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Pine Wilt Disease (PWD) is a devastating pine tree disease characterized by rapid onset, high mortality rate, quick spread, and difficulty in control. Plant microbiome plays a significant role in the development of PWD. However, the endophytic microbial communities of Pinus koraiensis infected by pine wood nematode (PWN) Bursaphelenchus xylophilus remain largely unexplored. In this study, we analyzed the structural changes of endophytic communities of P. koraiensis after infection by the PWN using high-throughput sequencing technology. The results showed that the community structure underwent significant changes as the degree of PWN infection intensified. The diversity and abundance of endophytic fungi in P. koraiensis increased, while those of endophytic bacteria in P. koraiensis decreased during the infection process. Meanwhile, the abundance of some dominant microorganisms has also changed, including species such as Graphilbum and Pseudoalteromonas. Functional prediction analysis showed that the functional composition of endophytic fungi in P. koraiensis was significantly different across the development of PWD, while the composition of endophytic bacteria remained essentially similar. The results indicated that PWN infection had a significant impact on the structure, diversity, abundance, and functional gene composition of endophytic microbial communities in P. koraiensis , and most of the main endophytic microbial groups tended to coordinate with each other. This work provides a better understanding of the changes in endophytic community structure and function caused by PWD infection of P. koraiensis , which may benefit the exploration of potential endophytes for PWN biocontrol. [ABSTRACT FROM AUTHOR]

When products were marketed as "Canadian" in the early American press, it meant more than simply "Made in Canada." The author argues that "Canadian" served as a brand in early American advertising to denote the robust and hardy qualities of the product. Like Canada and its inhabitants, both of which were portrayed as rugged and raw, products labelled "Canadian" were marketed as similarly sturdy and tough, even if those products had not actually originated in Canada. As far as early American advertisers were concerned, "Canadian" products were unique, and it was beneficial to advertise that fact. [ABSTRACT FROM AUTHOR]

Pine Wilt Disease (PWD) is a devastating pine tree disease characterized by rapid onset, high mortality rate, quick spread, and difficulty in control. Plant microbiome plays a significant role in the development of PWD. However, the endophytic microbial communities of Pinus koraiensis infected by pine wood nematode (PWN) Bursaphelenchus xylophilus remain largely unexplored. In this study, we analyzed the structural changes of endophytic communities of P. koraiensis after infection by the PWN using high-throughput sequencing technology. The results showed that the community structure underwent significant changes as the degree of PWN infection intensified. The diversity and abundance of endophytic fungi in P. koraiensis increased, while those of endophytic bacteria in P. koraiensis decreased during the infection process. Meanwhile, the abundance of some dominant microorganisms has also changed, including species such as Graphilbum and Pseudoalteromonas. Functional prediction analysis showed that the functional composition of endophytic fungi in P. koraiensis was significantly different across the development of PWD, while the composition of endophytic bacteria remained essentially similar. The results indicated that PWN infection had a significant impact on the structure, diversity, abundance, and functional gene composition of endophytic microbial communities in P. koraiensis, and most of the main endophytic microbial groups tended to coordinate with each other. This work provides a better understanding of the changes in endophytic community structure and function caused by PWD infection of P. koraiensis, which may benefit the exploration of potential endophytes for PWN biocontrol.

This publication provides an in-depth profile of Pinus glabra for the use of interested laypersons with some knowledge of biology as well as the academic audiences.

SUMMARY: Scots pine (Pinus sylvestris L.) is one of the most widespread and economically important conifer species in the world. Applications like genomic selection and association studies, which could help accelerate breeding cycles, are challenging in Scots pine because of its large and repetitive genome. For this reason, genotyping tools for conifer species, and in particular for Scots pine, are commonly based on transcribed regions of the genome. In this article, we present the Axiom Psyl50K array, the first single nucleotide polymorphism (SNP) genotyping array for Scots pine based on whole‐genome resequencing, that represents both genic and intergenic regions. This array was designed following a two‐step procedure: first, 192 trees were sequenced, and a 430K SNP screening array was constructed. Then, 480 samples, including haploid megagametophytes, full‐sib family trios, breeding population, and range‐wide individuals from across Eurasia were genotyped with the screening array. The best 50K SNPs were selected based on quality, replicability, distribution across the draft genome assembly, balance between genic and intergenic regions, and genotype–environment and genotype–phenotype associations. Of the final 49 877 probes tiled in the array, 20 372 (40.84%) occur inside gene models, while the rest lie in intergenic regions. We also show that the Psyl50K array can yield enough high‐confidence SNPs for genetic studies in pine species from North America and Eurasia. This new genotyping tool will be a valuable resource for high‐throughput fundamental and applied research of Scots pine and other pine species. Significance Statement: In this paper, we present the first high‐throughput single nucleotide polymorphism genotyping array for a pine species developed from whole‐genome resequencing, and thus spanning genic as well as intergenic regions. This array was developed for Scots pine and successfully tested in six other pine species from North America and Eurasia, being useful for fundamental and applied studies in the fields of population genetics, evolution, genomic selection, and breeding. [ABSTRACT FROM AUTHOR]

