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Soil biodiversity constitutes the biological pillars of ecosystem services provided by soils worldwide. Soil life is threatened by intense agricultural management and shifts in climatic conditions as two important global change drivers which are not often jointly studied under field conditions. We addressed the effects of experimental short-term drought over the wheat growing season on soil organisms and ecosystem functions under organic and conventional farming in a Swiss long term trial. Our results suggest that activity and community metrics are suitable indicators for drought stress while microbial communities primarily responded to agricultural practices. Importantly, we found a significant loss of multiple pairwise positive and negative relationships between soil biota and process-related variables in response to conventional farming, but not in response to experimental drought. These results suggest a considerable weakening of the contribution of soil biota to ecosystem functions under long-term conventional agriculture. Independent of the farming system, experimental and seasonal (ambient) drought conditions directly affected soil biota and activity. A higher soil water content during early and intermediate stages of the growing season and a high number of significant relationships between soil biota to ecosystem functions suggest that organic farming provides a buffer against drought effects.

Global change is causing unprecedented degradation of the Earth’s biological systems and thus undermining human prosperity. Past practices have focused either on monitoring biodiversity decline or mitigating ecosystem services degradation. Missing, but critically needed, are management approaches that monitor and restore species interaction networks, thus bridging existing practices. Our overall aim here is to lay the foundations of a framework for developing network management, defined here as the study, monitoring, and management of species interaction networks. We review theory and empirical evidence demonstrating the importance of species interaction networks for the provisioning of ecosystem services, how human impacts on those networks lead to network rewiring that underlies ecosystem service degradation, and then turn to case studies showing how network management has effectively mitigated such effects or aided in network restoration. We also examine how emerging technologies for data acquisition and analysis are providing new opportunities for monitoring species interactions and discuss the opportunities and challenges of developing effective network management. In summary, we propose that network management provides key mechanistic knowledge on ecosystem degradation that links species- to ecosystem-level responses to global change, and that emerging technological tools offer the opportunity to accelerate its widespread adoption.

The potential of black soldier fly larvae (BSFL) and microalgae (MA) in poultry diets has garnered increasing interest due to their high nutritional value and reduced environmental footprint. BSFL represent a sustainable alternative to conventional protein sources such as soybean meal, whereas MA contributes to improved egg quality, particularly through its enrichment with polyunsaturated fatty acids. This study assessed the effects of BSFL and MA inclusion on the growth performance and egg quality of Rhode Island Red (RIR) laying hens. Three diets were formulated: Diet A (10% BSFL), Diet B (10% BSFL + 2% MA), and Diet C (commercial control). The diets were formulated to meet the age-specific nutrient requirements of RIR hens, according to the National Research Council (NRC, 1994) guidelines. A total of 96 four-week-old chicks were randomly allocated to six pens (n = 16 per pen) and provided ad libitum access to feed and water throughout the trial. The results demonstrated that the inclusion of BSFL and MA significantly influenced the growth rate, onset of lay, and egg characteristics. Hens fed Diet B exhibited the highest average weekly body weight gain (0.034 ± 0.001 kg/week); initiated laying at 20 weeks of age, three weeks earlier than hens on Diets B and C; and produced significantly heavier eggs (51.208 ± 0.511 g). Enhanced eggshell quality and yolk pigmentation were also observed. In addition, Diet B enhanced the nutritional profile of the eggs, yielding a higher albumen protein content (76.546 ± 1.382%DM) and lower lipid concentrations (0.451 ± 0.128%DM). These findings underscore the potential of BSFL and MA as functional feed ingredients for improving poultry performance and egg quality in a sustainable production system.

Agricultural fields are typically simplified ecosystems compared to natural sites, a characteristic that has long‐attracted researchers in Ecology and Evolution. In recent years, there has been a rising interest in understanding how agricultural systems are shaped by evolution in the context of changing agricultural practices by integrating biological information of crop systems. This editorial introduces the special issue “Evolution in agricultural systems,” incorporating the articles published within this issue into three general areas of research: phenotypic and genetic responses to the environment, biotic interactions and the role of microbes. Together, this body of work unveils unforeseen complexity at all levels, from microbes to trophic chains. Understanding such complexity is critical not only to better understand natural systems, but also if we wish to improve the sustainability of the food system.

Climate change can dramatically affect the food web configuration of arthropod communities through its effects on species interactions. We have studied whether these effects could alter the probability of local extinction of three predatory mites naturally associated with the two-spotted spider mite, Tetranychus urticae , in citrus in Spain and, therefore, disrupt the biological control of this phytophagous mite. Laboratory and semi-field results provide evidence that the natural regulation of T. urticae in citrus can be seriously disrupted in a warmer future. On the one hand, T. urticae populations at conditions representative of future hotter and drier summers, could reach higher population densities than forecasted according to its demographic parameters. On the other hand, T. urticae regulation provided by its predators depended on the environmental conditions, was species-specific, and was affected by interspecific interactions. In some cases, one of the predatory mite species in the system could not be recovered. Because there is evidence that the composition of the community under scrutiny is highly sensitive to local habitat conditions, our results can be taken as evidence that local extinctions may occur more frequently in a warmer future and further contribute to an increasingly higher frequency of T. urticae outbreaks.

