Misión Biológica de Galicia

This paper explores highly efficient cooperative strategies for population-based parallel metaheuristics, focusing on the integration of shared memory and Remote Memory Access (RMA) operations provided by MPI-3. Most parallel metaheuristic proposals use island-based models with point-to-point communications in their cooperative strategies. These communications can saturate the network and buffers by sending information that often will not be used at the destination, thus resulting in a waste of resources when dealing with these types of applications. In this paper we evaluate other alternative communication protocols that use shared memory windows and RMA operations. Under these new models, the movement of information over the network is on-demand and requested by the source, maximizing resource efficiency. Although the approaches and descriptions in the paper are generic, a particular metaheuristic, the Ant Colony Optimization (ACO), is used to carry out the experiments. The results obtained draw interesting conclusions that can serve to guide the future parallelization of other metaheuristics.

Abstract Aims Trichoderma is a filamentous fungus beneficial to crops and widely used as biofungicide. Its mechanisms of action as a biological control agent against phytopathogenic fungi include mycoparasitism and the induction of plant defense responses. On the other hand, Sclerotinia sclerotiorum is an important pathogen for Brassica crops, effectively suppressed by Trichoderma . The aim of this work is to determine whether T. hamatum can release elicitors from the cell wall of S. sclerotiorum that activate plant systemic defenses against the pathogen. Methods Liquid fermentation of T. hamatum on S. sclerotiorum mycelium was performed. In the resulting fungal filtrates, chitinase and β-endoglucanase activities were quantified, along with the amounts of glucosamine and glucan oligomers produced. These filtrates were subsequently applied to the roots of broccoli plants ( Brassica oleracea var. italica ), which were later foliar-infected with the pathogen. Lesions produced were measured and different systemic defensive responses were evaluated through hormonomics, glucosinolate profiling and non-targeted metabolomics. Results In fungal filtrates of T. hamatum cultured on S. sclerotiorum , chitinase (7.56–8.32 units/mL) and β-endoglucanase (3.45 units/mL) activity was determined. These filtrates also contained the highest amounts of glucosamine (0.75 g/L) and glucan oligomers (43.8 g/L). When applied to broccoli plants, the filtrates triggered a systemic defense response that was effective against the pathogen. This response was mediated by the hormones jasmonic acid, isopentenyladenine and ethylene, leading to the accumulation of antifungal compounds in the leaves, including glucobrassicin, niacin and several fatty acids. This defensive induction was not observed with glucosamine oligomers. Conclusions Therefore, T. hamatum releases glucan oligomers from the cell wall of S. sclerotionum which may act as potential elicitors of systemic plant defenses. Highlights • T. hamatum releases oligomers from the S. sclerotiorum cell wall by enzymatic action. • Glucan oligomers, but not glucosamine oligomers, induce systemic plant resistance. • Systemic resistance is mediated by ethylene/jasmonic acid, a response to necrotrophs. • Reduced S. sclerotiorum -foliar infection is due to an accumulation of glucobrassicin and niacin. • Trichoderma is able to release plant defense elicitors from the pathogen cell wall.

In the southwestern region of Asturias (Northern Spain) lies one of the few mountainous viticulture areas in the world, representing only 5% of global viticulture. The complex topography and differences in altitude, slope, and orientation of mountainous viticulture areas create highly variable microclimates even among nearby plots, with distinct mean temperatures, relative humidity, and solar radiation. These factors strongly influence grape and wine quality, as well as polyphenol concentration. Several production parameters and basic chemical characteristics of must were analyzed over multiple years, along with polyphenol content, in grapes from the same clones of Albarín Blanco and Verdejo Negro (autochthonous genotypes of this viticultural area), grown in geographically close vineyards with different topographies and microclimates. The results revealed significant differences in all analyzed parameters. Both varieties showed polyphenol concentrations slightly higher than those reported in the scientific literature, which may be related to the typical conditions of mountain viticulture or intrinsic genetic factors of these varieties. The best grape and must quality, regardless of variety, was obtained in plots located in sunny, well-ventilated areas with steep slopes and low-fertility soils. These plots exhibited higher potential alcohol content and greater concentrations of anthocyanins, hydrocarbons, and total polyphenols. When comparing varieties, Verdejo Negro showed the highest levels of anthocyanins, flavonols, and total polyphenols, whereas Albarín Blanco exhibited the highest concentrations of total phenolics and hydrocarbons.

