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Frontiers in Microbiology 2022While investigating the bacterial populations of environmental samples taken from a mix of healthy and Acute Oak Decline afflicted (pedunculate or English oak)...
While investigating the bacterial populations of environmental samples taken from a mix of healthy and Acute Oak Decline afflicted (pedunculate or English oak) rhizosphere soil samples and swabs of bleeding lesions on spp. (lime) and (red oak) trees, several strains belonging to the order were isolated using selective media and enrichment broth. Seven strains from the rhizosphere, three strains from spp. and one from were investigated, with their taxonomic status determined a polyphasic taxonomic approach. Initially stains were identified as potential members of the recently described genus , based on the partial sequencing of three housekeeping genes. Further analysis of phenotypic traits, including fatty acid profiles, coupled with 16S rRNA gene and phylogenomic analysis of whole genome sequences were applied to a subset of the strains. Phylogenetic and phylogenomic analysis repeatedly placed the isolates in a monophyletic clade within , with four distinct clusters observed, one of which corresponded to , the type species of the genus. The remaining three clusters could be phenotypically and genotypically differentiated from each other and As such, we describe three novel species of the genus, for which we propose the names sp. nov. (type strain H11S7 = LMG 32612 = CCUG 76179), sp. nov. (type strain H17S15 = LMG 32613 = CCUG 76183) and sp. nov. (type strain TWS1a = LMG 32614 = CCUG 76188). Additionally, the descriptions of the genus and the type species, , are emended.
PubMed: 36304948
DOI: 10.3389/fmicb.2022.1011653 -
Plant Physiology Nov 2022Drought and waterlogging impede tree growth and may even lead to tree death. Oaks, an emblematic group of tree species, have evolved a range of adaptations to cope with...
Drought and waterlogging impede tree growth and may even lead to tree death. Oaks, an emblematic group of tree species, have evolved a range of adaptations to cope with these constraints. The two most widely distributed European species, pedunculate (PO; Quercus robur L.) and sessile oak (SO; Quercus petraea Matt. Lieb), have overlapping ranges, but their respective distribution are highly constrained by local soil conditions. These contrasting ecological preferences between two closely related and frequently hybridizing species constitute a powerful model to explore the functional bases of the adaptive responses in oak. We exposed oak seedlings to waterlogging and drought, conditions typically encountered by the two species in their respective habitats, and studied changes in gene expression in roots using RNA-seq. We identified genes that change in expression between treatments differentially depending on species. These "species × environment"-responsive genes revealed adaptive molecular strategies involving adventitious and lateral root formation, aerenchyma formation in PO, and osmoregulation and ABA regulation in SO. With this experimental design, we also identified genes with different expression between species independently of water conditions imposed. Surprisingly, this category included genes with functions consistent with a role in intrinsic reproductive barriers. Finally, we compared our findings with those for a genome scan of species divergence and found that the expressional candidate genes included numerous highly differentiated genetic markers between the two species. By combining transcriptomic analysis, gene annotation, pathway analyses, as well as genome scan for genetic differentiation among species, we were able to highlight loci likely involved in adaptation of the two species to their respective ecological niches.
Topics: Quercus; Water; Soil; Trees; Gene Expression
PubMed: 36066428
DOI: 10.1093/plphys/kiac420 -
The Journal of Animal Ecology Nov 2022Climate change has been shown to advance spring phenology, increase the number of insect generations per year (multivoltinism) and increase pathogen infection levels....
Climate change has been shown to advance spring phenology, increase the number of insect generations per year (multivoltinism) and increase pathogen infection levels. However, we lack insights into the effects of plant spring phenology and the biotic environment on the preference and performance of multivoltine herbivores and whether such effects extend into the later part of the growing season. To this aim, we used a multifactorial growth chamber experiment to examine the influence of spring phenology on plant pathogen infection, and how the independent and interactive effects of spring phenology and plant pathogen infection affect the preference and performance of multigenerational attackers (the leaf miner Tischeria ekebladella and the aphid Tuberculatus annulatus) on the pedunculate oak in the early, mid and late parts of the plant growing season. Pathogen infection was highest on late phenology plants, irrespective of whether inoculations were conducted in the early, mid or late season. The leaf miner consistently preferred to oviposit on middle and late phenology plants, as well as healthy plants, during all parts of the growing season, whereas we detected an interactive effect between spring phenology and pathogen infection on the performance of the leaf miner. Aphids preferred healthy, late phenology plants during the early season, healthy plants during the mid season, and middle phenology plants during the late season, whereas aphid performance was consistently higher on healthy plants during all parts of the growing season. Our findings highlight that the impact of spring phenology on pathogen infection and the preference and performance of insect herbivores is not restricted to the early season, but that its imprint is still present - and sometimes equally strong - during the peak and end of the growing season. Plant pathogens generally negatively affected herbivore preference and performance, and modulated the effects of spring phenology. We conclude that spring phenology and pathogen infection are two important factors shaping the preference and performance of multigenerational plant attackers, which is particularly relevant given the current advance in spring phenology, pathogen outbreaks and increase in voltinism with climate change.
