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CRISPR-based gene-drives targeting the gene doublesex in the malaria vector Anopheles gambiae effectively suppressed the reproductive capability of mosquito populations reared in small laboratory cages. To bridge the gap between laboratory and the field, this gene-drive technology must be challenged with vector ecology. Here we report the suppressive activity of the gene-drive in age-structured An. gambiae populations in large indoor cages that permit complex feeding and reproductive behaviours. The gene-drive element spreads rapidly through the populations, fully supresses the population within one year and without selecting for resistance to the gene drive. Approximate Bayesian computation allowed retrospective inference of life-history parameters from the large cages and a more accurate prediction of gene-drive behaviour under more ecologically-relevant settings. Generating data to bridge laboratory and field studies for invasive technologies is challenging. Our study represents a paradigm for the stepwise and sound development of vector control tools based on gene-drive. Experimental analysis of gene drive population dynamics has mostly been limited to small cage trials. Here the authors, to fill the gap between lab based studies and field studies, use large indoor cages and see population suppression without the emergence of resistant alleles

Common walnut (Juglans regia L) is an economically important species cultivated worldwide for its high-quality wood and nuts. It is generally accepted that after the last glaciation J. regia survived and grew in almost completely isolated stands in Asia, and that ancient humans dispersed walnuts across Asia and into new habitats via trade and cultural expansion. The history of walnut in Europe is a matter of debate, however. In this study, we estimated the genetic diversity and structure of 91 Eurasian walnut populations using 14 neutral microsatellites. By integrating fossil pollen, cultural, and historical data with population genetics, and approximate Bayesian analysis, we reconstructed the demographic history of walnut and its routes of dispersal across Europe. The genetic data confirmed the presence of walnut in glacial refugia in the Balkans and western Europe. We conclude that human-mediated admixture between Anatolian and Balkan walnut germplasm started in the Early Bronze Age, and between western Europe and the Balkans in eastern Europe during the Roman Empire. A population size expansion and subsequent decline in northeastern and western Europe was detected in the last five centuries. The actual distribution of walnut in Europe resulted from the combined effects of expansion/contraction from multiple refugia after the Last Glacial Maximum and its human exploitation over the last 5,000 years.

• Premise of the study: Large-scale studies on the genetic diversity of forest trees are relevant for the inventory, conservation, and management of genetic resources and provide an insight into the geographical origins of the species. This approach is appropriate to use with Castanea sativa, a tree of great economic importance and the only species from the genus Castanea in Europe. The history of C. sativa was deduced from fossil pollen data, but the large-scale genetic structure of this species needs to be elucidated. We evaluated the genetic diversity of C. sativa to define previously unclarified genetic relationships among the populations from Turkey and those from Greece and western Europe. The influence of natural events such as glaciations and human impact in terms of species distribution are discussed.• Methods: Wild chestnut trees (779) were sampled in 31 European sites. Six polymorphic microsatellites were used for the analysis. A set of measures of intra- and interpopulation genetic statistics were calculated. The population structure was inferred by using a Bayesian approach.• Key results: The population structure showed a genetic divergence between the eastern (Greek and Turkish) and western (Italian and Spanish) populations. Two gene pools and a zone of gene introgression in Turkey were revealed.• Conclusions: The inferred population structure shows a strong geographical correspondence with the hypothesized glacial refugia and rules out the migration of the chestnut from Turkey and Greece to Italy. The homogeneous gene pool observed in Italy and Spain could have been originated from common refugia along with human-mediated colonization.

Common walnut (Juglans regia L) is an economically important species cultivated worldwide for its wood and nuts. It is generally accepted that J. regia survived and grew spontaneously in almost completely isolated stands in its Asian native range after the Last Glacial Maximum. Despite its natural geographic isolation, J. regia evolved over many centuries under the influence of human management and exploitation. We evaluated the hypothesis that the current distribution of natural genetic resources of common walnut in Asia is, at least in part, the product of ancient anthropogenic dispersal, human cultural interactions, and afforestation. Genetic analysis combined with ethno-linguistic and historical data indicated that ancient trade routes such as the Persian Royal Road and Silk Road enabled long-distance dispersal of J. regia from Iran and Trans-Caucasus to Central Asia, and from Western to Eastern China. Ancient commerce also disrupted the local spatial genetic structure of autochthonous walnut populations between Tashkent and Samarkand (Central-Eastern Uzbekistan), where the northern and central routes of the Northern Silk Road converged. A significant association between ancient language phyla and the genetic structure of walnut populations is reported even after adjustment for geographic distances that could have affected both walnut gene flow and human commerce over the centuries. Beyond the economic importance of common walnut, our study delineates an alternative approach for understanding how the genetic resources of long-lived perennial tree species may be affected by the interaction of geography and human history.

