Gwilym Lewis

Abstract After many decades of effective control of stem rust caused by the Puccinia graminis f.sp. tritici, (hereafter Pgt) the reported emergence of race TTKSK/Ug99 of Pgt in Uganda reignited concerns about epidemics worldwide because ∼90% of world wheat cultivars had no resistance to the new race. Since it was initially detected in Uganda in 1998, Ug99 variants have now been identified in thirteen countries in Africa and the Middle East. Stem rust has been a major problem in the past, and concern is increasing about the risk of return to Central and East Asia. Whilst control programs in North America and Europe relied on the use of resistant cultivars in combination with eradication of barberry (Berberis spp.), the alternate host required for the stem rust pathogen to complete its full lifecycle, the focus in East Asia was principally on the use of resistant wheat cultivars. Here, we investigate potential airborne transmission pathways for stem rust outbreaks in the Middle East to reach East Asia using an integrated modelling framework combining estimates of fungal spore deposition from an atmospheric dispersion model, environmental suitability for spore germination, and crop calendar information. We consider the role of mountain ranges in restricting transmission pathways, and we incorporate a representation of a generic barberry species into the lifecycle. We find viable transmission pathways to East Asia from the Middle East to the north via Central Asia and to the south via South Asia and that an initial infection in the Middle East could persist in East Asia for up to three years due to the presence of the alternate host. Our results indicate the need for further assessment of barberry species distributions in East Asia and appropriate methods for targeted surveillance and mitigation strategies should stem rust incidence increase in the Middle East region.

Premise Cleomaceae is an important model clade for studies of evolutionary processes including genome evolution, floral form diversification, and photosynthetic pathway evolution. Diversification and divergence patterns in Cleomaceae remain tangled as research has been restricted by its worldwide distribution, limited genetic sampling and species coverage, and a lack of definitive fossil calibration points.MethodsWe used target sequence capture and the Angiosperms353 probe set to perform a phylogenetic study of Cleomaceae. We estimated divergence times and biogeographic analyses to explore the origin and diversification of the family. Seed morphology across extant taxa was documented with multifocal image‐stacking techniques and morphological characters were extracted, analyzed, and compared to fossil records.ResultsWe recovered a well‐supported and resolved phylogenetic tree of Cleomaceae generic relationships that includes 236 (~86%) species. We identified 11 principal clades and confidently placed Cleomella as sister to the rest of the family. Our analyses suggested that Cleomaceae and Brassicaceae diverged ~56 mya, and Cleomaceae began to diversify ~53 mya in the Palearctic and Africa. Multiple transatlantic disjunct distributions were identified. Seeds were imaged from 218 (~80%) species in the family and compared to all known fossil species.ConclusionsOur results represent the most comprehensive phylogenetic study of Cleomaceae to date. We identified transatlantic disjunctions and proposed explanations for these patterns, most likely either long‐distance dispersals or contractions in latitudinal distributions caused by climate change over geological timescales. We found that seed morphology varied considerably but mostly mirrored generic relationships.

It would be advantageous to grow legume forage crops in order to increase the productivity and sustainability of sloped croplands in Hamkyongbukdo. In particular, the identification of potential cultivation areas for alfalfa in the given region could aid decision-making on policies and management related to forage crop production in the future. This study aimed to analyze the climate suitability of alfalfa in Hamkyongbukdo under current and future climate conditions using the Fuzzy Union model. The climate suitability predicted by the Fuzzy Union model was compared with the actual alfalfa cultivation area in the northern United States. Climate data obtained from 11 global climate models were used as input data for calculation of climate suitability in the study region to examine the uncertainty of projections under future climate conditions. The area where the climate suitability index was greater than a threshold value (22.6) explained about 44% of the variation in actual alfalfa cultivation areas by state in the northern United States. The climatic suitability of alfalfa was projected to decrease in most areas of Hamkyongbukdo under future climate scenarios. The climatic suitability in Onseong and Gyeongwon County was analyzed to be over 88 in the current climate conditions. However, it was projected to decrease by about 66% in the given areas by the 2090s. Our study illustrated that the impact of climate change on suitable cultivation areas was highly variable when different climate data were used as inputs to the Fuzzy Union model. Still, the ensemble of the climate suitability projections for alfalfa was projected to decrease considerably due to summer depression in Hamkyongbukdo. It would be advantageous to predict suitable cultivation areas by adding soil conditions or to predict the climate suitability of other leguminous crops such as hairy vetch, which merits further studies.