Topics: Animals; Seasons; Herbivory; Quercus; Plants; Insecta; Climate Change; Aphids; Temperature; Plant Leaves
PubMed: 36047365
DOI: 10.1111/1365-2656.13804 -
Metabolites Aug 2022Pedunculate oak ( L.) is an economically important forest-forming species in Poland that produces seeds that are sensitive to desiccation; therefore, short-lived seeds...
Deterioration in the Quality of Recalcitrant Seeds during Six Months of Storage at Subzero Temperatures: Ineffective Activation of Prosurvival Mechanisms and Evidence of Freezing Stress from an Untargeted Metabolomic Study.
Pedunculate oak ( L.) is an economically important forest-forming species in Poland that produces seeds that are sensitive to desiccation; therefore, short-lived seeds are classified as recalcitrant. Such seeds display active metabolism throughout storage. Acorns stored under controlled conditions (moisture content of 40%, temperature -3 °C) maintain viability for up to 1.5-2 years. Meanwhile, oaks only produce large numbers of seeds every few years during so-called mast years. This results in a scarcity of good-quality seeds for continuous nursery production and restoration. The recalcitrant storage behavior and the requirements of foresters make it necessary to develop a new protocol for longer acorn storage at lower temperatures. Two storage temperatures were tested: -3 °C (currently used in forest practice) and -7 °C. Our results showed that acorns stored for six months exhibited deterioration and reduced germination capacity, as well as reduced seedling performance, particularly when acorns were stored at -7 °C. To elucidate the decrease in quality during storage, an untargeted metabolomics study was performed for the first time and supported with the analysis of carbohydrates and percentages of carbon (C) and nitrogen (N). Embryonic axes were characterized by a lower C:N ratio and higher hydration. A total of 1985 metabolites were detected, and 303 were successfully identified and quantified, revealing 44 known metabolites that displayed significantly up- or downregulated abundance. We demonstrated for the first time that the significant deterioration of seed germination potential, particularly in seeds stored at -7 °C, was accompanied by an increased abundance of phenolic compounds and carbohydrates but also amino acids and phosphorylated monosaccharides, particularly in the embryonic axes. The increased abundance of defense-related metabolites (1,2,4-Benzenetriol; BTO), products of ascorbic acid degradation (threonic and isothreonic acid), as well as antifreezing compounds (sugar alcohols, predominantly threitol), was reported in seed stored at -7 °C. We hypothesize that seed deterioration was caused by freezing stress experienced during six months of storage at -7 °C, a decline in antioxidative potential and the unsuccessful rerouting of the energy-production pathways. Additionally, our data are a good example of the application of high-throughput metabolomic tools in forest management.
PubMed: 36005628
DOI: 10.3390/metabo12080756 -
Frontiers in Plant Science 2022Plants interact with a multitude of microorganisms and insects, both below- and above ground, which might influence plant metabolism. Despite this, we lack knowledge of...
Plants interact with a multitude of microorganisms and insects, both below- and above ground, which might influence plant metabolism. Despite this, we lack knowledge of the impact of natural soil communities and multiple aboveground attackers on the metabolic responses of plants, and whether plant metabolic responses to single attack can predict responses to dual attack. We used untargeted metabolic fingerprinting (gas chromatography-mass spectrometry, GC-MS) on leaves of the pedunculate oak, , to assess the metabolic response to different soil microbiomes and aboveground single and dual attack by oak powdery mildew () and the common oak aphid (). Distinct soil microbiomes were not associated with differences in the metabolic profile of oak seedling leaves. Single attacks by aphids or mildew had pronounced but different effects on the oak leaf metabolome, but we detected no difference between the metabolomes of healthy seedlings and seedlings attacked by both aphids and powdery mildew. Our findings show that aboveground attackers can have species-specific and non-additive effects on the leaf metabolome of oak. The lack of a metabolic signature detected by GC-MS upon dual attack might suggest the existence of a potential negative feedback, and highlights the importance of considering the impacts of multiple attackers to gain mechanistic insights into the ecology and evolution of species interactions and the structure of plant-associated communities, as well as for the development of sustainable strategies to control agricultural pests and diseases and plant breeding.
PubMed: 35991442
DOI: 10.3389/fpls.2022.897186 -
Adapting a allometric equation to quantify carbon sequestration rates on the Middle Elbe floodplain.MethodsX 2022Destructively sampling old Pedunculate oak () trees on the active floodplain of the Middle Elbe to create an allometric equation to estimate carbon stocks (CS) and...
