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Societal Impact Statement Palms provide vital plant resources and ecosystem services to people across the tropics. To improve conservation guidance, a “health check” of palms in two highly threatened biodiversity hotspots in Colombia and Ecuador was undertaken. Palms are very diverse in these regions, but over one third are threatened with extinction now, especially among endemic species. Widespread and useful palms are also under intense human pressure and need to be prioritized in terms of sustainable management practices. Given the importance of palms for humans, inclusive conservation actions should be continued in both countries in order to safeguard this resource. Summary Palms provide central plant resources to societies in the tropics, especially in the Global South. The western Pacific and Andean regions of Colombia and Ecuador host two hotspots of biodiversity. To prioritize conservation policies towards palms, we undertook a conservation assessment of species in the region. We compiled a taxonomically verified database of specimens collected in both hotspots. We inferred preliminary conservation assessments using International Union for Conservation of Nature (IUCN) Criteria B. In addition, we evaluated the level of exposure of palms to human use and population density using the anthrome concept. We documented 144 native palm species in 33 genera occurring in both hotspots of Colombia and Ecuador. Of these, 55 are endemic to this region. We recorded 133 species for Colombia, 43 endemic, and 71 species for Ecuador, 9 endemic. A third of all palm species in the region are potentially threatened with extinction (50/144) and 12 as preliminary Critically Endangered. Aiphanes and Geonoma have the highest number of threatened species. In total, 60% of palm specimens were collected in the “low human impact” anthrome type. In contrast, 41% of specimens occur in high human density areas. The two hotspots of biodiversity in Colombia and Ecuador are very diverse in palms. However, we show that this diversity is under threat and is predominantly found in areas impacted by human activities. Extinction risk is highest in endemic species in both countries. Widespread and useful palm species also face threats linked to overexploitation or habitat loss. Inclusive conservation measures should be designed to conserve, together with communities, this plant resource.

Abstract Conservation and sustainable management of lineages providing non‐timber forest products are imperative under the current global biodiversity loss. Most non‐timber forest species, however, lack genomic studies that characterize their intraspecific variation and evolutionary history, which inform species' conservation practices. Contrary to many lineages in the Andean biodiversity hotspot that exhibit high diversification, the genus Parajubaea (Arecaceae) has only three species despite the genus' origin 22 million years ago. Two of the three palm species, P. torallyi and P. sunkha, are non‐timber forest species endemic to the Andes of Bolivia and are listed as IUCN endangered. The third species, P. cocoides, is a vulnerable species with unknown wild populations. We investigated the evolutionary relationships of Parajubaea species and the genetic diversity and structure of wild Bolivian populations. Sequencing of five low‐copy nuclear genes (3753 bp) challenged the hypothesis that P. cocoides is a cultigen that originated from the wild Bolivian species. We further obtained up to 15,134 de novo single‐nucleotide polymorphism markers by genotyping‐by‐sequencing of 194 wild Parajubaea individuals. Our total DNA sequencing effort rejected the taxonomic separation of the two Bolivian species. As expected for narrow endemic species, we observed low genetic diversity, but no inbreeding signal. We found three genetic clusters shaped by geographic distance, which we use to propose three management units. Different percentages of missing genotypic data did not impact the genetic structure of populations. We use the management units to recommend in situ conservation by creating new protected areas, and ex situ conservation through seed collection.

Abstract Hybridization has significant evolutionary consequences across the Tree of Life. The process of hybridization has played a major role in plant evolution and has contributed to species richness and trait variation. Since morphological traits are partially a product of their environment, there may be a link between hybridization and ecology. Plant hybrid species richness is noted to be higher in harsh environments, and we explore this hypothesis with a keystone tropical plant lineage, palms (Arecaceae). Leveraging a recent literature review of naturally occurring palm hybrids, we developed a method to calculate hybrid frequency, and then tested if there is phylogenetic signal of hybrids using a phylogeny of all palms. Further, we used phylogenetic comparative methods to examine the interaction between hybrid frequency and presence in dry environments, on islands, and the species richness of genera. Phylogenetic generalized least squares models had stronger support than models of random association, indicating phylogenetic signal for the presence of hybrids in dry and island environments. However, all p‐values were >.05 and therefore the correlation was poor between hybridization and the trait frequencies examined. Presence in particular environments are not strongly correlated to hybrid frequency, but phylogenetic signal suggests a role in its distribution in different habitats. Hybridization in palms is not evenly distributed across subfamilies, tribes, subtribes yet plays an important role in palm diversity, nonetheless. Increasing our understanding hybridization in this economically and culturally important plant family is essential, particularly since rates are projected to increase with climate change, reconfiguring the dynamics and distribution of biodiversity.

Abstract Discoid lupus erythematosus is an autoimmune connective‐tissue disease that represents a subset of conditions on the cutaneous lupus spectrum. The lesions are characterized by disk‐shaped plaques on photo‐exposed skin with inflammatory hyperpigmentation and adherent scale. Here, we present a patient with a rare manifestation of discoid lesions on the palms.

Abstract In accordance with Article 6 of Regulation (EC) No 396/2005, the applicant Syngenta Crop Protection AG submitted a request to the competent national authority in Belgium to set an import tolerance for the active substance metalaxyl‐M in oil palms fruits and peppercorn (black, green and white). The data submitted in support of the request were found to be sufficient to derive MRL proposals for oil palms fruits and peppercorn. Adequate analytical methods for enforcement are available to control the residues of metalaxyl‐M in the commodities under consideration at the validated limit of quantification (LOQ) of 0.01 mg/kg. Based on the risk assessment results, EFSA concluded that the short‐term and long‐term intake of residues resulting from the use of metalaxyl‐M according to the authorised agricultural practices is unlikely to present a risk to consumer health.

