Science Rendue Possible

Bürger, M., and J. Chory. 2024. A potential role of heat‐moisture couplings in the range expansion of Striga asiatica. Ecology and Evolution 14.

Parasitic weeds in the genera Orobanche, Phelipanche (broomrapes) and Striga (witchweeds) have a devastating impact on food security across much of Africa, Asia and the Mediterranean Basin. Yet, how climatic factors might affect the range expansion of these weeds in the context of global environmental change remains unexplored. We examined satellite‐based environmental variables such as surface temperature, root zone soil moisture, and elevation, in relation to parasitic weed distribution and environmental conditions over time, in combination with observational data from the Global Biodiversity Information Facility (GBIF). Our analysis reveals contrasting environmental and altitude preferences in the genera Striga and Orobanche. Asiatic witchweed (Striga asiatica), which infests corn, rice, sorghum, and sugar cane crops, appears to be expanding its range in high elevation habitats. It also shows a significant association with heat‐moisture coupling events, the frequency of which is rising in such environments. These results point to geographical shifts in distribution and abundance in parasitic weeds due to climate change.

Rautela, K., A. Kumar, S. K. Rana, A. Jugran, and I. D. Bhatt. 2024. Distribution, Chemical Constituents and Biological Properties of Genus Malaxis. Chemistry & Biodiversity.

The genus Malaxis (family Orchidaceae), comprises nearly 183 species available across the globe. The plants of this genus have long been employed in traditional medical practices because of their numerous biological properties, like the treatment of infertility, hemostasis, burning sensation, bleeding diathesis, fever, diarrhea, dysentery, febrifuge, tuberculosis, etc. Various reports highlight their phytochemical composition and biological activities. However, there is a lack of systematic review on the distribution, phytochemistry, and biological properties of this genus. Hence, this study aims to conduct a thorough and critical review of Malaxis species, covering data published from 1965 to 2022 with nearly 90 articles. Also, it examines different bioactive compounds, their chemistry, and pharmacotherapeutics as well as their traditional uses. A total of 191 unique compounds, including the oil constituents were recorded from Malaxis species. The highest active ingredients were obtained from Malaxis acuminata (103) followed by Malaxis muscifera (50) and Malaxis rheedei (33). In conclusion, this review offers an overview of the current state of knowledge on Malaxis species and highlights prospects for future research projects on them. Additionally, it recommends the promotion of domestication studies for rare medicinal orchids like Malaxis and the prompt implementation of conservation measures.

Noori, S., A. Hofmann, D. Rödder, M. Husemann, and H. Rajaei. 2024. A window to the future: effects of climate change on the distribution patterns of Iranian Zygaenidae and their host plants. Biodiversity and Conservation.

Climate change has been suggested as an important human-induced driver for the ongoing sixth mass extinction. As a common response to climate change, and particularly global warming, species move toward higher latitudes or shift uphill. Furthermore, rapid climate change impacts the biotic interactions of species, particularly in the case of Zygaenid moths which exhibit high specialization in both habitat and host plant preferences. Iranian Zygaenidae are relatively well-known and represent a unique fauna with a high endemism rate (46%) in the whole Palearctic; as such they are a good model group to study the impact of climate change on future distributions. In this study, we used species distribution models (SDMs) and ensembles of small models (ESMs) to investigate the impact of climate change on the future distribution of endemic and non-endemic species of zygaenids, as well as their larval host plants. Three different climate scenarios were applied to forecast the probable responses of the species to different climate change intensities. Our results suggest that the central and southern parts of the country will be impacted profoundly by climate change compared to the northern regions. Beyond this, most endemic species will experience an altitudinal shift from their current range, while non-endemic species may move towards higher latitudes. Considering that the regions with higher diversity of zygaenids are limited to mountainous areas, mainly within the Irano-Anatolian biodiversity hotspot, the identification of their local high diversity regions for conservation practices has a high priority.

Weiss, R. M., F. Zanetti, B. Alberghini, D. Puttick, M. A. Vankosky, A. Monti, and C. Eynck. 2024. Bioclimatic analysis of potential worldwide production of spring‐type camelina [Camelina sativa (L.) Crantz] seeded in the spring. GCB Bioenergy 16.

