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Most of Earths trees rely on critical soil nutrients that ectomycorrhizal fungi (EcMF) liberate and provide, and all of Earths land plants associate with bacteria that help them survive in nature. Yet, our understanding of how the presence of EcMF modifies soil bacterial communities, soil food webs, and root chemistry requires direct experimental evidence to comprehend the effects that EcMF may generate in the belowground plant microbiome. To this end, we grew Pinus muricata plants in soils that were either inoculated with EcMF and native forest bacterial communities or only native bacterial communities. We then profiled the soil bacterial communities, applied metabolomics and lipidomics, and linked omics data sets to understand how the presence of EcMF modifies belowground biogeochemistry, bacterial community structure, and their functional potential. We found that the presence of EcMF (i) enriches soil bacteria linked to enhanced plant growth in nature, (ii) alters the quantity and composition of lipid and non-lipid soil metabolites, and (iii) modifies plant root chemistry toward pathogen suppression, enzymatic conservation, and reactive oxygen species scavenging. Using this multi-omic approach, we therefore show that this widespread fungal symbiosis may be a common factor for structuring soil food webs.IMPORTANCEUnderstanding how soil microbes interact with one another and their host plant will help us combat the negative effects that climate change has on terrestrial ecosystems. Unfortunately, we lack a clear understanding of how the presence of ectomycorrhizal fungi (EcMF)-one of the most dominant soil microbial groups on Earth-shapes belowground organic resources and the composition of bacterial communities. To address this knowledge gap, we profiled lipid and non-lipid metabolites in soils and plant roots, characterized soil bacterial communities, and compared soils amended either with or without EcMF. Our results show that the presence of EcMF changes soil organic resource availability, impacts the proliferation of different bacterial communities (in terms of both type and potential function), and primes plant root chemistry for pathogen suppression and energy conservation. Our findings therefore provide much-needed insight into how two of the most dominant soil microbial groups interact with one another and with their host plant.

Whitebark pine (WBP, Pinus albicaulis) is a white pine of subalpine regions in the Western contiguous United States and Canada. WBP has become critically threatened throughout a significant part of its natural range due to mortality from the introduced fungal pathogen white pine blister rust (WPBR, Cronartium ribicola) and additional threats from mountain pine beetle (Dendroctonus ponderosae), wildfire, and maladaptation due to changing climate. Vast acreages of WBP have suffered nearly complete mortality. Genomic technologies can contribute to a faster, more cost-effective approach to the traditional practices of identifying disease-resistant, climate-adapted seed sources for restoration. With deep-coverage Illumina short reads of haploid megagametophyte tissue and Oxford Nanopore long reads of diploid needle tissue, followed by a hybrid, multistep assembly approach, we produced a final assembly containing 27.6 Gb of sequence in 92,740 contigs (N50 537,007 bp) and 34,716 scaffolds (N50 2.0 Gb). Approximately 87.2% (24.0 Gb) of total sequence was placed on the 12 WBP chromosomes. Annotation yielded 25,362 protein-coding genes, and over 77% of the genome was characterized as repeats. WBP has demonstrated the greatest variation in resistance to WPBR among the North American white pines. Candidate genes for quantitative resistance include disease resistance genes known as nucleotide-binding leucine-rich repeat receptors (NLRs). A combination of protein domain alignments and direct genome scanning was employed to fully describe the 3 subclasses of NLRs. Our high-quality reference sequence and annotation provide a marked improvement in NLR identification compared to previous assessments that leveraged de novo-assembled transcriptomes.

The grasslands and shrub areas of the Patagonian steppe are the most frequent habitat for the "Near Threatened" armadillo, known as pichi (Zaedyus pichiy). Dense exotic conifer plantations are replacing the steppe in Argentinean northern Patagonia. This study aimed to evaluate the effect of conifer afforestation on the occurrence and food availability in a Z. pichiy population in north-western Patagonia. Fifteen sites in the native steppe and 50 in exotic pine plantations were sampled. We recorded the number of signs of pichi's presence and the diversity of invertebrates. Signs of Z. pichiy presence decreased in pine afforestation compared to the native steppe. Additionally, we found a decrease in the abundance, richness, diversity, and biomass of arthropods in pine plantations. Therefore, the presence of pine plantations in the steppe reduces the main food items of Z. pichiy and also eliminates the native steppe vegetation structure that provides preferred places to dig burrows. Pine monocultures do not provide a suitable habitat for Z. pichiy and may exacerbate the degradation of an already disturbed environment. [ABSTRACT FROM AUTHOR]

Deciduous forests in northeastern North America are comprised of a mixture of ectomycorrhizal (EM) and arbuscular mycorrhizal (AM) trees. However, land use legacies and other factors have decreased EM and concomitantly increased AM tree dominance, potentially limiting forest ecosystem functioning. We investigated how scattered EM tree patches and soil inoculum from local EM tree‐dominated forests influence EM fungal colonisation, survival and growth of EM Tsuga canadensis, Pinus strobus and Quercus spp. tree seedlings in AM‐dominated secondary forests.Seedlings were planted next to dominant AM Acer and scattered EM Betula trees across three New York secondary forests. A subset of seedlings also received soil inoculum from local EM‐dominated forests. We monitored the survival and height growth of seedlings for 2 years and then measured seedling shoot biomass, assessed EM colonisation and identified EM fungi from seedling roots.All genera of seedlings planted near EM Betula had higher EM colonisation and fungal richness than those planted near AM Acer trees. Inoculation with EM forest soil increased EM colonisation and fungal richness of seedlings only near AM Acer, showing great effectiveness in areas lacking native EM fungi. Total EM fungal diversity on seedling roots was highest near EM Betula, which included numerous taxa usually associated with mature trees. In contrast, EM fungal communities near AM Acer were sparse and mostly dominated by relatively few taxa of spore‐bank fungi. Although seedling survival did not differ between treatments, soil inoculation and proximity to EM Betula increased second‐year height growth of Pinus and Tsuga while soil inoculation alone significantly enhanced shoot mass of Quercus seedlings.Synthesis. Agricultural land use legacies have resulted in expansive secondary forests dominated by AM trees. In these forests, establishment of EM tree seedlings outside existing EM tree patches may be hindered by a lack of EM fungi, but local soil inoculum from EM tree‐dominated forests can reintroduce native EM fungi into secondary forests lacking established EM trees. [ABSTRACT FROM AUTHOR]

Summary: Studies have explored how traits separate plants ecologically and the trade‐offs that underpin this separation. However, uncertainty remains as to the taxonomic scale at which traits can predictably separate species. We studied how physiological traits separated three Pinus (Pinus banksiana, Pinus resinosa, and Pinus strobus) species across three sites.We collected traits from four common leaf and branch measurements (light–response curves, CO2–response curves, pressure–volume curves, and hydraulic vulnerability curves) across each species and site. While common, these measurements are not typically measured together due to logistical constraints.Few traits varied across species and sites as expected given the ecological preferences of the species and environmental site characteristics. Some trait trade‐offs present at broad taxonomic scales were observed across the three species, but most were absent within species. Certain trade‐offs contrasted expectations observed at broader scales but followed expectations given the species' ecological preferences.We emphasize the need to both clarify why certain traits are being studied, as variation in unexpected but ecologically meaningful ways often occurs and certain traits might not vary substantially within a given lineage (e.g. hydraulic vulnerability in Pinus), highlighting the role a trait selection in trait ecology. [ABSTRACT FROM AUTHOR]

