte‐free plants (F = 438; R0 = 197.1). In addition, the values of finite rate of increase (λ) and intrinsic rate of increase (r) on endophytically colonized plants (λ = 1.0927 day−1; r = 0.0887 day−1), were significantly lower than the endophytes free plants (λ = 1.1528 day−1; r = 0.1422 day−1). Moreover, the pre‐adult survival rate (sa) on endophytically colonized plants (sa = 37.5%) was significantly lower than the endophyte‐free plants (sa = 75%). Our results demonstrate that B. bassiana BB‐16 established as endophyte in C. limon under controlled conditions, reduced the population fitness of D. citri progeny and highlight the potential of integrating this entomopathogenic fungus as endophyte for sustainable management of D. citri and other citrus pests in citrus orchards. [ABSTRACT FROM AUTHOR]

Summary: Microbiome analysis in a host–parasitoid interaction network was conducted to compare the taxonomic composition of bacterial communities of Diaphornia citri, Tamarixia radiata, and Diaphorencyrtus aligarhensis. The comparative analysis revealed differences in the composition and diversity of the symbiont populations across the host and its associated parasitoids. Proteobacteria was the most dominant phylum, representing 67.80% of the total bacterial community, while Candidatus Profftella armature and Wolbachia were the dominant genera across the host and parasitoids. There were clear differences observed in alpha and beta diversity of microbiota through the host and its associated parasitoids. The function prediction of bacterial communities and Pearson correlation analysis showed that specific bacterial communities displayed positive correlations with the carbohydrate metabolism pathway. Furthermore, when symbiotic bacteria were eliminated using a broad‐spectrum antibiotic, tetracycline hydrochloride, the parasitoids' median survival time and longevity were significantly reduced. We confirmed the physiological effects of symbiotic bacteria on the fitness of parasitoids and demonstrated the effect of antibiotics in decreasing the food intake and measurement of amino acids in the hemolymph. This study sheds light on basic information about the mutualism between parasitoids and bacteria, which may be a potential source for biocontrol strategies for citrus psyllid, especially D. citri. [ABSTRACT FROM AUTHOR]

The effect of the entomopathogenic fungus Beauveria bassiana (BB-12) on the biological characteristics of Tamarixia radiata parasitizing Diaphorina citri was studied under laboratory conditions. Twenty 3rd–5th instar nymphs were exposed to a single already-mated female parasitoid (1 day old) and removed after 24 h. Subsequently, the nymphs were sprayed at 1, 24 and 48 h post-exposure with 1 × 108 conidial mL−1 suspension. The percentage of parasitism recorded was 22%, 35% and 41% at 1, 24 and 48 h, respectively. The emergence rate varied between 28%, 51% and 49% at 1, 24 and 48 h, respectively. In a subsequent experiment, nymphs of D. citri were sprayed with 1 × 108 conidial mL−1 suspension and then exposed to T. radiata at 1, 24 and 48 h post-spraying to allow for parasitism to occur. The percentage of parasitism recorded was 18%, 27% and 28% at 1, 24 and 48 h, respectively, significantly lower than the parasitism rate recorded in the control (48%). The percentage of emergence varied between 24%, 44% and 45% at 1, 24 and 48 h, respectively. In both experiments, no significant difference was observed in the pre-adult duration (days) and the sex ratio of F1 generation. Meanwhile, significant differences were observed in the longevity of the F1 generation of females and males of T. radiata in a treatment consisting of spraying the fungal suspension and the control. Overall, the findings of the current study revealed a negative interaction between T. radiata and B. bassiana in controlling D. citri nymphs. This outcome is believed to be a result of the antagonistic effects of B. bassiana on the developmental process of the pre-adult stages of the parasitoid. However, our results also show that with a properly timed application (allowing parasitism to occur over an extended period of time before the application of the fungus), T. radiata could potentially be used in combination with B. bassiana for the successful biological control of D. citri. This should be carried out in order to minimize the potentially negative interactions between these two biological agents. [ABSTRACT FROM AUTHOR]

Tamarixia radiata Waterson (Hymenoptera: Eulophidea) is the principal natural enemy used for the control of the major citrus pest Diaphorina citri Kuwayama (Hemiptera: Liviidae). In this study, we collected the life-history data of T. radiata at four different temperatures (20, 27.5, 30, and 35°C) and analyzed them by using the age-stage, two-sex life table. The longest preadult developmental time (16.53 d) was observed at 20°C, whereas the shortest one was 7.29 d at 35°C. The preadult development rate was well-fitted to a linear equation. The lower threshold temperature (T0) was 7.85°C and the thermal summation (K) was 193.36 degree-day. The highest fecundity (F) was 322.7 eggs per female was at 27.5°C, whereas the lowest one was 10.8 eggs per female at 35°C. The net reproductive rate (R0) were 70.97, 169.42, 55.70, and 3.25 offspring at 20, 27.5, 30, and 35°C, respectively; the intrinsic rate of increase (r) were 0.1401, 0.3167, 0.3517, and 0.1143 d-1, respectively. The highest values of fecundity, net reproductive rate, intrinsic rate of increase, and finite rate of increase were observed at 27.5°C. The relationships among F, R0, Nf, and N in all treatments were consistent with R0=F×(Nf/N). The age of peak reproductive value was close to the total preoviposition period in all treatments. Population projections based on the age-stage, two-sex life table showed the dynamics of stage structure and its variability. Faster population growth was observed at 27.5 and 30°C., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)