Abstract In accordance with Article 6 of Regulation (EC) No 396/2005, the applicant FMC Agro Ltd submitted a request to the competent national authority in the United Kingdom to set import tolerances for the active substance chlorantraniliprole in oil palms fruits and oil palms kernels. The data submitted in support of the request were found to be sufficient to derive maximum residue level (MRL) proposals for these products. Adequate analytical methods for enforcement are available to control the residues of chlorantraniliprole in the commodities under consideration at the validated limit of quantification (LOQ) of 0.01 mg/kg. Based on the risk assessment results, EFSA concluded that the long‐term intake of residues resulting from the use of chlorantraniliprole according to the reported agricultural practice is unlikely to present a risk to consumer health.

Premise: Life span varies greatly across plants, with some species being capable of extreme longevity. Yet even long-lived individuals are susceptible to climatic events, fire, and other challenges. We examined rare mortality events and their causes in two long-lived palmettos over four decades., Methods: We monitored the survival of the clonal Serenoa repens and non-clonal, Florida-endemic Sabal etonia from 1981 to 2022 in four habitats along an elevational gradient within the globally imperiled Florida scrub ecosystem. We considered several challenges to palmetto survival, including extreme fires, shading due to lack of fire, droughts, periods of high precipitation, and possible pathogens., Results: Survival of palmettos was remarkably high, and mortality was infrequent (Serenoa: cumulative, 5.7%; annualized, 0%-0.68%; Sabal: cumulative, 3.5%; annualized, 0%-0.43%). Mortality was highest in higher-elevation habitats with greater soil drainage, and smaller palmettos were more likely to die. When subjected to extreme fire, Serenoa suffered greater mortality than Sabal. Mortality in long-unburned habitats with increased shading rivaled that which occurred with extreme fire. There was no evidence of mortality due to lethal bronzing palm disease., Conclusions: Both palmettos had exceptionally low mortality rates, which, coupled with earlier work showing slow rates of transition from seedling to adult and remarkable adult longevity, suggest notably low rates of population turnover. Observed mortality in long-unburned habitats suggests the importance of fire-management planning with prescription burning. Lengthy age to reproduction and/or dependency on clonal propagation limits migration or genetic adaptation to altered conditions caused by climate change., (© 2023 The Authors. American Journal of Botany published by Wiley Periodicals LLC on behalf of Botanical Society of America.)

Abstract Isoprene synthase (IspS) is the sole enzyme in plants responsible for the yearly emission in the atmosphere of thousands of tonnes of the natural hydrocarbon isoprene worldwide. Species of the monocotyledonous family Arecaceae (palms) are among the highest plant emitters, but to date no IspS gene from this family has been identified. Here, we screened with PTR‐ToF‐MS 18 genera of the Arecaceae for isoprene emission and found that the majority of the sampled species emits isoprene. Putative IspS genes from six different genera were sequenced and three of them were functionally characterized by heterologous overexpression in Arabidopsis thaliana, demonstrating that they encode functional IspS genes. Site‐directed mutagenesis and expression in Arabidopsis demonstrated the functional relevance of a novel IspS diagnostic tetrad from Arecaceae, whose most variable amino acids could not preserve catalytic function when substituted by a putatively dicotyledonous‐specific tetrad. In particular, mutation of threonine 479 likely impairs the open–closed transition of the enzyme by altering the network of hydrogen bonds between helices H1α, H, and I. These results shed new light on the evolution of IspS in monocots, suggesting that isoprene emission is an ancestral trait within the Arecaceae family. The identification of IspS from Arecaceae provides promising novel enzymes for the production of isoprene in heterologous systems and allows the screening and selection of commercially relevant palm varieties with lower environmental impact.

Abstract Crop diversity is shaped by biological and social processes interacting at different spatiotemporal scales. Here, we combined population genetics and ethnobotany to investigate date palm (Phoenix dactylifera L.) diversity in Siwa Oasis, Egypt. Based on interviews with farmers and observation of practices in the field, we collected 149 date palms from Siwa Oasis and 27 uncultivated date palms from abandoned oases in the surrounding desert. Using genotyping data from 18 nuclear and plastid microsatellite loci, we confirmed that some named types each constitute a clonal line, that is, a true‐to‐type cultivar. We also found that others are collections of clonal lines, that is, ethnovarieties, or even unrelated samples, that is, local categories. This alters current assessments of agrobiodiversity, which are visibly underestimated, and uncovers the impact of low‐intensity, but highly effective, farming practices on biodiversity. These hardly observable practices, hypothesized by ethnographic survey and confirmed by genetic analysis, are enabled by the way Isiwans conceive and classify living beings in their oasis, which do not quite match the way biologists do: a classic disparity of etic versus. emic categorizations. In addition, we established that Siwa date palms represent a unique and highly diverse genetic cluster, rather than a subset of North African and Middle Eastern palm diversity. As previously shown, North African date palms display evidence of introgression by the wild relative Phoenix theophrasti, and we found that the uncultivated date palms from the abandoned oases share even more alleles with this species than cultivated palms in this region. The study of Siwa date palms could hence be a key to the understanding of date palm diversification in North Africa. Integration of ethnography and population genetics promoted the understanding of the interplay between diversity management in the oasis (short‐time scale), and the origins and dynamic of diversity through domestication and diversification (long‐time scale).