The detection of invasive species is a crucial step for environmental management. However, traditional methods often require intensive labor in the field, which tends to be time-consuming and costly. In contrast, drones can cover large areas quickly and efficiently, creating a cost-effective alternative. However, the use of drones to detect or monitor invasive trees in coastal ecosystems is still unusual. For this reason, we carried out a trial to verify whether drones can effectively detect invasive alien pine trees at reduced costs in comparison with traditional detection methods. A drone was used to survey an area invaded by pines in an open coastal ecosystem in southern Brazil. We estimated total cost and time for detecting and controlling pines with and without the use of a drone. When using a drone to locate pines and conduct targeted control activities, the cost was reduced to approximately one-third compared with traditional methods. The time needed to detect and control invasive trees was more than seven times less compared with traditional active search and control. Our study demonstrates the potential of drone use for early detection, monitoring and control of invasive plant species in coastal and other open ecosystems. The use of drones can provide a cost-effective and efficient way to detect invasive plant species, allowing for targeted control actions. [ABSTRACT FROM AUTHOR]

Biological invasions are a widely known problem throughout the world, because of the damage they cause to the environment and biotic communities. In Argentina, many exotic woody species have been introduced by humans for ornamental or economic purposes, among them Pinus halepensis. This species has a high invasive potential, given its physiological plasticity and stress tolerance. Aims of this study were to determine the environmental variables that favored invasion of P. halepensis, and to assess the habitat suitability for the species throughout South America. For this, we used the maximum entropy algorithm (Maxent) and twenty one climatic variables from the WorldClim website. The significant predictive variables were the mean temperature of coldest quarter, annual precipitation, isothermality, precipitation of driest month, mean diurnal range, and the mean temperature of wettest quarter. The most suitable areas would correspond to the central-eastern region of Argentina, Uruguay and Central Chile. According to results, the high plasticity of the species, and considering the current discussion on climate change, which predicts an increase in severe droughts and extreme temperature events, an even more favorable environment for the invasion of P. halepensis is to be expected. [ABSTRACT FROM AUTHOR]

Sharon Shafer, Chair-Elect of NGCIG, launched the discussion by giving historical context to the third ever meeting of the Next Generation Catalog Interest Group. The first meeting of NGCIG addressed commercial alternatives to the traditional library catalog, the second meeting focused on non-commercial, open source endeavors while the third meeting was dedicated to next steps in next-generation catalogs. The meeting held presentations and discussion about two examples of recent next generation catalog endeavors. Karen Schneider (Evangelist for Equinox’s Evergreen support) shared what she does as an Evangelist by giving some real world, grounded information on the pluses and minuses of open source software as compared to proprietary software. Sara Davidson and Amy Kautzman (Members of the UC/OCLC Pilot Implementation Team) presented insights in to the benefits and challenges encountered while launching a next-generation consortial catalog (Melvyl) pilot using WCAT Local.