Abstract Model-based design in synthetic biology is limited by the lack of quantitative, mechanistically interpretable biopart parameters that remain valid across genetic and physiological contexts. This limitation is particularly acute for transcriptional units, whose expression phenotypes emerge from nonlinear coupling between plasmid copy number, transcription, translation, and host resource allocation. Here we introduce a context- and host-aware framework for the absolute characterisation of gene expression bioparts embedded in combinatorial libraries of constitutive transcriptional units. Our approach leverages a digital twin of Escherichia coli conditioned on experimentally measured growth rate, used as a low-dimensional physiological proxy for cellular state. By embedding this growth-conditioned digital twin in a model-in-the-loop identification strategy, host–circuit interactions are explicitly accounted for and decoupled from intrinsic biopart properties. Using structured combinatorial libraries, we identify biophysically interpretable and transferable parameters for plasmid origins, promoters, and ribosome binding sites. In particular, we uncover an intrinsic translation initiation capacity of ribosome binding sites that remains invariant across genetic contexts and growth conditions, while context-dependent translation rates emerge as physiological projections of this invariant descriptor. This intrinsic parameterisation enables accurate prediction of protein synthesis across diverse host states, supports incremental and patchwork library expansion, and reveals localized failures of modularity that are obscured by phenotype-only characterisation. Together, these results establish a principled link between DNA sequence, intrinsic biopart parameters, and circuit-level phenotypes, providing a scalable and host-aware foundation for predictive design in synthetic biology.

Castanea sativa, a species of high ecological and economic relevance in Europe, faces severe threats from root rot caused by Phytophthora cinnamomi. To explore genetic strategies for enhancing disease tolerance, we investigated the functional role of a chestnut gene homologous to Ginkgo biloba's ginkbilobin-2 (Cast_Gnk2-like), known for its antifungal properties. Using Agrobacterium tumefaciens-mediated transformation, the Cast_Gnk2-like gene was introduced into somatic embryos from two embryogenic chestnut lines. Transformation efficiency was genotype-dependent, and varied from 14.2% to 2.5%. Twelve independent transgenic lines were confirmed by PCR, and each was estimated to carry a single copy of the transgene. Gene expression analysis revealed significant Cast_Gnk2-like transcript levels in two transgenic lines. Following cold storage and germination treatment, viable transgenic plants were regenerated. Disease tolerance assays demonstrated that Cast_Gnk2-like overexpression significantly reduced root necrosis and symptom severity, indicating enhanced tolerance to P. cinnamomi. These findings highlight the potential of targeted gene overexpression to improve disease resilience in chestnut through genetic engineering.

Abstract Background Fire regimes are rapidly shifting due to climate change and increasing vegetation flammability, with these dynamics often intensified in areas undergoing widespread rural abandonment, a trend particularly evident in mountainous landscapes of sub-Mediterranean Europe. We assessed avian community responses, including post-fire beta diversity, during the first breeding season following a megafire—the largest recorded in the region—within a depopulated mountain landscape in northwestern Iberia, located in a poorly studied transitional biogeographic zone. We employed a stratified sampling design across major habitat types to survey bird communities and quantify fire attributes and vegetation structure, combining field-based measurements with satellite-derived spectral indices. Results We recorded 2,928 individuals representing 56 bird species, classified into multiple functional guilds. Fire severity was the main negative driver of community structure and composition, significantly impacting most functional groups. In contrast, spatial heterogeneity in fire severity fostered a broader range of ecological niches, enhancing the coexistence of diverse guilds and buffering the immediate effects of high fire severity. Postfire vegetation structure was a key determinant of community reassembly: snag-rich stands, unburned forest patches, and early post-fire open habitats facilitated both avian persistence and recolonization. These components also provided critical resources for highly specialized guilds, including cavity-nesting and open-habitat species. Bird community composition differed significantly but weakly between burned and unburned areas, and fire heterogeneity had a strong positive effect on post-fire beta diversity only when interacting with post-fire habitat structure. Conclusions Our findings demonstrate that fire attributes alone cannot account for short-term avian responses; rather, their interaction with pre-fire structural legacies is critical to understanding community reassembly. The conservation of snag-rich stands, early-successional open habitats, and unburned forest refugia—alongside the maintenance of fine-scale heterogeneity—should be prioritized to support post-fire bird community recovery in abandoned sub-Mediterranean mountain landscapes.

