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Simple Summary: Natural predators such as the chrysopid Chrysoperla lucasina occur in agroecosystems, where they naturally contribute to containing pest populations. Their biological properties can be leveraged by mass rearing in the laboratory and releasing them in the field, where they can express their predatory potential against pest species. To ensure the preservation of these beneficial species, plant protection products should be harmless to them. Accordingly, the use of biopesticides based on microbial entomopathogens, such as the fungus Beauveria bassiana strain ATCC 74040, is promoted as they are generally regarded as safe to non-target species. However, such safety should be demonstrated case by case. In addition, safety should be ensured for both the wild species and those released for biological control. This study involved experiments including laboratory-reared and wild C. lucasina larvae and determined only slight or no effects of B. bassiana on their survival, immature development, adult emergence, and reproductive potential. These findings highlight the compatibility of the predator and this strain of B. bassiana, emphasising the opportunity for their combined use in environmentally friendly pest management strategies. The need to reduce the impact of plant protection products on agroecosystems fosters the use of augmentative biological control involving the release of beneficial species into the field, the employment of entomopathogenic microbials, and the protection of naturally occurring biocontrol agents. This study aimed to investigate the compatibility of the entomopathogenic fungus Beauveria bassiana with the generalist insect predator Chrysoperla lucasina, in comparative experiments involving a laboratory-reared and a wild chrysopid strain. The larvae of the predators were exposed to different concentrations of fungal conidia up to a concentration of 107 conidia/mL by contact and ingestion. The treated insects showed only slight differences in terms of survival and immature development time compared to the untreated control insects. A significant decrease in the proportion of the male adults of C. lucasina that emerged from the laboratory-reared larvae that were exposed to higher concentrations of the fungus suggested a potentially different susceptibility between the sexes. A slightly lower adult emergence rate was observed in the wild strain, while no significant differences were recorded in the adult reproductive performance. These findings indicate that the B. bassiana strain ATCC 74040, at concentrations commonly used in the field, did not pose a significant risk to C. lucasina and can be safely used in combination with this predator for sustainable pest management. [ABSTRACT FROM AUTHOR]

Social insects have evolved colony behavioral, physiological, and organizational adaptations (social immunity) to reduce the risks of parasitization and/or disease transmission. The collection of resin from various plants and its use in the hive as propolis is a clear example of behavioral defense. For Apis mellifera, an increased propolis content in the hive may correspond to variations in the microbial load of the colony and to a downregulation of an individual bee's immune response. However, many aspects of such antimicrobial mechanism still need to be clarified. Assuming that bacterial and fungal infection mechanisms differ from the action of a parasite, we studied the resin collection dynamics in Varroa destructor‐infested honeybee colonies. Comparative experiments involving hives with different mite infestation levels were conducted in order to assess the amount of resin collected and propolis quality within the hive, over a 2‐year period (2014 and 2015). Our study demonstrates that when A. mellifera colonies are under stress because of Varroa infestation, an increase in the number of resin foragers is recorded, even if a general intensification of the foraging activity is not observed. A reduction in the total polyphenolic content in propolis produced in infested versus uninfested hives was also noticed. Considering that different propolis types show varying levels of inhibition against a variety of honey bee pathogens in vitro, it would be very important to study the effects against Varroa of two diverse types of propolis: from Varroa‐free and from Varroa‐infested hives. [ABSTRACT FROM AUTHOR]