Coastal areas have the largest human population, causing significant urbanization impacts on biodiversity. The coast of Buenos Aires province (Argentina) has touristic cities, which have shown significant growth during the last decades. Therefore, it is fundamental to analyze the effect of urbanization on bird communities. The aim of this study is to analyze the bird communities present in residential areas and implanted forests on coastal dunes in Cariló. Eight fixed radius point counts were carried out in each habitat between spring 2021 and summer 2022. Both habitat types had similar values of species richness, Shannon and Simpson diversity, and functional diversity. However, residential habitat showed higher abundance than the forest. Significant changes between habitats in species composition were found. The Tropical Parula (Setophaga pitiayumi) and the Rufous-collared Sparrow (Zonotrichia capensis) were more abundant in the forest, while the Chimango Caracara (Phalcoboenus chimango), the Monk Parakeet (Myiopsitta monacha) and the Picazuró Pigeon (Patagioenas picazuro) were more abundant in the residential habitat. The residential area had a greater abundance of birds feeding on the ground, the canopy and the air. The results obtained suggest that the urban expansion on implanted forests promotes bird compositional changes, favoring species typical of semi-open habitats and impairing species associated with high tree cover and unmanaged herbaceous vegetation. [ABSTRACT FROM AUTHOR]

Ecological restoration is a viable strategy to recover floristic, structural, and functional attributes of the very vulnerable and widely degraded tropical mountain forests. Most restoration efforts in these highly diverse and narrowly distributed systems involve unassisted forest regeneration or enrichment planting with a small number of species, usually those with commercial value and success evaluated after a few years. We assessed changes in soil attributes, forest composition and structure in four sites with plots under unassisted forest regeneration or enrichment planting. The sites are in the limestone massif of the central highlands of Chiapas (Mexico) and share geological, edaphic and climatic conditions, but differ in level of previous disturbance and the time elapsed since the enrichment planting (16–30 years). No changes in soil variables (contents of C, N, P, and K, cation exchange capacity, and pH) were detected. Total density of juveniles was not consistently related to unassisted forest regeneration or enrichment planting but was highest in the two sites that had severe disturbance level. Influence of enrichment planting on forest regeneration depended on the composition and structure of the surrounding stands, and more so when opportunistic trees like pines and other shade‐intolerant species are available. Yet long‐lived shade‐tolerant species, including oaks, which may have synergistic effects during forest recovery, were well represented in sites with original severe disturbance level. [ABSTRACT FROM AUTHOR]

Brown spot needle blight (BSNB), caused by Lecanosticta acicola (Thüm.) Syd., is an emerging forest disease of Pinus species originating from North America and introduced to Europe and Asia. Severity and spread of the disease has increased in the last two decades in North America and Europe as a response to climate change. No modeling work on spread, severity, climatic suitability, or potential distribution has been done for this important emerging pathogen. This study utilizes a global dataset of 2,970 independent observations of L. acicola presence and absence from the geodatabase, together with Pinus spp. distribution data and 44 independent climatic and environmental variables. The objectives were to (1) identify which bioclimatic and environmental variables are most influential in the distribution of L. acicola; (2) compare four modeling approaches to determine which modeling method best fits the data; (3) examine the realized distribution of the pathogen under climatic conditions in the reference period (1971–2000); and (4) predict the potential future global distribution of the pathogen under various climate change scenarios. These objectives were achieved using a species distribution modeling. Four modeling approaches were tested: regression-based model, individual classification trees, bagging with three different base learners, and random forest. Altogether, eight models were developed. An ensemble of the three best models was used to make predictions for the potential distribution of L. acicola: bagging with random tree, bagging with logistic model trees, and random forest. Performance of the model ensemble was very good, with high precision (0.87) and very high AUC (0.94). The potential distribution of L. acicola was computed for five global climate models (GCM) and three combined pathways of Shared Socioeconomic Pathway (SSP) and Representative Concentration Pathway (SSP-RCP): SSP1-RCP2.6, SSP2-RCP4.5, and SSP5-RCP8.5. The results of the five GCMs were averaged on combined SSP-RCP (median) per 30-year period. Eight of 44 studied factors determined as most important in explaining L. acicola distribution were included in the models: mean diurnal temperature range, mean temperature of wettest quarter, precipitation of warmest quarter, precipitation seasonality, moisture in upper portion of soil column of wettest quarter, surface downwelling longwave radiation of driest quarter, surface downwelling shortwave radiation of warmest quarter and elevation. The actual distribution of L. acicola in the reference period 1971–2000 covered 5.9% of Pinus spp. area globally. However, the model ensemble predicted potential distribution of L. acicola to cover an average of 58.2% of Pinus species global cover in the reference period. Different climate change scenarios (five GCMs, three SSP-RCPs) showed a positive trend in possible range expansion of L. acicola for the period 1971–2100. The average model predictions toward the end of the century showed the potential distribution of L. acicola rising to 62.2, 61.9, 60.3% of Pinus spp. area for SSP1-RCP2.6, SSP2-RCP4.5, SSP5-RCP8.5, respectively. However, the 95% confidence interval encompassed 35.7–82.3% of global Pinus spp. area in the period 1971–2000 and 33.6–85.8% in the period 2071–2100. It was found that SSP-RCPs had a little effect on variability of BSNB potential distribution (60.3–62.2% in the period 2071–2100 for medium prediction). In contrast, GCMs had vast impact on the potential distribution of L. acicola (33.6–85.8% of global pines area). The maps of potential distribution of BSNB will assist forest managers in considering the risk of BSNB. The results will allow practitioners and policymakers to focus surveillance methods and implement appropriate management plans.

