This study investigated the effects of various titanium nanoparticles (TiO₂NPs) on the structure, function, and trophic levels of the wheat rhizobiome. In contrast to the typically toxic effects of small nanoparticles (~10 nm), this research focused on molecular TiO₂ and larger nanoparticles, as follows: medium-sized (68 nm, NPs1) and large (>100 nm, NPs2). The results demonstrated significant yet diverse impacts of different TiO₂ forms on the rhizosphere microbiota. Large TiO₂NPs2 and molecular TiO₂ adversely affected the bacteriobiome and mycobiome, leading to an increase in autotrophic microbial groups. In contrast, medium-sized TiO₂NPs1 shifted the microbiome toward chemoheterotrophy, promoting plant growth-associated bacteria, fungal saprotrophs, and potential phytopathogens, suggesting a beneficial r-strategy within the rhizosphere. Other treatments induced oligotrophic conditions, resulting in a less flexible rhizobiome with diminished root associations but an increased abundance of Trichoderma spp. Structural modelling revealed that even minor changes in operational taxonomic units (OTUs) could significantly alter the microbiota’s metabolic potential. These findings highlight the importance of further research to optimize nanoparticle applications for sustainable agriculture.

Rice weevil (Sitophilus oryzae) and the lesser grain borer (Rhyzopertha dominica) are very important warehouse pests and, therefore, their control is crucial. At a key moment in the life of adult Sitophilus spp., the obligatory symbiotic nature of the Sodalis pierantonius bacterium opens up a new perspective for natural antibiotics and bactericides. In this study, we used nanopore sequencing for 16S rRNA barcoding to evaluate the internal bacteriome of S. oryzae and R. dominica and sterilized the insects’ internal microbiome with gentamicin. The treatment of the interior of S. oryzae with gentamicin (30 mg·g⁻¹) hampered insect functioning (supposed lack of DOPA (4-dihydroxyphenylalanine) synthesis, stabilizing the exoskeleton by Sodalis pierantonius symbiont) and elicited a lethal effect in the first stages of this pest’s adult life. In addition, we identified biochemical biomarkers (enzymatic activity and substrate utilization) active in living individuals, but inactive in dead individuals (e.g., C8 esterase/lipase and α-chymotrypsin).

Insect frass and vermicompost hold potential applications as fertilizers, with their abilities to improve plant resilience against unfavorable environmental conditions and increase their resistance to pests and diseases. In this study, we explored the effects of vermicompost fertilization, mealworm frass, and superworm frass as potential plant fertilizers for red beet cultivation. We analyzed the connections among chemical parameters, rhizobiome structure and function, and the biometrics of fertilizer-treated plants. In general, soils enriched with vermicompost and superworm frass exhibited the highest macroelement contents. Dry superworm frass fertilization was characterized by the increased availabilities of total nitrogen, NH₄-N, and NO₃-N. The use of vermicompost and mealworm frass resulted in significantly higher red beet biomass values. The presence of the highest N-fixation potential and key hormonal substances involved in plant development, such as auxins and gibberellins, was demonstrated using wet superworm frass. The results indicated that wet superworm frass, similar to vermicompost and dry superworm frass, exhibits high chemoheterotrophic potential. This suggests an r-type strategy and high adaptive flexibility of rhizobial bacteria. As a consequence, both life in the root zone and the microbiome itself may be better adapted to sudden, unfavorable environmental changes or attacks by plant pathogens.

Due to global warming, the rice weevil is an increasing threat. Various species of weevils coexist with endosymbiotic Sodalis pierantonius . This study aimed to check whether different chemical properties of different cultivars of common wheat and barley grain cause disturbances in insect...

The lesser grain borer (Rhyzopertha dominica F.) and the rice weevil (Sitophilus oryzae L.) are stored grain pests that cause significant economic losses in grain storage. This study aimed to analyze the impact of the chemical composition of wheat and barley grain (e.g., protein, fatty acids and total antioxidant capacity) on the development of two species of storage pests and to determine the relationship between the analyzed variables. The study involved the evaluation of 10 wheat cultivars and 10 barley cultivars under laboratory conditions. The observations included assessing the beetles’ progeny abundance, dust mass produced after feeding, and grain mass loss. The chemical composition of the tested wheat and barley cultivars was also determined, and the influence of different chemical compositions on insect development was investigated. The results of the experiment revealed diversity of resistance among cultivars to pest feeding. Larger populations of the lesser grain borer were observed on barley grains, while rice weevil populations were higher on wheat. Cultivars with higher protein and fat content were more susceptible to pest attacks. A connection between the amount of dust, grain mass loss, and the type of pest was also identified, indicating differences in feeding mechanisms and selective food preferences of these insects. The grain chemistry of wheat cultivars, including the content of fatty acids and antioxidants, significantly influenced the progeny abundance of S. oryzae, suggesting the potential of these components as natural barriers against storage pests. This study provides valuable insights for developing breeding strategies to enhance the natural resistance of new grain cultivars to these pests, contributing to the reduction of pesticide use. Statistical analyses confirmed the significance of differences in grain composition in varied resistance to the studied pests. The conclusions drawn from this work may help establish new storage and breeding practices, promoting sustainable agriculture and protecting natural resources.