Destructively sampling old Pedunculate oak () trees on the active floodplain of the Middle Elbe to create an allometric equation to estimate carbon stocks (CS) and carbon sequestration rates (CSR) would defeat the purpose of protecting increasingly vulnerable and threatened primeval floodplain forests. To nondestructively estimate CS and CSR, we have adapted a two-parameter allometric equation which uses tree height (H) and diameter at breast height (DBH) (Dik 1984, Zianis et al. 2005) into a 1-parameter equation that requires only DBH to quantify stocks and annual changes in carbon stock (carbon sequestration rates) for individual trees. The equations have also been adapted to estimate below- and above-ground carbon stocks of individual trees. The new method has:•Adapted a 2-parameter allometric equation which estimates tree volume to a 1-parameter equation which estimates above and below-ground carbon stock•Removed the requirement of tree height to reconstruct the carbon stock of trees at an annual timestep•An almost perfect linear relationship (Pearson R= 0.998) between carbon sequestration rate and basal area increment (BAI).
PubMed: 35958097
DOI: 10.1016/j.mex.2022.101800 -
Cureus Jun 2022Natal teeth are teeth present at birth and are a rare finding. They most commonly occur in the mandibular incisor region and are thought to occur as an accelerated...
Natal teeth are teeth present at birth and are a rare finding. They most commonly occur in the mandibular incisor region and are thought to occur as an accelerated premature growth of normal primary teeth. They may present in the varying stages of tooth eruption and rarely on a pedunculated stalk of alveolar mucosa as described in this case. Natal teeth may be surgically extracted if difficulty feeding or ventral tongue ulceration develops. This report presents the case of an unusual pedunculated natal tooth in a newborn at a community hospital and describes its surgical management.
PubMed: 35859971
DOI: 10.7759/cureus.25992 -
The New Phytologist Aug 2022Many plant species produce multiple leaf flushes during the growing season, which might have major consequences for within-plant variation in chemistry and species...
Many plant species produce multiple leaf flushes during the growing season, which might have major consequences for within-plant variation in chemistry and species interactions. Yet, we lack a theoretical or empirical framework for how differences among leaf flushes might shape variation in damage by insects and diseases. We assessed the impact of leaf flush identity on leaf chemistry, insect attack and pathogen infection on the pedunculate oak Quercus robur by sampling leaves from each leaf flush in 20 populations across seven European countries during an entire growing season. The first leaf flush had higher levels of primary compounds, and lower levels of secondary compounds, than the second flush, whereas plant chemistry was highly variable in the third flush. Insect attack decreased from the first to the third flush, whereas infection by oak powdery mildew was lowest on leaves from the first flush. The relationship between plant chemistry, insect attack and pathogen infection varied strongly among leaf flushes and seasons. Our findings demonstrate the importance of considering differences among leaf flushes for our understanding of within-tree variation in chemistry, insect attack and disease levels, something particularly relevant given the expected increase in the number of leaf flushes with climate change.
Topics: Animals; Insecta; Plant Leaves; Quercus; Seasons; Trees
PubMed: 35514157
DOI: 10.1111/nph.18209 -
Ecology and Evolution Mar 2022Urbanization is an important driver of the diversity and abundance of tree-associated insect herbivores, but its consequences for insect herbivory are poorly understood....
Urbanization is an important driver of the diversity and abundance of tree-associated insect herbivores, but its consequences for insect herbivory are poorly understood. A likely source of variability among studies is the insufficient consideration of intra-urban variability in forest cover. With the help of citizen scientists, we investigated the independent and interactive effects of local canopy cover and percentage of impervious surface on insect herbivory in the pedunculate oak ( L.) throughout most of its geographic range in Europe. We found that the damage caused by chewing insect herbivores as well as the incidence of leaf-mining and gall-inducing herbivores consistently decreased with increasing impervious surface around focal oaks. Herbivory by chewing herbivores increased with increasing forest cover, regardless of impervious surface. In contrast, an increase in local canopy cover buffered the negative effect of impervious surface on leaf miners and strengthened its effect on gall inducers. These results show that-just like in non-urban areas-plant-herbivore interactions in cities are structured by a complex set of interacting factors. This highlights that local habitat characteristics within cities have the potential to attenuate or modify the effect of impervious surfaces on biotic interactions.
PubMed: 35342614
DOI: 10.1002/ece3.8709 -
Endoscopy Nov 2022
Topics: Humans; Esophageal Neoplasms; Endoscopy; Endoscopy, Gastrointestinal; Ligation
PubMed: 35168273
DOI: 10.1055/a-1662-3738