Endosymbiosis allows to persist in dry conditions.

Insects frequently associate with intracellular microbial symbionts (endosymbionts) that enhance their ability to cope with challenging environmental conditions. Endosymbioses with cuticle-enhancing microbes have been reported in several beetle families. However, the ecological relevance of these associations has seldom been demonstrated, particularly in the context of dry environments where high cuticle quality can reduce water loss.

Nutritional symbionts enhance structural defence against predation and fungal infection in a grain pest beetle.

Many insects benefit from bacterial symbionts that provide essential nutrients and thereby extend the hosts' adaptive potential and their ability to cope with challenging environments. However, the implications of nutritional symbioses for the hosts' defence against natural enemies remain largely unstudied. Here, we investigated whether the cuticle-enhancing nutritional symbiosis of the saw-toothed grain beetle Oryzaephilus surinamensis confers protection against predation and fungal infection.

Metabolic Cost of a Nutritional Symbiont Manifests in Delayed Reproduction in a Grain Pest Beetle.

Animals engage in a plethora of mutualistic interactions with microorganisms that can confer various benefits to their host but can also incur context-dependent costs. The sawtoothed grain beetle harbors nutritional, intracellular Bacteroidetes bacteria that supplement precursors for the cuticle synthesis and thereby enhance desiccation resistance of its host. Experimental elimination of the symbiont impairs cuticle formation and reduces fitness under desiccation stress but does not disrupt the host's life cycle.

Biochar alleviates the toxicity of imidacloprid and silver nanoparticles (AgNPs) to Enchytraeus albidus (Oligochaeta).

The present study investigated the use of biochar for the alleviation of the toxic effects of a nanosilver colloidal dispersion and a chloronicotinyl insecticide. The survival and reproduction of the potworm Enchytraeus albidus were assessed after exposure to imidacloprid and silver nanoparticles (AgNPs). E.