Camelina [Camelina sativa (L.) Crantz] is a Brassicaceae oilseed that is gaining interest worldwide as low‐maintenance crop for diverse biobased applications. One of the most important factors determining its productivity is climate. We conducted a bioclimate analysis in order to analyze the relationship between climatic factors and the productivity of spring‐type camelina seeded in the spring, and to identify regions of the world with potential for camelina in this scenario. Using the modelling tool CLIMEX, a bioclimatic model was developed for spring‐seeded spring‐type camelina to match distribution, reported seed yields and phenology records in North America. Distribution, yield, and phenology data from outside of North America were used as independent datasets for model validation and demonstrated that model projections agreed with published distribution records, reported spring‐seeded camelina yields, and closely predicted crop phenology in Europe, South America, and Asia. Sensitivity analysis, used to quantify the response of camelina to changes in precipitation and temperature, indicated that crop performance was more sensitive to moisture than temperature index parameters, suggesting that the yield potential of spring‐seeded camelina may be more strongly impacted by water‐limited conditions than by high temperatures. Incremental climate scenarios also revealed that spring‐seeded camelina production will exhibit yield shifts at the continental scale as temperature and precipitation deviate from current conditions. Yield data were compared with indices of climatic suitability to provide estimates of potential worldwide camelina productivity. This information was used to identify new areas where spring‐seeded camelina could be grown and areas that may permit expanded production, including eastern Europe, China, eastern Russia, Australia and New Zealand. Our model is the first to have taken a systematic approach to determine suitable regions for potential worldwide production of spring‐seeded camelina.

Qin, F., T. Xue, X. Zhang, X. Yang, J. Yu, S. R. Gadagkar, and S. Yu. 2023. Past climate cooling and orogenesis of the Hengduan Mountains have influenced the evolution of Impatiens sect. Impatiens (Balsaminaceae) in the Northern Hemisphere. BMC Plant Biology 23.

Background Impatiens sect. Impatiens is distributed across the Northern Hemisphere and has diversified considerably, particularly within the Hengduan Mountains (HDM) in southwest China. Yet, the infra-sectional phylogenetic relationships are not well resolved, largely due to limited taxon sampling and an insufficient number of molecular markers. The evolutionary history of its diversification is also poorly understood. In this study, plastome data and the most complete sampling to date were used to reconstruct a robust phylogenetic framework for this section. The phylogeny was then used to investigate its biogeographical history and diversification patterns, specifically with the aim of understanding the role played by the HDM and past climatic changes in its diversification. Results A stable phylogeny was reconstructed that strongly supported both the monophyly of the section and its division into seven major clades (Clades I-VII). Molecular dating and ancestral area reconstruction suggest that sect. Impatiens originated in the HDM and Southeast China around 11.76 Ma, after which different lineages dispersed to Northwest China, temperate Eurasia, and North America, mainly during the Pliocene and Pleistocene. An intercontinental dispersal event from East Asia to western North America may have occurred via the Bering Land Bridge or Aleutian Islands. The diversification rate was high during its early history, especially with the HDM, but gradually decreased over time both within and outside the HDM. Multiple linear regression analysis showed that the distribution pattern of species richness was strongly associated with elevation range, elevation, and mean annual temperature. Finally, ancestral niche analysis indicated that sect. Impatiens originated in a relatively cool, middle-elevation area. Conclusions We inferred the evolutionary history of sect. Impatiens based on a solid phylogenetic framework. The HDM was the primary source or pump of its diversity in the Northern Hemisphere. Orogeny and climate change may have also shaped its diversification rates, as a steady decrease in the diversification rate coincided with the uplift of the HDM and climate cooling. These findings provide insights into the distribution pattern of sect. Impatiens and other plants in the Northern Hemisphere.

Zhang, H., W. Guo, and W. Wang. 2023. The dimensionality reductions of environmental variables have a significant effect on the performance of species distribution models. Ecology and Evolution 13.