Abstract Plant phenolics play a key role in plant defence mechanisms against both biotic and abiotic stressors. However, their responses to environmental variables and grazing pressure across large geographical scales remain poorly understood. Using data from a global survey of 325 plots spanning six continents, we examined how climatic factors, soil properties, leaf nutrients and grazing pressure shape leaf phenolic concentration in 1854 plant species (1280 herbaceous and 574 woody) across global drylands. Our findings reveal that leaf phenolic concentration in herbaceous plants was mainly influenced by grazing pressure and its interactions with leaf nitrogen and iron, which together explained over 50% of observed variation across global drylands. Conversely, phenolic concentration in woody plants was strongly associated with climatic factors, particularly mean annual precipitation (MAP) and mean annual temperature (MAT), which accounted for 80% of the observed variation. While MAP had a positive effect on leaf phenolic concentration in woody plants, grazing pressure buffered this relationship by reducing the influence of MAP. Synthesis. Our study advances the understanding of how biotic and abiotic stressors shape plant defence strategies in global drylands. Our findings shed novel insights about how plant secondary metabolites and their associated functions shift in response to changes in climate and grazing pressure, two key global change drivers with significant implications for ecosystem resilience in drylands worldwide.

Abstract Herbivory can affect the soil microbiome, creating legacies that affect plant resistance, but how these effects vary by feeding guild and the plant traits involved remain underexplored. We tested how soil legacies created by a leaf‐chewing caterpillar ( Spodoptera exigua ) and a sap‐feeding aphid ( Aphis gossypii ) influence resistance in Baccharis salicifolia by evaluating changes in plant traits and soil microbial diversity. We conditioned soil with three herbivory treatments on B. salicifolia : caterpillar herbivory, aphid herbivory or control (no herbivory). Then, we grew new plants in sterile soil inoculated with 10% conditioned soil from each treatment and conducted resistance bioassays, measured plant nutritional and defence traits and analysed microbial diversity. Caterpillar, but not aphid herbivory, created legacies that affected resistance to both herbivores in opposite directions: plants in caterpillar‐conditioned soil had 16% smaller aphid colonies than plants in control soil, and a 76% increase in caterpillar performance relative to aphid‐conditioned soil, suggesting guild‐specific trade‐offs in resistance. These plants also showed a 12% higher carbon‐to‐nitrogen ratio than plants in control soil, mediating resistance to the aphid but not to the caterpillar. Herbivory did not affect microbial taxonomic diversity, suggesting shifts in microbiome biomass or function underlie the observed effects. Our findings highlight that herbivory‐induced soil legacies are guild‐specific and can alter plant resistance via trait‐mediated pathways, underscoring the importance of considering herbivore identity when evaluating above–below‐ground feedbacks. Read the free Plain Language Summary for this article on the Journal blog.

Main conclusionSoil application of entomopathogenic nematodes enhanced the growth and modulated the aboveground defenses in potato plants, while interactions with mycorrhizal fungi shaped the volatile emissions and herbivory, underscoring the nematodes as primary drivers in multi-mutualistic systems.Plants frequently engage with multiple belowground mutualists simultaneously, yet the outcomes of such multi-partner associations for plant traits and herbivore resistance remain poorly understood. In this study, we investigated the independent and combined effects of arbuscular mycorrhizal fungi (AMF; Rhizophagus irregularis) and entomopathogenic nematodes (EPNs; Steinernema carpocapsae and Heterorhabditis bacteriophora) on the growth and defense phenotype of potato (Solanum tuberosum) plants. Using a fully factorial experimental design, we assessed the plant height, foliar phenolic content, constitutive volatile organic compound (VOC) emissions, and leaf damage by chewing herbivores. We found that EPNs alone enhanced plant height and reduced flavonoid concentrations, consistent with a potential shift in growth–defense allocation. AMF inoculation had no significant main effects on any measured trait but interacted with EPNs in a species-specific manner. Notably, mycorrhization increased VOC emission only in the presence of H. bacteriophora, while co-inoculation with AMF and S. carpocapsae significantly reduced herbivore damage—a response not observed in either single-symbiont treatment. These findings highlight the non-additive and context-dependent nature of belowground mutualist interactions, with distinct outcomes governed by the identity of the EPN. To our knowledge, this is among the first documented cases where aboveground herbivory is attenuated through a context-specific interaction between two root-associated mutualists. Overall, our results highlight the ecological significance of considering species-specific, multi-mutualist interactions in shaping plant traits and suggest that combining functionally distinct symbionts may offer a novel approach to enhancing crop resilience in sustainable agriculture.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00425-025-04877-w.