Anticipating the effects of global change on biodiversity has become a global challenge requiring new methods. Approaches like species distribution models have limitations which have fueled the development of joint species distribution models (JSDMs). However, JSDMs rely on systematic surveys community data, and no assessment has been made of their suitability with unstructured opportunistic databases data. We used hierarchical modeling of species communities (HMSC) to test JSDMs performance when using opportunistic databases. Using artificial data that mimic the limitations of such databases by subsampling complete co‐occurrence matrices (i.e. original data), we analysed how the completeness of opportunistic databases affects JSDMs regarding 1) the role of independent variables on species occurrence, 2) residual species co‐occurrence (as a proxy of biotic interactions) and 3) species distributions. Moreover, we illustrate how to evaluate completeness at the pixel level of real data with a study case of forest tree species in Europe, and evaluate the role of data completeness in model estimation. Our results with artificial data demonstrate that decreasing the completion percentage (the rate of original data presences represented in the subsampled matrices) increases false negatives and negative co‐occurrence probabilities, resulting in a loss of ecological information. However, HMSC tolerates different levels of degradation depending on the model aspect being considered. Models with 50% of missing data are valid for estimating species niches and distribution, but interaction matrices require databases with at least 75% of completion data. Furthermore, HMSC's predictions often resemble the original community data (without false negatives) even more than the subsampled data (with false negatives) in the training dataset. These findings were confirmed with the real study case. We conclude that opportunistic databases are a valuable resource for JSDMs, but require an analysis of data completeness for the target taxa in the study area at the spatial resolution of interest. [ABSTRACT FROM AUTHOR]

The use of intensive silviculture to increase forest productivity in commercial plantations will undoubtedly persist into the future. This review synthesizes and analyses studies that have investigated the influence of fertilization on density, microfibril angle (MFA), and modulus of elasticity (MOE) of different Pinus species under intensive management. It was found that in general, ring width or growth rate demonstrated a negative correlation with density, and a positive relationship with MFA. Also, the relationship between growth rate and density and MFA were age specific and often non-significant at the whole stem level. Earlywood and latewood were influenced differently by fertilization: Earlywood width and density increased while in latewood, width stayed constant but density decreased. This resulted in a decrease in within-ring heterogeneity of density and density-related properties. Since latewood generally contributed more to whole-ring density, the net effect was that whole-ring wood density of pines mostly decreased with fertilization. Given that fertilization often resulted in a decrease in wood density and an increase in MFA, MOE decreased with fertilization. Most fertilization-wood-property studies on Pinus involved nitrogen and phosphorus fertilizers with differing quantity and ratios. Results suggest that nitrogen may cause the greatest change in wood growth and properties. An important question that was often unanswered in research, was whether the effect of specific fertilization treatments on wood properties were purely based on the influence of increased growth or whether there were direct influences not explained by growth. Also, despite potassium being an important elemental component of many fertilizers, relatively little work has been done to determine its effect on wood properties. [ABSTRACT FROM AUTHOR]

Fusarium circinatum is a globally important fungal pathogen that causes pitch canker on a wide range of Pinus species. In this study, we considered mycelial growth in culture and aggressiveness of a South African population of F. circinatum isolates. The specific aim was to determine how these phenotypes are correlated with one another and other isolate characteristics, including mating type, host species and geographic origin of the isolates. The study involved the selection of 102 isolates of F. circinatum from five provinces of South Africa based on genotype, mating type and original host from which they were isolated, after which pathogenicity tests were carried out on Pinus patula seedlings. Mycelial growth in culture was also determined for all the isolates at three different temperatures. In the pathogenicity tests, most of the isolates produced significant lesions. While seven had low levels of aggressiveness, other isolates tested were as or more aggressive than a standard set of isolates routinely used for resistance/ tolerance screening. Most F. circinatum isolates grew best at 25 °C, followed by growth at 20 °C and 30 °C. A notable correlation between aggressiveness and the geographical origin was identified. Moreover, the study highlighted a moderately positive relationship between the growth rate of F. circinatum isolates and their reported aggressiveness. The extensive data gathered on the aggressiveness of F. circinatum will offer a broad range of isolates for future comparative studies using other genotypes of F. circinatum and will also aid in the consideration of F. circinatum isolates used for tolerance screening studies. [ABSTRACT FROM AUTHOR]

Previous studies examining the influence of understory shrubs and light transmittance through the canopy (LT) (%) on seedling establishment of desired species and litter decomposition have reported inconsistent findings. Uncertainty still also remains about the effects of understory junipers (Juniperus oxycedrus L. subsp. oxycedrus) and LT on survival and growth of black pine (Pinus nigra Arnold.) seedlings as well as on litter decomposition across species' geographical range. Thus, this study aimed to examine the influence of understory junipers and LT on the growth and survival of black pine seedlings. Moreover, how junipers and LT affect litter decomposition was also monitored for eighteen months. Survival and growth of seedlings were most significantly affected by LT and understory junipers. LT and junipers negatively affected the survival of black pine seedlings. LT increased root-collar diameter (RCD) growth of the seedlings, while the RCD growth rate decreased with the presence of understory junipers. Moreover, the influences of LT and junipers on litter mass loss were mainly statistically significant; the presence of junipers and increasing LT in understory retarded litter decomposition. The findings may help our knowledge of ecological processes such as litter decomposition and seedling establishment in black pine forests. The results would also provide important guidance for evaluating the effects of overstory thinning (i.e., providing light to understory) and removing junipers on the ecological processes associated with litter decomposition and seedling recruitment in a black pine stand. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Changes in land use and land cover (LULC) can largely decrease water quality across spatial scales. Watercourse degradation is caused mainly by urbanization, however other activities such as agriculture can also negatively affect the water quality. Regional characteristics may produce specific responses to different changes in the river basin, but there is few information from some regions and landscapes (e.g. Pinus silviculture). Here we compared two river basins in southern Brazil: Antas River subbasin (urban) and Faxinalzinho Stream Basin (agricultural). LULC was evaluated in the basin and at three sample points—at 450 m proximity buffers. We collected aquatic macroinvertebrates (AMI) and identified them at the family and genus levels to calculate biotic indices. LULC and AMI data were associated with the NMDS and redundancy analyzes. We observed high percentage of vegetation in both basins, with predominance of urban + rural areas in the Antas River and mostly rural area in Faxinalzinho Stream. Biotic indices showed good water quality in the rural watercourse, NMDS and RDA associated resistant taxa with urbanization, showing the sufficiency of family-level identification for water quality assessment. Despite presenting good conditions, the Pinus associated stream requires proper management to maintain its quality, and the urban river urgently requires recovery endeavours. [ABSTRACT FROM AUTHOR]