Background and Aims: Parasitic plants represent approximately 1% of the world’s angiosperm diversity. The highest richness of parasitic plant species among angiosperms belongs to Orobanchaceae, the only family with three main nutritional stages: autotrophic, hemiparasitic, and holoparasitic. Hemiparasitic genera are the most diverse, unstudied, and sometimes neglected within Orobanchaceae. Pedicularideae, the largest tribe of hemiparasitic taxa in Orobanchaceae, contains several poorly known genera. One of these is Lamourouxia, a genus of 30 species distributed throughout the Americas, but mostly endemic to Mexico. Due to the lack of knowledge about the biogeographic patterns, ende-mism, and conservation status of Lamourouxia species, the objectives of this study were to estimate their species richness and endemism, determine the areas of endemismin the Americas, and assess their conservation status.Methods: Applying a taxonomic revision of physical and digitized herbaria specimens, citizen science observations, and scientific open access databases, we conducted biogeo-graphic analyses for the whole genus. Moreover, the conservation status of all Lamourouxia species was assessed following the IUCN Red List guidelines.Key results: The highest species richness, highest weighted endemism, and corrected weighted endemism values occurred in southern Mexico. Three areas of endemicity were distributed throughout western Mexico. Four species were classified as Endangered (EN), and three as Critically Endangered (CR) according to the IUCN risk categories. Endemic and rarely recorded Lamourouxia species were mostly distributed in unprotected areas in the Sierra Madre del Sur, Mexico.Conclusions: The Mexican Transition Zone is the center of diversification of Lamourouxia, and one third of the genus is endemic to this region. It is strongly encouraged to carry out actions to conserve threatened species of Lamourouxia, which are distributed in the Sierra Madre del Sur, the biogeographic province with the highest number of endemic species in Mexico.

Given the high number of non-native plants that are being introduced worldwide and the time required to process formal pest risk analyses, a framework for the prioritization of management actions is urgently required. We therefore propose a framework for a replicable and standardized prioritization for management actions (eradication, control and monitoring) of invasive non-native plants, combining expert knowledge, current and future climatic suitability estimated by species distribution models (SDMs), clustering and ordination techniques. Based on expert consultation and using Italy as case study, invasive non-native plant species were selected and three categories of management actions were identified: eradication, control and containment, and monitoring. Finally, two further classes of priorities were proposed for each of the management actions: “high” and “low” priority. Overall, SDMs highlighted a high and very high suitability for Continental and Mediterranean bioregions for most invasive plants. Cluster analysis revealed three distinct clusters with varying levels of suitability for the Italian bioregions. Cluster 1 exhibited a higher suitability across all Italian bioregions, whereas non-native plants grouped in Cluster 2 predominantly featured high suitability in Mediterranean areas. Finally, Cluster 3 showed the lowest suitability values. Two ordination analysis highlighted the variability in bioclimatic suitability for each non-native plant within each cluster, as well as their current distribution pattern. Lastly, a third ordination, integrating bioclimatic suitability and spatial patterns, has allowed the differentiation of management actions for each non-native plant at both national and bioregional scales. Specifically, seven non-native plants were earmarked for eradication action, six for monitoring action, while the remaining species were deemed suitable for control and containment. Our results and the methodology proposed meet the demand for replicable new early warning tools; that is to predict the location of new outbreaks, to establish priorities for eradication, control and containment, and to monitor invasive non-native species.

AbstractAbstract. neighboring countries. Recently, an increase in biological surveys and access to natural preserves has led to a better understanding of species distributions in Nicaragua and across Central America. Here, we provide new departmental records for three species of didelphid, 18 chiropterans (Phyllostomidae, Molossidae, Vespertilionidae), one geomyid, and one mustelid from 21 sites across the country. This work underscores the need for additional sampling across Nicaragua to fill gaps in the known distribution of many species. This information can facilitate or inform conservation actions in established and proposed preserves in Nicaragua.

Wild food plants (WFPs) are important components of the diet and a source of income for local communities in semiarid regions, given that these populations are commonly characterized by high socioeconomic vulnerability and dependence on natural resources for subsistence. In periods of food scarcity and crop failure, WFPs emerge as strategic resources for ensuring food and nutrition security. However, these little-researched plants may also be affected by climate change. Here, our objective was to determine the spatiotemporal dynamics of WFPs in the Brazilian semiarid and evaluate their potential availability in future climate change scenarios. We constructed habitat suitability models for economically and nutritionally important WFPs used in this region and projected future scenarios (2041–2060). Furthermore, we determined the geographical distribution, species richness, and composition (on local and regional scales) of WFPs in current and future scenarios. Our results showed that WFPs exhibited varied responses to climate change. The more pessimistic the future scenario, the greater the negative effects. Most WFP species exhibited a reduction in climatically suitable areas in future scenarios, resulting in a shrinkage of geographical ranges, a reduction in species richness, and alterations in community composition. These changes could have important implications for economic development, subsistence, and food and nutrition security in the region. Our findings offer insights that can guide actions for adaptation and mitigating the effects of climate change and promoting species conservation not only in the Brazilian semiarid but also in other semiarid regions worldwide.