We analyse the concentration of caesium-137 (137Cs) in forest litter in relation to forest site conditions. The research was carried out in 2004–2019 in the Krasnogorsk district of the Bryansk region (the Russian Federation). It covered three areas corresponding to the exclusion zone, compulsory resettlement zone, and the zone of residence of the population with the right to resettlement. In all these areas, the concentration of 137Cs in forest litter and the condition of pine stands was studied. We revealed that the forest litter contains more than 90% of 137Cs in all combustible materials. The content of 137Cs in fallen branches, bark, cones, and needles varies from 10 to 15%. More than 50% of the specific activity, which is an indicator of 137Cs content, accounts for needles of pine phytocenoses. In 2019, the best state of pines was recorded for older trees. At the age of 60–80 years, 13% of the studied forest stands were classified as weakened, 87% – as very weakened, and 0% as dying. In the 40–56 age group, dying out and very weakened stands accounted for 50% each, whereas weakened ones were not revealed at all. The interaction between 137Cs and tree age was not identified.

The objective of this study was to apply different types of biological and climatic data in the distribution modeling of tree species in Mexico (Pinus ayacahuite, Pinus montezumae, Pinus oocarpa, Quercus calophylla, and Quercus uxoris). Two types of climate layers (climate types and bioclimatic variables) and three types of biological collection data (presence only data, abundance data, and presence/ absence data) were used for modeling. The results show that there is no one type of biological and climatic data that fits all species. This study evidences that the use of a single type of data may result in underestimation or overestimation in potential distribution areas. [ABSTRACT FROM AUTHOR]

Recommendations for duration of treatment with antipsychotics before considering a switch vary from 2 to 8 weeks, although several studies suggest a rapid onset of action. The objective of this review was to estimate time to onset of action and time to maximum antipsychotic effect of asenapine, olanzapine, quetiapine, and zotepine (pines). We searched bibliographic databases for randomized, placebo-controlled trials in adults with schizophrenia estimating the antipsychotic effect of pines over time. Thirty-five studies including 6331 patients diagnosed with chronic schizophrenia were included. We estimated the standardized mean differences (SMD) of changes in symptom score from baseline to follow-up between intervention and placebo groups across studies using meta-analysis techniques. The summarized effect across all included pines administered as immediate-release formulations showed a statistically significant effect at week 1 (SMD, −0.20 [CI95% −0.28, −0.13]), which increased until week 3 (SMD, −0.42 [CI95% −0.50, −0.34]), after which the effect leveled off (week 6: SMD, −0.53 [CI95% −0.62, −0.44]). The sensitivity analyses of the individual pines confirm this finding, although data sparsity increases variability and limits conclusiveness of these analyses. [ABSTRACT FROM AUTHOR]

Subtropical forest ecosystem encompasses about 1.7% of the total land area of Pakistan and share in country's forest cover is ~32%. A blend of imperative services is being provided by this ecosystem. Tree species control forest ecosystem and directly influence soil productivity. Soil structure and fertility status are improved by litter fall and humus formation that is greatly dependent on plant species. Present study investigated the role of dominant tree species in improving soil profile concerning subtropical forest ecosystem. The study area was district Lower Dir in North-West Pakistan. Five sites were selected for composite soil sampling to take in three forest cover types i.e. chir pine, blue pine and mixed forests. The collected soil samples were anal yzed for physical and chemical characteristics using conventional methods. Soil pH, phosphorus and potassium showed significant influence of forest cover type. Organic matter and nitrogen present in soil showed meaningful relation. However, soil EC and BD results appeared to have low influence of vegetation. Generally, vegetation enhances organic matter in soil due to plant decay and litter fall but non-significant difference was observed for forest cover type. [ABSTRACT FROM AUTHOR]