How to effectively obtain species‐related low‐dimensional data from massive environmental variables has become an urgent problem for species distribution models (SDMs). In this study, we will explore whether dimensionality reduction on environmental variables can improve the predictive performance of SDMs. We first used two linear (i.e., principal component analysis (PCA) and independent components analysis) and two nonlinear (i.e., kernel principal component analysis (KPCA) and uniform manifold approximation and projection) dimensionality reduction techniques (DRTs) to reduce the dimensionality of high‐dimensional environmental data. Then, we established five SDMs based on the environmental variables of dimensionality reduction for 23 real plant species and nine virtual species, and compared the predictive performance of those with the SDMs based on the selected environmental variables through Pearson's correlation coefficient (PCC). In addition, we studied the effects of DRTs, model complexity, and sample size on the predictive performance of SDMs. The predictive performance of SDMs under DRTs other than KPCA is better than using PCC. And the predictive performance of SDMs using linear DRTs is better than using nonlinear DRTs. In addition, using DRTs to deal with environmental variables has no less impact on the predictive performance of SDMs than model complexity and sample size. When the model complexity is at the complex level, PCA can improve the predictive performance of SDMs the most by 2.55% compared with PCC. At the middle level of sample size, the PCA improved the predictive performance of SDMs by 2.68% compared with the PCC. Our study demonstrates that DRTs have a significant effect on the predictive performance of SDMs. Specifically, linear DRTs, especially PCA, are more effective at improving model predictive performance under relatively complex model complexity or large sample sizes.

Yim, C., E. S. Bellis, V. L. DeLeo, D. Gamba, R. Muscarella, and J. R. Lasky. 2023. Climate biogeography of Arabidopsis thaliana: Linking distribution models and individual variation. Journal of Biogeography.

Aim Patterns of individual variation are key to testing hypotheses about the mechanisms underlying biogeographic patterns. If species distributions are determined by environmental constraints, then populations near range margins may have reduced performance and be adapted to harsher environments. Model organisms are potentially important systems for biogeographical studies, given the available range‐wide natural history collections, and the importance of providing biogeographical context to their genetic and phenotypic diversity.LocationGlobal.TaxonArabidopsis thaliana (‘Arabidopsis’).MethodsWe fit occurrence records to climate data, and then projected the distribution of Arabidopsis under last glacial maximum, current and future climates. We confronted model predictions with individual performance measured on 2194 herbarium specimens, and we asked whether predicted suitability was associated with life history and genomic variation measured on ~900 natural accessions.ResultsThe most important climate variables constraining the Arabidopsis distribution were winter cold in northern and high elevation regions and summer heat in southern regions. Herbarium specimens from regions with lower habitat suitability in both northern and southern regions were smaller, supporting the hypothesis that the distribution of Arabidopsis is constrained by climate‐associated factors. Climate anomalies partly explained interannual variation in herbarium specimen size, but these did not closely correspond to local limiting factors identified in the distribution model. Late‐flowering genotypes were absent from the lowest suitability regions, suggesting slower life histories are only viable closer to the centre of the realized niche. We identified glacial refugia farther north than previously recognized, as well as refugia concordant with previous population genetic findings. Lower latitude populations, known to be genetically distinct, are most threatened by future climate change. The recently colonized range of Arabidopsis was well‐predicted by our native‐range model applied to certain regions but not others, suggesting it has colonized novel climates.Main ConclusionsIntegration of distribution models with performance data from vast natural history collections is a route forward for testing biogeographical hypotheses about species distributions and their relationship with evolutionary fitness across large scales.

Rodríguez-Merino, A. 2023. Identifying and Managing Areas under Threat in the Iberian Peninsula: An Invasion Risk Atlas for Non-Native Aquatic Plant Species as a Potential Tool. Plants 12: 3069.