Cerrado is a large and heterogeneous ecoregion in the Neotropics marked by the fire‐prone savanna vegetation, to which succulent lineages are usually not associated due to this adverse condition. However, recent studies have highlighted the importance of Cerrado as an ancestral range for the origin, dispersal and in situ diversification of remarkable lineages of South American cacti. In this perspective, we explore the implications of these occurrences in the Cerrado, shedding light on a frequently overlooked aspect of this ecoregion—the role of scattered rocky outcrop habitats acting as micro‐refuges for fire‐sensitive lineages. We show that most cacti occurrences are associated with patches of rock outcrops across the Cerrado. In contrast, when terricolous, a few disparate and not closely related species can develop underground structures or present a specialized habit that facilitates their presence as a putative response to fire—reinforcing the evolutionary lability of fire adaptation in Cerrado lineages. Despite some notable endemisms, several occurrences are from species with core distributions in adjacent ecoregions (e.g. Caatinga and Chaco), demonstrating the permeability of Cerrado, which can act concomitantly as a biogeographical barrier (especially due to its fire‐prone habitats) and as a corridor for biota interchange. Finally, we stress that Cerrado heterogeneity, often leading to different circumscriptions, is a relevant issue when studying and characterizing Neotropical biota, which must be further explored and considered to assess the evolutionary assembly of the biomes involved.

Aim To test the hypothesis that adaptive shifts leading to the assembly of tropical savannas involved coordination between bark and wood traits and to understand the underlying mechanisms.LocationTropical South America.TaxonAngiosperms (woody).MethodsWe compiled data on three bark traits (total, inner and outer relative bark thickness), wood density, maximum height, five secondary xylem traits and on species' habitat information (light environment, climate, soil and fire history) for Neotropical savanna, forest and generalist species (biome groups). We tested for pairwise and multivariate associations among traits across species and if biome group and habitat conditions explained species positions along the resulting strategy axes.ResultsTraits covaried along four different axes. The first axis was consistent with a trade‐off between fire (thick barks) and shade tolerance (low bark to diameter ratio, high vessel density) and contributed to differentiate the three biome groups according to the preference for shaded environments. Forest species also differed from savanna and generalist species in a separate axis by being more resource acquisitive. Maximum height and wood density did not strongly trade‐off with bark thickness, although maximum height was negatively covaried with relative outer bark thickness. Preference for shaded conditions was the main driver of variation in the two principal strategy axes, but temperature, fire and soil sand content also explained differences in plant stature between savanna and generalist species.Main ConclusionsAllocation to bark is constrained by trade‐offs with wood, opposing shade‐tolerant and acquisitive forest species to fire‐resistant and conservative savanna species. Rather than a single strategy axis, three axes are necessary to understand the functional differences among savanna, forest and generalist species. Because two of these axes are controlled by light availability, the associated traits tend to covary in space and time, but not across species.

Aim Species occurrence data are valuable information that enables one to estimate geographical distributions, characterize niches and their evolution, and guide spatial conservation planning. Rapid increases in species occurrence data stem from increasing digitization and aggregation efforts, and citizen science initiatives. However, persistent quality issues in occurrence data can impact the accuracy of scientific findings, underscoring the importance of filtering erroneous occurrence records in biodiversity analyses.InnovationWe introduce an R package, occTest, that synthesizes a growing open‐source ecosystem of biodiversity cleaning workflows to prepare occurrence data for different modelling applications. It offers a structured set of algorithms to identify potential problems with species occurrence records by employing a hierarchical organization of multiple tests. The workflow has a hierarchical structure organized in testPhases (i.e. cleaning vs. testing) that encompass different testBlocks grouping different testTypes (e.g. environmental outlier detection), which may use different testMethods (e.g. Rosner test, jacknife,etc.). Four different testBlocks characterize potential problems in geographic, environmental, human influence and temporal dimensions. Filtering and plotting functions are incorporated to facilitate the interpretation of tests. We provide examples with different data sources, with default and user‐defined parameters. Compared to other available tools and workflows, occTest offers a comprehensive suite of integrated tests, and allows multiple methods associated with each test to explore consensus among data cleaning methods. It uniquely incorporates both coordinate accuracy analysis and environmental analysis of occurrence records. Furthermore, it provides a hierarchical structure to incorporate future tests yet to be developed.Main conclusionsoccTest will help users understand the quality and quantity of data available before the start of data analysis, while also enabling users to filter data using either predefined rules or custom‐built rules. As a result, occTest can better assess each record's appropriateness for its intended application.