Ectotherms are largely impacted by extreme climate events, essentially heatwaves. In Tunisia, the pine processionary moth (PPM), Thaumetopoea pityocampa, is a defoliator typically laying eggs in summer. Its geographical range is expanding northwards in Europe while retracting from southern Tunisia where summer temperatures can reach extreme heats. We explored the effects of climate change over the last 30 years on PPM at its southern range edge. We investigated variations of fecundity and causes of egg mortality over time using historical and contemporary collections of egg masses. Due to incomplete historical series, a clustering method was used to group climatically homologous sampling sites and perform allochronic analyses on clusters instead of individual localities. Our results suggest negative effects of summer heat on egg survival, down to 0% hatching rate in one site during a major heatwave. Such high hatching failures resulted partly from high egg sterility and aborted embryos, with little effects of parasitism rate, suggesting heat susceptibility during embryonic development, but our results do not allow distinguishing impeded mating success from failed egg maturation or early embryo death. Decreasing female fecundity was observed in regions where allochronic comparisons were possible, associated with a decrease in parasitism rate, while climatic variability increased. Previous studies have confirmed experimentally the thermal sensitivity of PPM early instars to temperatures observed in the present work, including one population from southern Tunisia. However, further work is required to evaluate the relative importance of warming summers among populations, since the risk of heat stress depends on the phenology of sensitive instars, and populations from the warmest areas may not necessarily be the most vulnerable to climate change if they already evolved phenological heat avoidance. In addition to heat‐induced mortality, the ultimate fitness of heat survivors should also be explored to determine potential carry‐over effects on subsequent life stages. [ABSTRACT FROM AUTHOR]

Indented growth rings were found long ago to be experimentally induced in Pinus halepensis Miller by thin parallel axial scratching of the bark up to the vascular cambium with a sharp blade. Here, we show that when the bark and vascular cambium of P. halepensis are wounded by wide and long parallel axial wounds ("windows") rather than by thin scratches, the induced indented growth rings become dramatically more indented. All ten trees that were wounded by long parallel "windows" responded with very strong growth (especially in the first two years) that resulted in the formation of very conspicuous, extremely indented growth rings in the wood formed in between the long and wide woundings. This is true for both the trunks that were wounded all around their circumference and those that were wounded only in part of their circumference. We also suggest further lines of research. [ABSTRACT FROM AUTHOR]

The mutualistic interaction between trees and ectomycorrhizal fungi (EMF) can have a major effect on forest dynamics and specifically on seedling establishment. Here, we compared the EMF community composition associated with the roots of young saplings and mature trees of two co-habiting Pinaceae: Pinus halepensis and Cedrus deodara growing together in a post-fire forest plot, using fungal ITS metabarcoding. We found that the differences in the EMF community between the two sapling groups were mostly attributed to changes in the relative abundance of specific fungal species, with little species turnover. Specifically, Tomentella showed high abundance on pine roots, while Tuber , Russula and Sebacina were more common on the roots of cedars. The physical proximity to a specific host species was correlated with the EMF community composition of young saplings. Specifically, regardless of the sapling's own identity, the roots of saplings growing next to mature cedars had higher abundance of Tuber species, while Tomentella coerulea (Höhn. & Litsch) , Russula densifolia (Secr. ex Gillet) and Tuber nitidum (Vittadini) dominated saplings next to mature pines. Cedar saplings' shoot structure was correlated with a specific EMF species. Overall, these results suggest that when germinating next to mature trees, the EMF community of saplings could be determined by extrinsic factors such as the small-scale distribution of mature trees in the forest. [ABSTRACT FROM AUTHOR]

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Various parts of the Pinaceae species, a traditional plant, have potential health benefits and exhibit antibacterial, anti-cancer, and antioxidant activities. This study aims to investigate the biochemical properties of both petal (P) and core (C) fractions from pinecones of P. halepensis (PA), P. brutia (PB), and P. pinea (PP). Pinecones were manually separated into P and C, which were then milled to investigate maceration with solvents of increasing polarity: cyclohexane (1SV), ethyl acetate (2SV), and methanol (3SV) at 20 °C. Spectrophotometry was utilized to quantify the total phenolic content (TPC) and to assess bioactivities. Gas chromatography with mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC) were employed to identify the chemical composition. 3SV extracts demonstrated the highest TPC and a significant anti–oxidant potential. PA-P-3SV exhibited the highest TPC (460.66 mg GAE/g DW) and PP-P-3SV displayed the best IC50 (10.54 µg/mL) against DPPH. 1SV and 2SV extracts showed interesting anticancer activity against Hela and HepG2 cells. No significant toxic effect of P and C extracts from pinecones was observed on HEK-293 cells. GC-MS analysis unveiled 46 volatile compounds, of which 32 were detected for the first time in these species. HPLC analysis identified 38 compounds, of which 27 were not previously detected in these species. This study highlights the significant potential of pinecones as a rich source of bioactive compounds. [ABSTRACT FROM AUTHOR]

Coniferous forests represent one of the most valuable ecosystems worldwide, due to the ecological and economic services they provide. Pinus pseudostrobus Lindl., is one of the most promising species for its use in reforestation programs, so it was proposed in this work to evaluate the effect of different LED light spectra on the induction of photomorphogenic responses. To this end, the effects of different light sources (red LED, blue LED, red + blue LED, white LED, and fluorescent light) on the induction and characteristics of callus formed from transverse thin cell layers (tTLC) of hypocotyls of P. pseudostrobus in vitro plantlets were evaluated. The best results in terms of callus characteristics formed were obtained from hypocotyl segments grown on a WPM medium containing 1 mg L-1 of BAP and 3 mg L-1 of 2,4-D, under a blue LED light spectrum. Evaluating technologies to solve challenges that limit forest production such as recalcitrance of forest species is important to sustain the services provided by species as important as forest conifers. [ABSTRACT FROM AUTHOR]

Considerable research has focused on gene silencing in tree-feeding insects, but how trees recognize and process double-stranded RNA (dsRNA) engineered to target plant pests is unknown. We performed transcriptomic assembly, preliminary differential expression analysis, and in silico annotation on loblolly pine (Pinus taeda, L.) seedlings exposed to southern pine beetle-specific dsRNA. This pilot study sought to elucidate the baseline response of seedlings challenged with insect-specific dsRNA. Treated and untreated seedlings were sequenced and following transcriptome assembly 20 RNAi-related proteins (RRPs) were annotated. Differential gene expression analysis conducted using DESeq2 followed by pathway enrichment revealed 7131 differentially expressed transcripts, of which 33% were upregulated and 67% were downregulated. Only two RRPs selected for analysis were upregulated in treated seedlings, showing a lack of detectable RNAi response with our methodology. Beyond RNAi-related proteins, pathway enrichment mapped to immune response systems and genetic and cellular processing. Upregulated transcripts included autophagy, amino sugar and nucleotide sugar metabolism, and plant hormone signal transduction. Downregulated transcripts included RNA degradation and fatty acid metabolism pathways. Multiple DICER-LIKE and ARGONAUTE proteins were also annotated in five other North American pines, revealing diversity among these crucial proteins. Understanding host plant response to RNAi-mediated pest control is essential to further develop this technology against tree pests. [ABSTRACT FROM AUTHOR]