Microbial biostimulants are increasingly proposed as sustainable tools to enhance crop performance and resilience under climate change. However, their ecophysiological effects and underlying mechanisms remain insufficiently understood, particularly in woody perennial species. This study investigated the effects of MICOSAT F ® microbial biostimulant on growth and ecophysiological traits of two-year-old Olea europaea L. cv. Leccino plants under controlled greenhouse conditions. For the first time, we integrated agronomic measurements with dendrochronological analyses and intra-annual assessments of carbon and nitrogen concentration (C%, N%) and their stable isotope composition (δ¹³C, δ¹ 5 N) in tree rings. Biostimulant-treated trees exhibited significantly larger stem diameter, height, lateral branching, and total biomass compared with controls. Treated trees showed lower stem wood C%, suggesting increased C allocation to non-structural carbohydrates and belowground symbionts. Furthermore, treated trees displayed significantly depleted δ¹³C values with reduced interannual variation, indicating enhanced stomatal conductance and more stable photosynthetic discrimination. Depleted δ¹ 5 N signatures reflected a shift toward microbially-mediated N acquisition pathways rather than increased absolute N availability. These findings demonstrate that MICOSAT F ® biostimulant fundamentally alters plant C and N metabolism, promoting growth while enhancing physiological stability - key traits for potential climate resilience in sustainable olive cultivation systems.

Alnus cordata is an endemic tree species native to the Southern Italian Apennines and north‐eastern Corsica, renowned for its ecological significance. Climate change projections for the Mediterranean basin indicate range shifts and increased fragmentation for many forest trees, including A. cordata. Hybridization with the sympatric A. glutinosa in the central part of its Italian native range may also influence the genetic structure and conservation priorities for A. cordata. A comprehensive conservation strategy is needed to preserve its genetic resources in Italy. We analyzed the genetic diversity, population structure, and extent of hybridization with A. glutinosa in 23 A. cordata forest stands across its native Italian range using nuclear microsatellites. Habitat suitability was modeled under current and future climate scenarios using an ensemble forecasting approach. Conservation prioritization was guided by a genetically informed Reserve Selection analysis in DIVA‐GIS to identify areas of high conservation value and address gaps in genetic resource representation. Italian alder populations exhibit low genetic diversity, which decreases towards the southern latitudinal margins of the peninsula. Hybridization and introgression with Alnus glutinosa have a geographically localized impact on the genetic variation within A. cordata populations. Local increases in private allelic richness do not alter the spatial genetic structure of A. cordata, but they help mitigate the risk of severe genetic erosion. A significant proportion of the species' genetic diversity is effectively preserved through in situ conservation. Model projections under future climate scenarios indicate a substantial decline in habitat suitability for A. cordata stands with high priority for in situ conservation. This highlights the need for complementary strategies, including ex situ conservation measures. Our study highlights the importance of integrating genetic analyses, habitat suitability modeling, and spatial prioritization techniques for effective conservation planning of A. cordata in the face of climate change across the Mediterranean. Alnus cordata is an endemic tree species native to the Southern Italian Apennines and north‐eastern Corsica, renowned for its ecological significance. We analyzed the genetic diversity, population structure, and extent of hybridization with A. glutinosa in 23 A. cordata forest stands across its native Italian range. Conservation prioritization was guided by a genetically informed Reserve Selection analysis in DIVA‐GIS to identify areas of high conservation value and address gaps in genetic resource representation.

Biogenic fraction of airborne PM10 which includes bacteria, viruses, fungi and pollens, has been proposed as one of the potential causes of the PM10 toxicity. The present study aimed to provide a comprehensive understanding of the microbial community variations associated to PM10, and their main local sources in the surrounding environment in three urban sites of Rome, characterized by differential pollution rate: green area, residential area and polluted area close to the traffic roads. We combined high-throughput amplicon sequencing of the bacterial 16S rRNA gene and the fungal internal transcribed spacer (ITS) region, with detailed chemical analysis of particulate matter sampled from air, paved road surfaces and leaf surfaces of Quercus ilex. Our results demonstrated that bacterial and fungal airborne communities were characterized by the highest alpha-diversity and grouped separately from epiphytic and road dust communities. The reconstruction of source-sink relationships revealed that the resuspension/deposition of road dust from traffic might contribute to the maximum magnitude of microbial exchanges. The relative abundance of extremotolerant microbes was found to be enhanced in epiphytic communities and was associated to a progressively increase of pollution levels as well as opportunistic human pathogenicity in fungal communities.