Predicting the likelihood that non-native species will be introduced into new areas remains one of conservation’s greatest challenges and, consequently, it is necessary to adopt adequate management measures to mitigate the effects of future biological invasions. At present, not much information is available on the areas in which non-native aquatic plant species could establish themselves in the Iberian Peninsula. Species distribution models were used to predict the potential invasion risk of (1) non-native aquatic plant species already established in the peninsula (32 species) and (2) those with the potential to invade the peninsula (40 species). The results revealed that the Iberian Peninsula contains a number of areas capable of hosting non-native aquatic plant species. Areas under anthropogenic pressure are at the greatest risk of invasion, and the variable most related to invasion risk is temperature. The results of this work were used to create the Invasion Risk Atlas for Alien Aquatic Plants in the Iberian Peninsula, a novel online resource that provides information about the potential distribution of non-native aquatic plant species. The atlas and this article are intended to serve as reference tools for the development of public policies, management regimes, and control strategies aimed at the prevention, mitigation, and eradication of non-native aquatic plant species.

Nikkel, E., D. R. Clements, D. Anderson, and J. L. Williams. 2023. Regional habitat suitability for aquatic and terrestrial invasive plant species may expand or contract with climate change. Biological Invasions.

The threat of invasive species to biodiversity and ecosystem structure is exacerbated by the increasingly concerning outlook of predicted climate change and other human influences. Developing preventative management strategies for invasive plant species before they establish is crucial for effective management. To examine how climate change may impact habitat suitability, we modeled the current and future habitat suitability of two terrestrial species, Geranium lucidum and Pilosella officinarum , and two aquatic species, Butomus umbellatus and Pontederia crassipes , that are relatively new invasive plant species regionally, and are currently spreading in the Pacific Northwest (PNW, North America), an area of unique natural areas, vibrant economic activity, and increasing human population. Using North American presence records, downscaled climate variables, and human influence data, we developed an ensemble model of six algorithms to predict the potential habitat suitability under current conditions and projected climate scenarios RCP 4.5, 7.0, and 8.5 for 2050 and 2080. One terrestrial species ( P. officinarum ) showed declining habitat suitability in future climate scenarios (contracted distribution), while the other terrestrial species ( G. lucidum ) showed increased suitability over much of the region (expanded distribution overall). The two aquatic species were predicted to have only moderately increased suitability, suggesting aquatic plant species may be less impacted by climate change. Our research provides a template for regional-scale modelling of invasive species of concern, thus assisting local land managers and practitioners to inform current and future management strategies and to prioritize limited available resources for species with expanding ranges.

Benson, C. W., M. R. Sheltra, P. J. Maughan, E. N. Jellen, M. D. Robbins, B. S. Bushman, E. L. Patterson, et al. 2023. Homoeologous evolution of the allotetraploid genome of Poa annua L. BMC Genomics 24.

Background Poa annua (annual bluegrass) is an allotetraploid turfgrass, an agronomically significant weed, and one of the most widely dispersed plant species on earth. Here, we report the chromosome-scale genome assemblies of P. annua’s diploid progenitors, P. infirma and P. supina, and use multi-omic analyses spanning all three species to better understand P. annua’s evolutionary novelty. Results We find that the diploids diverged from their common ancestor 5.5 – 6.3 million years ago and hybridized to form P. annua  ≤ 50,000 years ago. The diploid genomes are similar in chromosome structure and most notably distinguished by the divergent evolutionary histories of their transposable elements, leading to a 1.7 × difference in genome size. In allotetraploid P. annua, we find biased movement of retrotransposons from the larger (A) subgenome to the smaller (B) subgenome. We show that P. annua’s B subgenome is preferentially accumulating genes and that its genes are more highly expressed. Whole-genome resequencing of several additional P. annua accessions revealed large-scale chromosomal rearrangements characterized by extensive TE-downsizing and evidence to support the Genome Balance Hypothesis. Conclusions The divergent evolutions of the diploid progenitors played a central role in conferring onto P. annua its remarkable phenotypic plasticity. We find that plant genes (guided by selection and drift) and transposable elements (mostly guided by host immunity) each respond to polyploidy in unique ways and that P. annua uses whole-genome duplication to purge highly parasitized heterochromatic sequences. The findings and genomic resources presented here will enable the development of homoeolog-specific markers for accelerated weed science and turfgrass breeding .