Fire has long been recognized as a significant evolutionary factor for the genus Pinus (family Pinaceae). Many pine species have developed specific fire-adaptations, such as self-pruning, resprouting, and serotiny, to persist under various fire regimes. Fire-related traits, such as needle length, bark thickness, and plant height, also can affect the survival of pines in fire-prone environments. Investigating the climate conditions of pines and analyzing the variation in fire-adaptations and fire-related traits across pines can provide insights into the evolutionary process of the genus Pinus affected by fire. However, such studies are rare, particularly those focusing on the relationship among environmental conditions, fire-adaptations, and fire-related traits with a large number of pine species. In this study, we explored the variation in climate conditions and fire-related traits (including tree height, bark thickness, and leaf length) between fire-adapted and non-fire-adapted pines, as well as among three fire survival strategies (fire-tolerators, fire-embracers, fire avoiders). We also investigated the relationships between climatic conditions and fire-related traits/fire-adaptations (including resprouting, self-pruning, the grass stage, and serotiny) across the genus Pinus. Sixty-one out of 101 pine species were found to possess one or more fire adaptations and were classified as fire-adapted pines. We found that fire-adapted pines occupy warmer and more fire-prone habitats, and exhibit longer leaves, thicker bark, and taller habits than non-fire-adapted species. Our analysis did not indicate a significant difference between fire tolerators and embracers regarding traits and climate conditions, except that fire-tolerators have thicker bark and are more associated with wildfire-prone areas. Climate conditions appeared to significantly affect fire-related traits/fire-adaptations across the genus Pinus. These findings will facilitate our understanding the evolutionary process of fire adaptations/fire-related traits in the genus Pinus and will guide sustainable fire management in different pine forests.

Fulvia fulva and Dothistroma septosporum are closely related apoplastic pathogens with similar lifestyles but different hosts: F. fulva is a pathogen of tomato, whilst D. septosporum is a pathogen of pine trees. In 2012, the first genome sequences of these pathogens were published, with F. fulva and D. septosporum having highly fragmented and near-complete assemblies, respectively. Since then, significant advances have been made in unravelling their genome architectures. For instance, the genome of F. fulva has now been assembled into 14 chromosomes, 13 of which have synteny with the 14 chromosomes of D. septosporum, suggesting these pathogens are even more closely related than originally thought. Considerable advances have also been made in the identification and functional characterization of virulence factors (e.g., effector proteins and secondary metabolites) from these pathogens, thereby providing new insights into how they promote host colonization or activate plant defence responses. For example, it has now been established that effector proteins from both F. fulva and D. septosporum interact with cell-surface immune receptors and co-receptors to activate the plant immune system. Progress has also been made in understanding how F. fulva and D. septosporum have evolved with their host plants, whilst intensive research into pandemics of Dothistroma needle blight in the Northern Hemisphere has shed light on the origins, migration, and genetic diversity of the global D. septosporum population. In this review, we specifically summarize advances made in our understanding of the F. fulva-tomato and D. septosporum-pine pathosystems over the last 10 years.

Abstract Key message The invasive pine wood nematode is a major threat to pine forests worldwide, causing extensive tree mortality. Although scientific knowledge and control measures are continuously improving, important gaps remain. We argue that some key questions, notably related to early detection and pest management, need to be urgently tackled in countries at risk of invasion such as France.

The EFSA Panel on Plant Health performed a pest categorisation of Shirahoshizo patruelis (Voss, 1937) (Coleoptera: Curculionidae), following the commodity risk assessment of bonsai plants from China consisting of Pinus parviflora grafted on P. thunbergii, in which S. patruelis was identified as a pest of possible concern to the European Union (EU). This categorisation refers to S. flavonotatus, which is the pest's current valid scientific name. It is native to China and has never been recorded in the EU. It completes from 2 to 3 generations per year. Eggs are laid in cracks and crevices of trunks and branches with bark thickness of approximately 0.6–1.2 cm. The pest overwinters as an adult or as a mature larva under the bark. Plants for planting, wood with bark and wood products provide pathways for entry. Although the weevil has been reported to carry the nematode Bursaphelenchus xylophilus, it is not considered a vector. Climatic conditions and availability of host plants in some EU countries would allow S. flavonotatus to establish and spread. Impact on Pinus spp. is anticipated. Recognising that the weevil is reported to attack both weakened and healthy trees, there is uncertainty on the magnitude of impact. Its recorded capacity to attack non‐Asian Pinus species also indicates its ability to adapt and expand the range of trees it can utilise as hosts, which could include European Pinus species. Phytosanitary measures are available to reduce the likelihood of entry and spread. S. flavonotatus meets the criteria that are within the remit of EFSA to assess for this species to be regarded as a potential Union quarantine pest. [ABSTRACT FROM AUTHOR]

Climate change has caused fluctuations in the frequency and severity of droughts, favoring extended periods of drought associated with anthropic actions and triggering other stressful abiotic effects that threaten terrestrial ecosystems. As climate warming intensifies, drought is a major challenge for forest growth. Pine (Pinus Linn. ) is an important genus of forest in the Northern Hemisphere and has a certain tolerance to drought. This article analyzes and reviews the advances in research about drought stress of major Pinus spp. plants in recent years and discusses understanding and future core problems. To adapt to water-deficient environments, pine plants adapt to drought by changing growth traits, closing some stomata on leaves, changing the growth and structure of roots, and adjusting their physiological activities. Moreover, the expression of specific genes is altered, causing changes in the expression of several signaling molecules and metabolites to counteract drought stress. [ABSTRACT FROM AUTHOR]

Key message: The invasive pine wood nematode is a major threat to pine forests worldwide, causing extensive tree mortality. Although scientific knowledge and control measures are continuously improving, important gaps remain. We argue that some key questions, notably related to early detection and pest management, need to be urgently tackled in countries at risk of invasion such as France. [ABSTRACT FROM AUTHOR]

The EFSA Panel on Plant Health performed a pest categorisation of Dendrolimus punctatus (Lepidoptera: Lasiocampidae), following a commodity risk assessment of bonsai Pinus parviflora grafted onto P. thunbergii from China, in which D. punctatus was identified as a pest of possible concern to the European Union (EU). D. punctatus, also known as the Masson pine caterpillar, is present in China, Taiwan, Vietnam, India and has recently spread to Japanese islands close to Taiwan. Larval feeding on the needles of Pinus elliottii, P. luchuensis, P. massoniana, P. merkusii and P. tabulaeformis causes important damage. D. punctatus larvae can also feed on P. armandii, P. echinata, P. latteri, P. parviflora, P. sylvestris var. mongolica, P. taeda, P. taiwanensis and P. thunbergii, but full development on these hosts is uncertain. The pest has three to five generations per year; winter is spent as larvae on branch tips, on tree trunks and in the soil. The females lay egg clusters on pine needles. Pupation occurs in cocoons attached to branches or needles. D. punctatus could enter the EU either as eggs, larvae or pupae in the foliage of plants for planting or cut branches, as larvae on wood with bark or as overwintering larvae in branches, crevices in the bark or in the litter of potted plants. However, Annex VI of 2019/2072 prohibits the introduction of D. punctatus hosts (Pinus spp.) from countries and areas where the pest occurs. There are climate zones where the pest occurs in Asia that also occur in the EU, though they are limited, which constitutes an uncertainty regarding establishment. The pest's main hosts are not grown in the EU. However, the fact that it attacks the North American Pinus echinata, P. elliottii and P. taeda in its Asian native area suggests a potential capacity to shift to pine species occurring in the EU territory. D. punctatus satisfies all the criteria that are within the remit of EFSA to assess for it to be regarded as a potential Union quarantine pest. Whether the Pinus commonly found in Europe could act as hosts is unknown but is fundamental, affecting the criteria of establishment and magnitude of impact. [ABSTRACT FROM AUTHOR]