Climate change is one of the most important factors affecting the phenology, distribution, composition and diversity of organisms. In agricultural systems many pests and natural enemies are arthropods. As poikilotherm organisms, their body temperature is highly dependent on environmental conditions. Because higher trophic levels typically have lower tolerance to high temperatures than lower trophic levels, trends towards increasing local or regional temperatures may affect the strength of predator/prey interactions and disrupt pest control. Furthermore, increasing temperatures may create climate corridors that could facilitate the invasion and establishment of invasive species originating from warmer areas. In this study we examined the effect of environmental conditions on the dynamics of an agro-ecosystem community located in southern Spain, using field data on predator/prey dynamics and climate gathered during four consecutive years. The study system was composed of an ever-green tree species (avocado), an exotic tetranychid mite, and two native species of phytoseiid mites found in association with this new pest. We also present a climatological analysis of the temperature trend in the area of study during the last 28 years, as evidence of temperature warming occurring in the area. We found that the range of temperatures with positive per capita growth rates was much wider in prey than in predators, and that relative humidity contributed to explain the growth rate variation in predators, but not in prey. Predator and prey differences in thermal performance curves could explain why natural enemies did not respond numerically to the pest when environmental conditions were harsh.

Calcium/calmodulin-dependent protein kinase kinase (CaMKK) is required for diverse cellular functions. Mammalian CaMKK activates CaMKs and also the evolutionarily-conserved AMP-activated protein kinase (AMPK). The fission yeast Schizosaccharomyces pombe CaMKK, Ssp1, is required for tolerance to limited glucose through the AMPK, Ssp2, and for the integration of cell growth and division through the SAD kinase Cdr2. Here we report that Ssp1 controls the G2/M transition by regulating the activity of the CaMK Srk1. We show that inhibition of Cdc25 by Srk1 is regulated by Ssp1; and also that restoring growth polarity and actin localization of ssp1-deleted cells by removing the actin-monomer-binding protein, twinfilin, is sufficient to suppress the ssp1 phenotype. These findings demonstrate that entry into mitosis is mediated by a network of proteins, including the Ssp1 and Srk1 kinases. Ssp1 connects the network of components that ensures proper polarity and cell size with the network of proteins that regulates Cdk1-cyclin B activity, in which Srk1 plays an inhibitory role.

Photoselective nets have proven to be effective for aphid pest control as they limit their dispersal ability. However, little is known on the impact of such nets on natural enemies of aphids. In this work, we study the effect of UV-absorbing nets on the syrphid fly Sphaerophoria rueppellii Wiedemann (Diptera: Syrphidae), a commercially available aphid biocontrol agent in Mediterranean horticultural crops. First, we released mature syrphid adults and evaluated density and dispersal of the resulting immatures in a turnip crop grown under either UV-blocking (Bionet) or standard net. Second, we assessed, under controlled conditions, the impact of UV radiation on fitness-related parameters, and on flight behavior of S. rueppellii adults. Results showed that, while syprhid immature density was higher, their dispersion was reduced under Bionet. UV-absorbing nets are known to influence the dispersion pattern of aphids, which may have indirectly conditioned the distribution of their predator S. rueppellii. On the other hand, the type of net had no influence on the performance of adults. We conclude that the use of photoselective nets and the release of syrphid predators such S. rueppellii are compatible strategies to be used in IPM aphid-control programs.

That predators attack and prey defend is an oversimplified view. When size changes during development, large prey may be invulnerable to predators, and small juvenile predators vulnerable to attack by prey. This in turn may trigger a defensive response in adult predators to protect their offspring. Indeed, when sizes overlap, one may wonder 'who is the predator and who is the prey'! Experiments with 'predatory' mites and thrips 'prey' showed that young, vulnerable prey counterattack by killing young predators and adult predators respond by protective parental care, killing young prey that attack their offspring. Thus, young individuals form the Achilles' heel of prey and predators alike, creating a cascade of predator attack, prey counterattack and predator defence. Therefore, size structure and relatedness induce multiple ecological role reversals.

1. When intraguild (IG)-prey are superior to IG-predators in competing for a shared resource, theory predicts coexistence of the IG-prey or the IG-predator with the resource depending on the productivity level: (a) resource and IG prey coexist when productivity is low; (b) IG-predator and resource coexist at high productivity; (c) if IG-prey and IG-predators can coexist, it is only at intermediate productivity levels. 2. We tested the existence of productivity-dependent regions of coexistence using an experimental system of two predatory mites and a shared food source (pollen). 3. At high levels of pollen supply (i.e. high productivity), the IG-predator excluded the IG-prey in most, but not all, cases. The same pattern of exclusion was observed at low productivity, at which the IG-prey was expected to exclude the IG-predator. Therefore, species composition could not be predicted by productivity levels. Instead, our results show that initial conditions affected strongly the outcome of the interaction. 4. We emphasize the need for theory on IG-predation that takes the effects of stage structure, initial conditions and transient dynamics into account.