Various spatial modelling methods and tools have been used in ecology and biogeography. The application of these options serves a dual function: first, they offer information about the potential distribution of species to understand the richness and diversity of unassessed areas. Second, spatial modelling methods employ these predictions to select relevant sites to determine natural conservation areas. In this study, we compared three methods for modelling the spatial distribution of Egg-cone Pine (Pinus oocarpa Schiede), an important non-timber pine in Mexico. The final goal is to estimate suitable areas for the conservation and reproduction of superior individuals (plus trees) of P. oocarpa as a conservation strategy outside the known distribution since this species possesses a high ecological and economic value. The model used were a generalised linear model (GLM) as a parametric regression method, random forest (RF) as a machine-learning method, and the MaxEnt model, a standard procedure, implemented using the Kuenm R package. The results suggest that the models used performed well since the AUROC was between 0.95 and 0.98 in all cases. MaxEnt and random forest approaches provided more conservative predictions for the distribution of suitable areas of plus trees of P. oocarpa than the generalised linear model, but the random forest algorithm achieved the best performance. The results of the study allowed the determination of ex situ conservation areas for P. oocarpa plus trees outside of their known distribution. [ABSTRACT FROM AUTHOR]

The current national standard for strength grading in Spain is based on a visual classification, which, for softwood species with small cross-sections (with a thickness equa tol or less than 70 mm), establishes two different visual grades (ME-1 and ME-2). These grades are assigned to the strength classes C24 and C18, respectively, for maritime and radiata pines, and C27 and C18 for Scots pine, according to the European standard EN-1912:2012. The production of engineered wood products, such as glulam or cross-laminated timber is increasing worldwide. The machine grading of wood using non-destructive testing provides the industry with a more reliable, fast, and consistent method for grading. With this background in mind, this study presents the yield comparison of machine grading vs. visual grading for those three pine species from Spain. The machine settings were obtained according to the standard EN 14081-2:2019, providing several possible strength grade combinations. Results allow new possibilities for the industry and improve the structural yield of the studied timber, thus increasing the material optimization. [ABSTRACT FROM AUTHOR]

Pine wood nematode, Bursaphelenchus xylophilus, is a worldwide pest of pine trees, spreading at an alarming rate and with great ecological adaptability. In the process of causing disease, the nematode causes metabolic disorders and changes in the endophytic microbial community of the pine tree. However, the changes at the pine nidus during early nematode invasion have not been well studied, especially the differential metabolites, in Pinus massoniana, the main host of B. xylophilus in China. In this study, we analyzed the endophytic bacterial and fungal communities associated with healthy and B. xylophilus-caused wilted pine trees. The results show that 1333 bacterial OTUs and 502 fungal OTUs were annotated from P. massoniana stem samples. The abundance of bacterial communities in pine trees varies more following infection by B. xylophilus, but the abundance changes of fungal communities are less visible. There were significant differences in endophytic microbial diversity between wilted and healthy P. massoniana. In wilted pine trees, Actinobacteria and Bacteroidia were differential indicators of bacterial communities, whereas, in healthy pine trees, Rhizobiales in the Proteobacteria phylum were the major markers of bacterial communities. Meanwhile, the differential markers of fungal communities in healthy pines are Malasseziales, Tremellales, Sordariales, and Fusarium, whereas Pleosporaceae is the key marker of fungal communities in wilted pines. Our study examines the effect of changes in the endophytic microbial community on the health of pine trees that may be caused by B. xylophilus infection. In parallel, a non-targeted metabolomic study based on liquid mass spectrometry (LC-MS) technology was conducted on pine trees inoculated with pine nematodes and healthy pine trees with a view to identifying key compounds affecting early pine lesions. Ultimately, 307 distinctly different metabolites were identified. Among them, the riboflavin metabolic pathway in pine trees may play a key role in the early pathogenesis of pine wood nematode disease. [ABSTRACT FROM AUTHOR]