Mycorrhizal associations of trees play a key role in ecosystem biogeochemistry, yet we know relatively little about the nutrient acquisition strategies of ericoid mycorrhizal (ErM) shrubs, despite their prevalence in forest understories. ErM shrubs tend to produce litter with high concentrations of polyphenols, which form decay‐resistant complexes with organic nitrogen (N). Some ErM fungi appear capable of producing a diverse suite of extracellular enzymes, but it is unclear whether this enables ErM shrubs to acquire the N from their own litter, and whether this ability is greater than that of ectomycorrhizal (EcM) trees, with which they commonly co‐occur. Here, we conducted two growth chamber experiments with 15N‐enriched root and leaf litters to determine whether EcM pine and ErM vaccinium differ in litter N acquisition from these sources. Grown individually, pine and vaccinium plants acquired 1 mg or 4% of the litter N after one year. Differences between pine and vaccinium in litter N acquisition were correlated with litter chemistry, where vaccinium acquired more N from litter with a high concentration of tannins and a high C:N, while pine acquired more N from litter with a high acid‐insoluble fraction. When plants were grown in pairs, the presence of a vaccinium neighbor reduced the biomass of both species by an average of 24%, but it only reduced litter N acquisition by pine (55%), demonstrating vaccinium's ability to compete with pine for litter N. Regardless of the competitive context, vaccinium allocated a greater percentage (76%) of its acquired litter N to aboveground biomass compared with pine (47%), suggesting vaccinium is more efficient at allocating this N to photosynthesis and growth. Our finding that EcM pine and ErM vaccinium have varying abilities to acquire N from these common litters suggests a degree of niche complementarity, which may facilitate the coexistence of these plants in forest ecosystems. However, our results also suggest that, at high densities, ErM vaccinium has the potential to suppress the growth and N acquisition of EcM pine. Distinct strategies of EcM trees and ErM shrubs for acquiring and using N have the potential to shape biogeochemical cycles of many forested ecosystems. [ABSTRACT FROM AUTHOR]

With a widespread distribution throughout the Northern Hemisphere and 11 genera, Pinaceae is the largest family of Gymnosperms in the world. Essential oils are an important chemotaxonomic marker for the species of this family, although the degree of chemical and biological investigation has not been the same for all genera. Essential oils from Abies and Cedrus (from the abietoid clade) or Pinus and Picea (from the pinoid clade) have been more extensively investigated with respect to their chemical composition and biological or pharmacological properties, including their antioxidant effects. Instead, essential oils from the other genera of the family have been less explored in this respect or even have not been investigated at all. This is a narrative review looking into the knowledge acquired up to date, the variability and limitations of the current methods used to estimate antioxidant effects, and multiple comparisons between EOs obtained from different genera, species, and plant parts, as well as potential applications and future directions of research and utilization of essential oils derived from Pinaceae species. [ABSTRACT FROM AUTHOR]

When controlling the process of improving the quality of seeds by separating on a spectrometric basis, the primary information about the state of Scots pine seeds is carried by the wavelengths of optical fluxes and their amplitudes. The algorithm for analyzing the required characteristics of small forest seeds in the infrared range is a corresponding sequence of logical terms that provide the ability to determine the specified seed parameters by a combination of spectral frequencies and light flux amplitudes taken from the corresponding photodetectors. At ΔС = 0.5, the efficiency of the algorithm was 77.6 %, and at ΔС = 0.9, respectively, 99.5 %. In this regard, the choice of ΔС is the result of a compromise between the cost of rejection of high-quality seeds and losses when using unrecognized low-quality seeds and it is made according to the results of relevant experiments.

Mexico is a center of diversity for the genus Pinus, with 44% of pine species being endemic to the country. Mexican pine forests are recognized as hotspots for ectomycorrhizal fungi and bacteria due to the extensive interactions that take place between microorganisms and plants in their roots. These microorganisms play a vital role in the survival of pine species. This study aims to identify fungal and bacterial communities in a relict Mexican pine forest and evaluate the influence of soil physicochemical parameters on microbial composition. Sampling was conducted along a 145 m transect in an isolated natural relict of P. pseudostrobus var. coatepecensis, which is located within a commercial plantation of Pinus patula. A total of 18 soil samples were collected at predetermined distances along the transect, with replicated sampling points as follows: six samples at 20 cm intervals, four samples at 1 m intervals, four samples at 10 m intervals, and four samples at 25 m intervals. The results indicate that fungal composition varies even at short distances and is influenced by the C:N ratio, total carbon (C), total phosphorus (P), and total hydrogen ion concentration (H+). Ectomycorrhizal fungi (EcM) exhibited a higher relative abundance compared to saprotrophic and pathogenic fungi. A total of 69 EcM ASVs (Amplicon Sequence Variants) were identified, being the dominant genera Tomentella, Clavulina, Suillus, Russula, and Elaphomyces. Bacterial communities did not show significant variation in relation to the distance from the sampling points, but soil pH was identified as the main factor of bacterial composition. Dominant bacterial genera included Burkholderia, Bryobacter, Acidobacterium, and Acidothermus. Additionally, it was observed that current soil conditions influenced β diversity. Overall, the results demonstrate that soil fungal and bacterial communities associated with P. pseudostrobus exhibit a unique composition compared to other natural forest systems in the Neotropics.

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]

Fast-growing wood plantations have been widely used as an alternative to the suppression of native vegetation. Forest wood can be enhanced by thermal modifications, which improve the wood's natural durability and dimensional stability. In addition, the wood's appearance is also enhanced, as its color is made darker, thus more similar to those of tropical woods, which increases its commercial value. However, such heat treatment needs precise process control tools, since it improves the physical properties of wood but reduces its mechanical resistance. Therefore, the use of artificial intelligence, as an artificial neural network (ANN), to conduct the thermal process, can be an alternative to overcome the laborious and detailed work needed to perform the treatment. The purpose of this research was to evaluate the physical, mechanical, and colorimetric properties of the ANN-assisted thermally modified woods of Eucalyptus urophylla and Pinus oocarpa, in order to predict their structural and esthetic properties. The thermal modification improved the physical properties but reduced the mechanical strength of the wood, from 150 ºC and above. Such treatment also promoted color changes. The ANN showed high precision in evaluating and monitoring the properties of the thermally modified woods, with a correlation coefficient for validation higher than 91%, coefficient of determination above 83%, and mean absolute percentage error below 12%. Furthermore, the root mean squared errors and mean absolute percentage error were lower than 13% for all evaluated parameters, showing high accuracy and normal distribution of errors. Therefore, ANN seems a promising alternative for the classification and characterization of thermally modified wood and can be implemented for final quality control of the product. [ABSTRACT FROM AUTHOR]