The Asian chestnut gall wasp (ACGW) (Hymenoptera Dryocosmus kuriphilus Yasumatsu) is a severe pest of sweet chestnut (Castanea sativa Mill.) with a strong impact on growth and nut production. A comparative field trial in Central Italy, including provenances from Spain, Italy, and Greece, was screened for ACGW infestation over consecutive years. The Greek provenance Hortiatis expressed a high proportion of immune plants and was used to perform a genome-wide association study based on DNA pool sequencing (Pool-GWAS) by comparing two DNA pools from 25 susceptible and 25 resistant plants. DNA pools were sequenced with 50X coverage depth. Sequence reads were aligned to a C. mollissima reference genome and the pools were compared to identify SNPs associated with resistance. Twenty-one significant SNPs were identified and highlighted a small genomic region on pseudochromosome 3 (Chr 3), containing 12 candidate genes of three gene families: Cytochrome P450, UDP-glycosyltransferase, and Rac-like GTP-binding protein. Functional analyses revealed a putative metabolic gene cluster related to saccharide biosynthesis in the genomic regions associated with resistance that could be involved in the production of a toxic metabolite against parasites. The comparison with previous genetic studies confirmed the involvement of Chr 3 in the control of resistance to ACGW.

Sweet chestnut is a tree of great economic (fruit and wood production), ecological, and cultural importance in Europe. A large-scale landscape genetic analysis of natural populations of sweet chestnut across Europe is applied to (1) evaluate the geographic patterns of genetic diversity, (2) identify spatial coincidences between genetic discontinuities and geographic barriers, and (3) propose certain chestnut populations as reservoirs of genetic diversity for conservation and breeding programs. Six polymorphic microsatellite markers were used for genotyping 1608 wild trees sampled in 73 European sites. The Geostatistical IDW technique (ArcGIS 9.3) was used to produce maps of genetic diversity parameters (He, Ar, PAr) and a synthetic map of the population membership (Q value) to the different gene pools. Genetic barriers were investigated using BARRIER 2.2 software and their locations were overlaid on a Digital Elevation Model (GTOPO30). The DIVA-GIS software was used to propose priority areas for conservation. High values of genetic diversity (He) and allelic richness (Ar) were observed in the central area of C. sativa ’s European distribution range. The highest values of private allelic richness (PAr) were found in the eastern area. Three main gene pools and a significant genetic barrier separating the eastern from the central and western populations were identified. Areas with high priority for genetic conservation were indicated in Georgia, eastern Turkey, and Italy. Our results increase knowledge of the biogeographic history of C. sativa in Europe, indicate the geographic location of different gene pools, and identify potential priority reservoirs of genetic diversity.

A biocultural diversity approach integrates plant biology and germplasm dispersal processes with human cultural diversity. An increasing number of studies have identified cultural factors and ethnolinguistic barriers as the main drivers of the genetic diversity in crop plants. Little is known about how anthropogenic processes have affected the evolution of tree crops over the entire time scale of their interaction with humans. In Asia and the Mediterranean, common walnut (Juglans regia L.) and sweet chestnut (Castanea sativa Mill.) have been economically and culturally important crops for millennia; there, in ancient times, they were invested with symbolic and religious significance. In this study, we detected a partial geographic congruence between the ethno‐linguistic repartition of human communities, the distribution of major cognitive sets of word‐related terms, and the inferred genetic clusters of common walnut and sweet chestnut populations across Eurasia. Our data indicated that isolation by distance processes, landscape heterogeneity and cultural boundaries might have promoted simultaneously human language diversification and walnut/chestnut differentiation across the same geographic macro‐regions. Hotspots of common walnut and sweet chestnut genetic diversity were associated with areas of linguistic enrichment in the Himalayas, Trans‐Caucasus, and Pyrenees Mountains, where common walnuts and sweet chestnuts had sustained ties to human culture since the Early Bronze Age. Our multidisciplinary approach supported the indirect and direct role of humans in shaping walnut and chestnut diversity across Eurasia from the EBA (e.g., Persian Empire and Greek–Roman colonization) until the first evidence of active selection and clonal propagation by grafting of both species. Our findings highlighted the benefit of an efficient integration of the relevant cultural factors in the classical genome (G) × environmental (E) model and the urgency of a systematic application of the biocultural diversity concept in the reconstruction of the evolutionary history of tree species. Little is known about how anthropogenic processes have affected the evolution of tree species with a long‐time‐scale history of human utilization such as common walnut (Juglans regia L.) and sweet chestnut (Castanea sativa Mill.). In this study, we evaluated the impact of isolation by distance processes, landscape heterogeneity, and cultural boundaries among human communities on shaping genetic resources of walnut and chestnut across Eurasia. Our findings highlighted the benefit of an efficient integration of the relevant cultural factors in the classical genome (G) × environmental (E) model and the urgency of a systematic application of the biocultural diversity concept in the reconstruction of evolutionary history of tree species