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The information about the impacts of thinning on the availability of micro-nutrients, as well as macro-nutrients other than N, P and K, is still scarce. We assessed the changes in the concentrations of 12 elements (Al, B, Ca, Cu, Fe, K, Mg, Mn, N, Na, P and Zn) with needle age (current year or 1-year-old) and three early thinning treatments in two of the most widely distributed pines in SW Europe: P. pinaster and P. radiata. Four treatments were setup in triplicate: control (C), light thinning (LT), heavy thinning (HT) and selection thinning of dominant trees (ST), with 0%, 10%, 20% and 20% of total basal area removed, respectively. Needle δ15N varied little with needle age and most thinning treatments in both species, but ST triggered an increase of N in P. pinaster needles. Needle Ca and Na increased with age, but were unaffected by treatment. Foliar K, Zn and Cu decreased with age in both species and increased with ST only in P. pinaster. Jointly considering all treatments, there was no needle age effect on Mn concentration, neither in P. radiata nor in P. pinaster, but in the latter species Mn levels increased with age in the selection thinning plots. There were significant thinning effects on Mn levels in both P. pinaster (ST>C) and P. radiata (HT > LT, ST). Foliar Fe and Al concentration increased with age in both pines; the former increased with ST only in P. pinaster while the latter was affected by thinning only in current year needles and without a clear tendency. Neither age nor treatment effects on needle Mg and B were found, while for P needle age had a significant effect only in P. pinaster.

This article is a Commentary on Buck et al. (2023), 237: 2435–2449. [ABSTRACT FROM AUTHOR]

Premise: Accurate species delimitation is essential for evolutionary biology, conservation, and biodiversity management. We studied species delimitation in North American pinyon pines, Pinus subsection Cembroides, a natural group with high levels of incomplete lineage sorting. Methods: We used coalescent‐based methods and multivariate analyses of low‐copy number nuclear genes and nearly complete high‐copy number plastomes generated with the Hyb‐Seq method. The three coalescent‐based species delimitation methods evaluated were the Generalized Mixed Yule Coalescent (GMYC), Poisson Tree Process (PTP), and Trinomial Distribution of Triplets (Tr2). We also measured admixture in populations with possible introgression. Results: Our results show inconsistencies among GMYC, PTP, and Tr2. The single‐locus based GMYC analysis of plastid DNA recovered a higher number of species (up to 24 entities, including singleton lineages and clusters) than PTP and the multi‐locus coalescent approach. The PTP analysis identified 10 species whereas Tr2 recovered 13, which agreed closely with taxonomic treatments. Conclusions: We found that PTP and GMYC identified species with low levels of ILS and high morphological divergence (P. maximartinezii, P. pinceana, and P. rzedowskii). However, GMYC method oversplit species by identification of more divergent samples as singletons. Moreover, both PTP and GMYC were incapable of identifying some species that are readily identified morphologically. We suggest that the divergence times between lineages within North American pinyon pines are so disparate that GMYC results are unreliable. Results of the Tr2 method coincided well with previous delimitations based on morphology, DNA, geography, and secondary chemistry. [ABSTRACT FROM AUTHOR]

A general investigation of sub-tropical forests, from Pir Chinasi National Park, Tolipir National Park, Dhirkot Nature Reserve and Banjosa Game Reserve was carried out during different months from February 2008 to May 2010. The relative abundance of species was calculated using line transects of 50m. A total of five different species (Abies pindrow. Cedrus deodara, Pinus wallichiana, Pinus roxburgii and Picea smithiana) from the Pinaceae family were recorded. The main reported use of Cedrus deodara and Pinus wallichiana by the local people was for furniture and construction purposes. Pinus wallichiana was observed as the dominant species from all the selected sites.