Copyright of Ecosistemas y Recursos Agropecuarios is the property of Universidad Juarez Autonoma de Tabasco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Betula and Pinus pollen, which are dispersed in natural surface waters, release biologically active compounds into the water bodies. This study aims to evaluate variations in the distribution and composition of phenolic compounds in suspended particles in natural water bodies during pollen spreading. Samples taken from water bodies of different trophic levels were analyzed by microscopy, UV/VIS spectroscopy, HPTLC, and HPLC/DAD. The study revealed that the total phenolic content in water-suspended particles varied from 3.0 mg/g to 11.0 mg/g during Betula and Pinus pollen spreading. It was also observed that the surface water of dystrophic natural lakes had a higher content of phenolic compounds than the eutrophic, hypereutrophic, and mesotrophic water bodies. Chlorogenic, trans-ferulic, vanillin, and 3,4-dihydroxybenzoic acids were frequently detected in the surface water samples. Experimental measurements have shown variations in the release of phenolic compounds from Betula pollen into water (p < 0.05). After the exhibition of pollen, the distilled water predominantly contained bioactive chlorogenic acid. Further in situ investigations are necessary to gain a more comprehensive understanding of the function of phenolic compounds in aquatic ecosystems. The exploration of the release of bioactive compounds from pollen could provide valuable insights into the potential nutritional value of pollen as a nutrient source for aquaculture. [ABSTRACT FROM AUTHOR]

Copyright of Fire Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biological invasions of plants have profound effects on ecosystem functioning by directly and indirectly altering soil microbiota, especially when invasive plants co‐invade with their associated microbiomes. Ecosystem functions may recover slowly following invader removal, with implications for restoration.We investigated the recovery of soil ecosystem function (measured as soil enzymes) following the removal, at different densities and times, of invasive Pinus spp. in New Zealand, and how different enzymatic activities responded to pine legacies.Enzymatic activities were driven by pine legacies via both abiotic (soil nutrients) and biotic (fungi and bacteria) soil properties, with different enzymes showing distinct patterns. The activity of the enzymes cellobiohydrolase (cellulose degrading), β‐glucosidase (cellulose degrading), N‐acetyl‐glucosaminidase (chitin degrading), laccase (lignin oxidising) and acid phosphatase (organic phosphate hydrolysing) were influenced by time since pine removal and by pine density at removal via effects on biotic communities. In comparison, Mn‐peroxidase (lignin oxidising) was positively correlated with density of pines at removal and was negatively correlated with time since removal and was only influenced by fungal communities.Synthesis. The recovery of soil enzymatic function following invasive species removal is slow and dependent on pine legacies through the gradual changes in fungal and bacterial communities. The cascading effects of these changes suggest potential implications for the success of future plant establishment and restoration of co‐invaded ecosystems. [ABSTRACT FROM AUTHOR]

1. Niche theory, neutral theory, and more recently the unifying theory of biodiversity offer alternative views of the structure (or not) of ecological communities. The relative importance of these theories has not been so thoroughly used to explain community assembly processes in phytophagous insects. 2. We studied the mechanisms of community assembly in pine trees phloem feeders, exploring the relative contributions of deterministic and stochastic processes. 3. Temporal and spatial partitioning of wood borers and bark beetles belonging to the pine phloem feeding gild, was assessed through flight traps and pine bolts extracted from felled live Pinus pinaster trees presenting evidence of decline/wilting. 4. We found that deterministic factors explained most cases of coexistence between species, with partitioning in space and time reducing asymmetric competition for resources and intraguild predation, mediated by differences in size. However, in the case of very closely related species with minimum differences in size—in this case three species of Arhopalus—they occupied the same niche in space and time, suggesting that stochastic processes are more likely to maintain co‐occurrence. 5. The present work indicates that both niche and stochastic processes contribute to the assembly of the phloem feeding community. This could be one more example of accordance with the unifying theory of biodiversity. [ABSTRACT FROM AUTHOR]

The conservation of genetic diversity is a crucial aspect of forest tree breeding programs, necessitating strategies for its safeguard. Here, the extent of genetic diversity was assessed in 260 Chinese pine (Pinus tabuliformis Carr.) germplasm samples from five provenances using 24 SSR markers. We systematically compared various methods for constructing a core collection aimed at conserving genetic diversity and the results revealed substantial genetic diversity within this germplasm collection. Extensive gene exchange was observed among four of the sampled five provenances which resulted in forming two genetically distinctive groups. To construct the core collection, six different sampling strategies (PowerCore, Power marker_allele number, Power marker_gene entropy, Power marker_gene diversity, Corehunter, and genetic distance-based) and five different sampling sizes (ranging from 10 to 30%) were employed. Comparative analysis of genetic diversity parameters was conducted across the identified 26 subsets, utilizing the PowerCore strategy as the primary approach for capturing all allelic variation present in the core collection, which consisted of only 61 individuals. A supplementary collection of 20 individuals with high genetic variation was identified to provide a final core collection of 81 individuals, representing 31.2% of the initial collection. The constructed core collection effectively captured the genetic diversity present in the initial collection and serves as a valuable resource for preserving genetic richness within the breeding population. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract The EFSA Panel on Plant Health performed a pest categorisation of Shirahoshizo patruelis (Voss, 1937) (Coleoptera: Curculionidae), following the commodity risk assessment of bonsai plants from China consisting of Pinus parviflora grafted on P. thunbergii, in which S. patruelis was identified as a pest of possible concern to the European Union (EU). This categorisation refers to S. flavonotatus, which is the pest's current valid scientific name. It is native to China and has never been recorded in the EU. It completes from 2 to 3 generations per year. Eggs are laid in cracks and crevices of trunks and branches with bark thickness of approximately 0.6–1.2 cm. The pest overwinters as an adult or as a mature larva under the bark. Plants for planting, wood with bark and wood products provide pathways for entry. Although the weevil has been reported to carry the nematode Bursaphelenchus xylophilus, it is not considered a vector. Climatic conditions and availability of host plants in some EU countries would allow S. flavonotatus to establish and spread. Impact on Pinus spp. is anticipated. Recognising that the weevil is reported to attack both weakened and healthy trees, there is uncertainty on the magnitude of impact. Its recorded capacity to attack non‐Asian Pinus species also indicates its ability to adapt and expand the range of trees it can utilise as hosts, which could include European Pinus species. Phytosanitary measures are available to reduce the likelihood of entry and spread. S. flavonotatus meets the criteria that are within the remit of EFSA to assess for this species to be regarded as a potential Union quarantine pest.

Antecedentes: La información sobre las comunidades templadas es insuficiente, y esto se manifiesta de manera particular en el estado de Michoacán. Preguntas: ¿Cómo está constituido un ecosistema templado establecido en el Cinturón Volcánico Transmexicano (CVTM) en relación con su composición, estructura y diversidad? Sitio y años de estudio: El análisis se llevó a cabo en el otoño e inverno del 2018 en el Parque Nacional Barranca del Cupatitzio en Uruapan, Michoacán, México. Métodos: En 18 parcelas de 0.1 ha (20 × 50 m) se registraron plantas leñosas con un diámetro a la altura de 1.3 m (DAP) ≥ 2.5 cm y se registró el número de individuos y tallos, área basal, cobertura de copa, altura total, la diversidad alfa y se agruparon las unidades con técnicas multivariadas. Resultados: En 1.8 ha se registraron 55 especies, en 42 géneros y 32 familias. Pinaceae fue la más diversa (8) seguida de Asteraceae (9). La densidad (500-1,330 ind. ha-1), los tallos (650-3,040 ind. ha-1), la cobertura (10,999-4,6390 m2ha-1), el DAP (9.2-18.9 cm), la altura (6.5-12 m) y la riqueza (6-17) varían entre parcelas. El 75 % del área basal (20.1 m2 ha-1) fue aportada por los pinos, los encinos contribuyeron con el 14 % (3.6 m2 ha-1) y el 11 % fue de otras especies (2.9 m2 ha-1). Conclusiones: Los ecosistemas forestales del parque mantienen propiedades ecológicas características de los bosques templados del CVTM. Este estudio sirve como punto de referencia para establecer metas de restauración ecológica en el parque explícitamente cuantificables.