Background: Pinus (Coniferophyta) and Laccaria (Basidiomycota) establish ectomycorrhizal symbioses in natural forests. However, their detailed morphoanatomical and phylogenetic characterization have received little attention. Accurate identification of native host symbionts is of paramount relevance to the production of mycorrhized seedlings for successful reforestation programs. Questions/Objective: We aimed to determine if L. squarrosa is able to establish ectomycorrhizal symbiosis with gymnosperms, thereby widening its host range and highlighting its relevance as a potential inoculant for pine seedlings. Currently, L. squarrosa is only known from its type collection associated with the angiosperm Fagus grandifolia var. mexicana. Studied species: The fungus L. squarrosa and Pinus pseudostrobus, a tree endemic to Mexico. Study site and dates: A Pinus-Quercus forest in Piedra Canteada, Nanacamilpa, Tlaxcala; 2018-2020. Methods: L. squarrosa basidiomata were identified and ectomycorrhizal roots were collected and morphoanatomically characterized. For molecular identification, DNA was extracted, PCR was performed targeting the nuclear ribosomal internal transcribed spacer region (nucrDNA ITS) for the mycobiont identification and the chloroplastic single-locus trnL region for the phytobiont. Results: In the phylogenetic analyses, our sequences from basidiomata and ectomycorrhizae clustered together with L.squarrosa with high values of supporting identity. Meanwhile, P. pseudostrobus was molecularly identified as the phytobiont. Conclusions: This is one of the few worldwide characterizations of Laccaria ectomycorrhiza under field conditions and contributes to the understanding of the ecology, distribution, and economic relevance of the symbiotic association. Our data suggest that L. squarrosa has potential for use as a native inoculant for P. pseudostrobus tree production. Translate stop Translate stop

Recommendations for duration of treatment with antipsychotics before considering a switch vary from 2 to 8 weeks, although several studies suggest a rapid onset of action. The objective of this review was to estimate time to onset of action and time to maximum antipsychotic effect of asenapine, olanzapine, quetiapine, and zotepine (pines). We searched bibliographic databases for randomized, placebo-controlled trials in adults with schizophrenia estimating the antipsychotic effect of pines over time. Thirty-five studies including 6331 patients diagnosed with chronic schizophrenia were included. We estimated the standardized mean differences (SMD) of changes in symptom score from baseline to follow-up between intervention and placebo groups across studies using meta-analysis techniques. The summarized effect across all included pines administered as immediate-release formulations showed a statistically significant effect at week 1 (SMD, −0.20 [CI95% −0.28, −0.13]), which increased until week 3 (SMD, −0.42 [CI95% −0.50, −0.34]), after which the effect leveled off (week 6: SMD, −0.53 [CI95% −0.62, −0.44]). The sensitivity analyses of the individual pines confirm this finding, although data sparsity increases variability and limits conclusiveness of these analyses.

Pine wood nematode, Bursaphelenchus xylophilus, is a worldwide pest of pine trees, spreading at an alarming rate and with great ecological adaptability. In the process of causing disease, the nematode causes metabolic disorders and changes in the endophytic microbial community of the pine tree. However, the changes at the pine nidus during early nematode invasion have not been well studied, especially the differential metabolites, in Pinus massoniana, the main host of B. xylophilus in China. In this study, we analyzed the endophytic bacterial and fungal communities associated with healthy and B. xylophilus-caused wilted pine trees. The results show that 1333 bacterial OTUs and 502 fungal OTUs were annotated from P. massoniana stem samples. The abundance of bacterial communities in pine trees varies more following infection by B. xylophilus, but the abundance changes of fungal communities are less visible. There were significant differences in endophytic microbial diversity between wilted and healthy P. massoniana. In wilted pine trees, Actinobacteria and Bacteroidia were differential indicators of bacterial communities, whereas, in healthy pine trees, Rhizobiales in the Proteobacteria phylum were the major markers of bacterial communities. Meanwhile, the differential markers of fungal communities in healthy pines are Malasseziales, Tremellales, Sordariales, and Fusarium, whereas Pleosporaceae is the key marker of fungal communities in wilted pines. Our study examines the effect of changes in the endophytic microbial community on the health of pine trees that may be caused by B. xylophilus infection. In parallel, a non-targeted metabolomic study based on liquid mass spectrometry (LC-MS) technology was conducted on pine trees inoculated with pine nematodes and healthy pine trees with a view to identifying key compounds affecting early pine lesions. Ultimately, 307 distinctly different metabolites were identified. Among them, the riboflavin metabolic pathway in pine trees may play a key role in the early pathogenesis of pine wood nematode disease.