The pine processionary moth Thaumetopoea pityocampa is a defoliating lepidopter that develops during winter. The larvae are gregarious and bear urticating setae that are harmful to humans and vertebrates. They shelter in conspicuous silk tents that are easy to detect. We here present a dataset comprising tree characterization and tent counts from 3 agglomerations in France located in regions with different climatic environments. The studied trees belong to various conifer species that are potential hosts for the caterpillars. In each site, we defined clusters as one target tree and its 10–62 nearest neighbors, and surveyed each tree within the clusters by informing: tree species, coordinates, size, number of tents. We characterized a total of 3690 trees, including 2009 trees in Orléans (grouped in 68 clusters), 359 trees in La Baule (18 clusters) and 1322 trees in Montpellier (52 clusters). We provide the raw data characterizing each individual tree, graphs showing the prevalence and mean number of tents for the tree species included in the survey, and maps allowing to locate each tree. This dataset brings information about host preference of the pine processionary moth and will be useful as a baseline to study spatio-temporal variability of host-insect relationships. It can also be informative for decision-makers and managers of urban greenings to avoid trees that are likely to be heavily infested for plantation in proximity to vulnerable people.

Abstract The EFSA Panel on Plant Health performed a pest categorisation of Dendrolimus punctatus (Lepidoptera: Lasiocampidae), following a commodity risk assessment of bonsai Pinus parviflora grafted onto P. thunbergii from China, in which D. punctatus was identified as a pest of possible concern to the European Union (EU). D. punctatus, also known as the Masson pine caterpillar, is present in China, Taiwan, Vietnam, India and has recently spread to Japanese islands close to Taiwan. Larval feeding on the needles of Pinus elliottii, P. luchuensis, P. massoniana, P. merkusii and P. tabulaeformis causes important damage. D. punctatus larvae can also feed on P. armandii, P. echinata, P. latteri, P. parviflora, P. sylvestris var. mongolica, P. taeda, P. taiwanensis and P. thunbergii, but full development on these hosts is uncertain. The pest has three to five generations per year; winter is spent as larvae on branch tips, on tree trunks and in the soil. The females lay egg clusters on pine needles. Pupation occurs in cocoons attached to branches or needles. D. punctatus could enter the EU either as eggs, larvae or pupae in the foliage of plants for planting or cut branches, as larvae on wood with bark or as overwintering larvae in branches, crevices in the bark or in the litter of potted plants. However, Annex VI of 2019/2072 prohibits the introduction of D. punctatus hosts (Pinus spp.) from countries and areas where the pest occurs. There are climate zones where the pest occurs in Asia that also occur in the EU, though they are limited, which constitutes an uncertainty regarding establishment. The pest's main hosts are not grown in the EU. However, the fact that it attacks the North American Pinus echinata, P. elliottii and P. taeda in its Asian native area suggests a potential capacity to shift to pine species occurring in the EU territory. D. punctatus satisfies all the criteria that are within the remit of EFSA to assess for it to be regarded as a potential Union quarantine pest. Whether the Pinus commonly found in Europe could act as hosts is unknown but is fundamental, affecting the criteria of establishment and magnitude of impact.

Profiling the host-mycobiota interactions in healthy vs. diseased forest ecosystems helps understand the dynamics of understudied yet increasingly important threats to forest health that are emerging due to climate change. We analyzed the structural and functional changes of the mycobiota and the responses of Pinus contorta in the Lophodermella needle cast pathosystem through metabarcoding and metatranscriptomics. When needles transitioned from asymptomatic to symptomatic, dysbiosis of the mycobiota occurred, but with an enrichment of Lophodermella pathogens. Many pathogenicity-related genes were highly expressed by the mycobiota at the necrotrophic phase, showing an active pathogen response that are absent in asymptomatic needles. This study also revealed that Lophodermella spp. are members of a healthy needle mycobiota that have latent lifestyles suggesting that other pine needle pathogens may have similar biology. Interestingly, Pinus contorta upregulated defense genes in healthy needles, indicating response to fungal recognition, while a variety of biotic and abiotic stresses genes were activated in diseased needles. Further investigation to elucidate the possible antagonistic interplay of other biotic members leading to disease progression and/or suppression is warranted. This study provides insights into microbial interactions in non-model pathosystems and contributes to the development of new forest management strategies against emerging latent pathogens.

Pinus is an economically and ecologically important genus whose members are dominant components globally in low-latitude mountainous and mid-latitude temperate forests. Pinus species richness is currently concentrated in subtropical mid-low latitudes of the Northern Hemisphere, differing from the latitudinal diversity gradient mostly recognized in woody angiosperms. How the present pattern was developing in Earth's past is still poorly studied, particularly in eastern Asia. Here, a new fossil species, Pinus shengxianica sp. nov. is described based on a fossil seed cone from the Late Miocene Shengxian Formation in Zhejiang, southeast China. A co-occurring cone is recognized as a known fossil species, Pinus speciosa Li. Extensive comparison of extant and fossil members of Pinus suggests P. shengxianica shares a striking cone similarity to Pinus merkusii and Pinus latteri (subsection Pinus) from tropical Southeast Asia in having annular bulges around the umbo on the apophysis. The morphological resemblance indicates these two extant low-latitude pines probably possess a close affinity with the present newly-discovered P. shengxianica and originated from East Asian mid-low latitude ancestors during this generic re-diversification in the Miocene. This scenario is consistent with the evolutionary trajectory reflected by the pine fossil history and molecular data, marking the Miocene as a key period for the origin and evolution of most extant pines globally. The co-occurrences of diverse conifers and broadleaved angiosperms preferring diverse niches demonstrate Late Miocene eastern Zhejiang was one of the hot spots for coniferophyte diversity and hosted a needled-broadleaved mixed forest with complex vegetation structure and an altitudinal zonation.

Resumo O objetivo do trabalho foi avaliar o potencial das cascas de Pinus caribaea var. bahamensis, Pinus caribaea var. caribaea, Pinus caribaea var. hondurensis e Pinus oocarp como fonte para extração de taninos. Os taninos das cascas foram extraídas com água pura e com água e sais sulfito de sódio (Na2SO3) e carbonato de sódio (Na2CO3), nas concentrações de 2% e 5 %. Para as espécies P. caribaea var. bahamensis e P. oocarpa, a adição de 5% de Na2SO3 ou Na2CO3 possibilitou maiores rendimentos em taninos do que a adição de 2%. A casca de P. oocarpa apresentou o maior potencial para obtenção de taninos.