The effect of Scleroderma verrucosum (Vaill) Pers and Rhizopogon luteolus Fr. & Nordh. was evaluated on the morphological and biological quality of Pinus radiata D. Don plants in a nursery in Vilcashuaman, Ayacucho, Peru. Treatments: (1) Mycorrhization with Scleroderma verrucosum, (2) Mycorrhization with Rhizopogon luteolus, (3) Mixture of both fungi, and (4) Control, in a completely randomized design with 10 repetitions per treatment. The fungi came from local Pinus radiata and Eucalyptus globulus forests. The inoculation was carried out in the peal at 30 days of sowing and the evaluation at 7.5 months after the peal. The mycorrhizal pines outperformed the control with significant differences in all the variables evaluated. In the stem neck diameter and dry matter of the aerial part, the inoculated treatments did not present significant differences; however, in the height, dry matter of the root, and total dry matter, the Mixture treatment stood out. In the biological quality, a greater number of mycorrhizae was observed in the inoculated, with significant differences compared to the control without mycorrhizae. A higher percentage of monopodial mycorrhizae (91%) was evidenced in relation to dichotomous (8.5%) and coralloid (0.6%) types. Significant positive relationships were determined between the morphological variables, but these on P. radiata presented non-significant associations with the number of mycorrhizae. The individual and in mixture use of wild ectomycorrhizal fungi increased the morphological and biological quality of P. radiata; therefore, the application of these fungi is recommended for the production of seedlings in nurseries in Vilcashuaman and other high-Andean areas. [ABSTRACT FROM AUTHOR]

With the current rate of biodiversity loss, conservation management practices require a comprehensive understanding of eco‐evolutionary relationships, history, and genetic structure of species. Assessments of genetic diversity are crucial, especially in rare, endemic, or threatened forest tree species with small and isolated populations, such as peat bog pine (Pinus uliginosa N.). Here, we used a novel approach, combining genetic diversity assessment, ecological niche modeling, and population demography inference to explore the complex history of a few remnant populations of this endangered pine. To asses the relative influence of isolation and fragmentation on genetic diversity in the taxonomic context, the patterns of genetic variation found in P. uliginosa were contrasted with those observed in its close relatives with much bigger distribution ranges and larger populations (Pinus sylvestris, Pinus mugo, and Pinus uncinata). We found a similar level of genetic diversity across the species at nuclear loci but contrasting patterns of variability distribution at chloroplast markers. We detected the signatures of an ancient genetic bottleneck dated at around 26 400 years ago, indicating a drastic reduction in the population size of P. uligionosa during the Last Glacial Maximum. In addition, we found substantial differentiation between current populations as a result of enhanced genetic drift during long‐lasting isolation. The research suggests potential conservation management strategies for peat bog pine and emphasizes the importance of using complementary approaches for their successful development. [ABSTRACT FROM AUTHOR]

Pinewood nematode, Bursaphelenchus xylophilus, is one of the greatest threats to pine trees and is spreading all over the world. During the nematode's pathogenesis, plant microorganisms play important roles. However, many microbial communities, such as that in Pinus massoniana, a major host of B. xylophilus that is widely distributed in China, are not well studied, especially the fungal communities. Here, the endophytic and rhizospheric bacterial and fungal communities associated with healthy and B. xylophilus–infected P. massoniana were analyzed. The results showed that 7639 bacterial and 3108 fungal OTUs were annotated from samples of P. massoniana, the rhizosphere, and B. xylophilus. There were significant diversity differences of endophytic microbes between healthy and infected P. massoniana. The abundances of endophytic bacteria Paenibacillus, unidentified_Burkholderiaceae, Serratia, Erwinia, and Pseudoxanthomonas and fungi Penicillifer, Zygoascus, Kirschsteiniothelia, Cyberlindnera, and Sporothrix in infected pines were greater than those in healthy pines, suggesting an association of particular microbial abundances with the pathogenesis of B. xylophilus in pines. Meanwhile, the abundances of microbes of unidentified_Burkholderiaceae, Saitozyma, and Pestalotiopsis were greater and Acidothermus and Trichoderma were lower in the rhizosphere under infected pines than those under healthy pines and the differences might be caused by B. xylophilus–induced weakening of the health of pines. Our study explored the endophytic and rhizospheric microbial community changes potentially caused by B. xylophilus infection of pines. [ABSTRACT FROM AUTHOR]

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