Baishanzu area in Qingyuan, Zhejiang Province, which is famous for the discovery of Abies beshanzuensis, has the most typical mid-subtropical evergreen broad-leaved forest and complete vertical zones of mountain ecosystems in China, and this provides good natural conditions for paleoclimatic reconstruction using surface soil and airborne pollen data. Based on the pollen spectra of nine surface soil pollen samples collected at 300-1,700 m altitude, the relationship between vegetation and surface soil pollen in this area was preliminarily studied. The results show that surface soil pollen in this area can be divided into three assemblage zones from top to bottom according to altitude and ratios of coniferous pollen/broad-leaved pollen and arboreal pollen/non-arboreal pollen, which correspond to the evergreen deciduous broad-leaved mixed forest and temperate coniferous forest, evergreen broad-leaved forest and warm coniferous forest, secondary forest, and farmland (caused by human interference) zones. The surface pollen assemblages were dominated by the evergreen coniferous tree species Pinus, with an average pollen content of 67.5%. The pollen of Castanopsis (6.2%), Quercus (3.4%), Betula (1.4%), and Corylus (1.4%) is common. In contrast, Cyclobalanopsis, Liquidambar, Symplocos, Tsuga, Oleaceae, and Ericaceae had lower contents. Herbaceous plants are dominated by Poaceae (11.2%), including Artemisia, Chenopodiaceae, Apiaceae, Asteraceae, etc. The spore content of fern vegetation was high, mainly Hicriopteris (38.2%) and Polypodiaceae (7.4%). Pinus pollen appeared in all samples, with the highest average content. With increasing altitude, the mean percentage gradually increased from 54.8% to 77.3%, and it is an overly represented pollen with a low sedimentation rate that is easily preserved and transported to the area. Abies pollen is only observed in the samples under the A. beshanzuensis tree at an altitude of 1,700 m. Its percentage is lower than 1%, which may be related to low pollen yield and the relatively narrow distribution range of A. beshanzuensis in this area. In addition, the pollen diversity analysis results based on Simpson's index show that human interference factors prevent the surface soil pollen at lower altitudes in this area from reflecting the regional zonal vegetation. With decreasing altitude, the deciduous component of arboreal pollen in the pollen assemblage increased from 13.2% in Zone I to 40.9% in Zone III. Zone III shows a coniferous and broad-leaved mixed forest zone caused by human factors. The content of the evergreen component in zone I is high, which is related to the high humidity at higher altitudes. This study selects Baishanzu National Park to study the surface soil pollen and preliminarily discusses the characteristics of the surface soil pollen assemblage and its relationship with vegetation, which provide research materials and the basis for Quaternary paleovegetation and paleoclimate reconstructions in the Baishanzu area, Qingyuan County, China. However, due to a lack of surface soil samples and modern vegetation investigation data, the reliability of the research results is affected. In future research, sampling and density quadrat surveys of surface sampling sites will be increased to cover as many vegetation zones as possible.

The quality of planted forest crops depends significantly on the qualities of the planting stock. Numerous studies have been carried out to find clear seedling quality criteria and work out methods for their quantitative assessment to optimize the cultivation regime. Indicators of planting stock that are available for measurement under nursery conditions are needed to predict the success of forest crop establishment. This paper provides a review of the studies that applied different morphological criteria to evaluate coniferous planting stock quality and different determination methods. The suitability of planting stock quality indicators is determined by the effectiveness of predicting the outplanting survival rate (%) and growth. The key morphometric attributes of planting stock are the linear dimensions and biomass of whole seedlings and their individual organs: root collar diameter (RCD), seedling height (SH), dry mass of needles (NDM), stem (SBDM), roots (RDM), shoot/aboveground part of the seedling (SDM), seedling’s total dry matter (TDM), number of needles (NN). Effective indicators of seedling quality are morphometric indicators of roots: total length (TRL), volume (TRV), dry mass (RDM), number of first- (FOLR N), second- (SOLR N), and third-order (TOLR N) lateral roots, root surface area (TRS). TRL is a fairly reliable indicator of absorbent surface area. To minimize errors in the use of one or two traits, integrated seedling quality indices based on two or more indices have been developed. Widely used indices include: SQ = SH(cm)/RCD(mm); SDM/RDM ratio; Dickson quality index DQI = TDM/ ((SH / RCD) + (SDM / RDM)). RCD was the most suitable parameter to indicate seedling quality for many species due to its higher correlation level with the Dickson quality index. The SH index proved to be an effective indicator for analysis only when used together with RCD. When studying the formation of frost resistance, a number of morphological parameters are used: initiation of needle primordia, size of primordial shoots, cell volume, mitotic index (MI) of terminal primordia. Despite advances in testing planting stock quality and predicting field performance, not a single test is universally applicable for all woody plant species and environmental conditions. According to the target seedling concept, the application of morphometric criteria for assessing seedling quality in forest nurseries is a prerequisite for predicting outplanting success and maximizing the predictability of the outcomes of highproductivity forest crop planting. Acknowledgements: The study was funded by the Russian Science Foundation grant No. 23-26-00192, https://rscf.ru/project/23-26-00192/. For citation: Robonen E.V., Chernobrovkina N.P., Egorova A.V., Zaitseva M.I., Nelaeva K.G. Morphometric Criteria for Assessing the Containerized Conifers Seedlings Quality. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 5, pp. 42–57. (In Russ.). https://doi.org/10.37482/0536-1036-2023-5-42-57

RESUMO O objetivo desta pesquisa foi construir e testar oito vigas com 5,4 metros de comprimento, usando laminas de madeira de pinus spp e Eucalyptus citriodora. Quatro delas foram feitas somente com madeira de pinus, e as demais com madeira de Pinus spp e Eucalyptus citriodora. As camadas foram feitas mais longas pelo uso de emendas biseladas no lado tracionado e emendas de topo no lado comprimido das vigas. Nas vigas de pinus, estas juntas foram feitas simultaneamente à colagem das camadas, dispensando a adesão prévia. Em duas vigas de pinus-eucalipto a colagem das lâminas externa foi feita previamente.As vigas foram carregadas até a ruptura e descritas pelo módulo de ruptura (MOR), módulo de elasticidade (MOE) e o tipo de fratura ocorrida.As médias dos módulos de ruptura do primeiro e segundo grupo foram, respectivamente, 55,6 MPa e 70,7 MPa. As diferenças médias entre o modulo de elasticidade experimental e teórico foram de 4,1% e 3,5 % para vigas de pinus e pinus-eucalipto, respectivamente.Ainclusão da madeira de E. citriodora aumenta o MOE de 11.305 MPa para 18.382 MPa. Das quatro vigas testadas de pinus, duas apresentaram ruptura na emenda da lâmina mais solicitada à tração. Nas vigas de pinus-eucalipto, as lâminas das extremidades, que foram emendadas e coladas separadamente, não apresentaram falha por tração ou compressão. Isto sugere que nestas juntas, a colagem deva ser feita previamente.

RESUMO Este trabalho foi desenvolvido com o objetivo de avaliar a qualidade de compensados estruturais com colagem à base de papel impregnado com resina fenólica - filme fenólico. Foram produzidos compensados compostos de cinco lâminas de Pinus taeda com 2 mm de espessura. Os painéis foram prensados com temperatura de 140ºC e 160ºC; pressão específica de 1,5 e 2,0 Mpa, tempo de prensagem real e acrescidos de 1 e 2 minutos. Os resultados da resistência da linha de cola nos testes seco e de fervura demonstraram que o emprego de temperatura de 160ºC e pressão específica de 2,0 MPa seriam as condições mais adequadas para a prensagem de painéis compensados com filme fenólico. Com o emprego de condições adequadas de prensagem, os compensados produzidos com filme fenólico podem apresentar qualidade de colagem superior em relação aos compensados produzidos com resina fenólica na forma líquida.