Forestry research最新文献

Forest germplasm resources are indispensable resources for ecosystem stability and economic value. However, they are increasingly threatened by environmental changes and human activities and urgently need advanced management methods. Concurrently, traditional management methods are unable to cope with the increasingly complex data in the era of advanced information technology. Therefore, we developed DEFGermplasm (https://defgermplasm.com), a digital platform utilizing Flask framework, Python, MySQL, NGINX, Gunicorn, HTML5, JavaScript, JBrowse, SequenceServer, Seaborn, and Echarts, taking the germplasm resources of pecan, hickory, Chinese fir, and phoebe. The platform integrates genomic, transcriptomic, phenotypic, and physiological data, utilizing user-friendly visualization tools to achieve intuitive data presentation. Gene expression heat maps reveal tissue-specific patterns, interactive phenotypic trait visualizations supporting breeding and trait selection, and cross-species analyses uncovering gene conservation and functional adaptation. For example, the WRINKLED1 transcription factor showed roles across nut-bearing and timber species. Additionally, the platform's sequence alignment and homology search tool facilitate comprehensive exploration of gene families, while genome visualization tools provide detailed insights into genomic structures and regulatory elements. By integrating diverse datasets with intuitive visualization tools, DEFGermplasm enhances forest germplasm research, supporting breeding and conservation initiatives. This study underscores the transformative potential of digital platforms in forest genetics and sustainable resource management.

Plant suspension homogeneous cells are invaluable materials for investigating molecular mechanisms underlying various biological processes. In this study, we established and characterized a doubled haploid cell line from Populus simonii × P. nigra, designated as Qu-1. This cell line exhibited high viability and dispersibility under suspension culture conditions and retained the ability to regenerate into whole plants. K-mer analysis confirmed the homozygous genome of Qu-1, and a chromosome-level genome assembly was subsequently achieved by using PacBio sequencing. Additionally, we established an efficient transient transformation protocol using PEG-mediated protoplasts and a stable Agrobacterium-mediated transformation system for Qu-1. To explore the mutagenesis potential of this cell line, we treated the cell line with ethyl methanesulfonate (EMS) and performed genome resequencing to identify mutation sites. Overall, Qu-1 represents the first poplar cell line with a homozygous genome and is as a powerful tool for molecular biology research in woody plants.

Climate warming has substantially delayed the autumn phenology of trees over recent decades. As the primary focus of previous studies on autumn phenology has been on temperate tree species, the environmental regulation of leaf senescence in subtropical trees under distinct climatic conditions remains poorly understood. To address this gap, using climate chambers, we experimentally examined the effects of air temperature, photoperiod, and soil moisture on leaf senescence and dormancy depth in seedlings of four subtropical tree species. Our results showed that low temperature served as the primary environmental cue driving leaf senescence in all four species, whereas photoperiod and soil moisture had no significant effect on senescence under low-temperature conditions. However, under high-temperature conditions, both drought and short photoperiod accelerated leaf senescence. This suggests that during warm autumns in subtropical regions when the typical senescence trigger (low temperature) is absent, drought and photoperiod are alternative cues to ensure senescence occurs before the onset of winter. Furthermore, we found that leaf senescence and dormancy induction were not closely linked processes. Overall, our experimental results reveal the dominant role of air temperature and its interactions with alternative cues (photoperiod and soil moisture) in regulating autumn leaf senescence in subtropical trees, which challenges the common assumption for a majority of temperate tree species that the primary driver of leaf senescence is short photoperiod. These findings provide valuable insights into the ways trees adapt to subtropical environments.

Gibberellins (GAs) are a class of hormonal regulators, which influence various developmental processes in the life cycle of plants. In woody species, bioactive GAs, whose precursors are synthesized by the action of terpene cyclases and carried in the phloem by long-distance translocation from aerial shoot apex and leaves, are known to be a mobile signal to modulate stem growth. However, little is known about the existence and role of local GA synthesis in stems. Here we provide multiple lines of evidence suggesting the presence of local de novo GA biosynthesis in poplar stems and assess its role in wood development. First, the application of a GA biosynthetic inhibitor to decapitated poplar led to a significant reduction in local GA accumulation in the stem. Second, the correlated expression patterns of GA biosynthetic genes across radial tissues showed the existence of local GA production in the stem. Third, bioactive GA assays in transgenic poplar lines expressing Arabidopsis CPS, which encodes the first enzyme in the GA biosynthetic pathway, further confirmed the occurrence of local GA biosynthesis in the bark and cambial zones, but not in the xylem. Finally, modified local GA biosynthesis in the stem revealed its positive effects on secondary growth during wood formation. Taken together, our results demonstrate the existence of local de novo biosynthesis of GAs in poplar stems that contributes to the regulation of wood development via stimulating cambial activity.

Soil salinity significantly inhibits plant productivity by adversely affecting photosynthesis and growth. Nitraria sibirica, a typical halophyte, exhibits strong salt tolerance. In this study, salt-treated Nitraria sibirica seedlings demonstrated more vigorous growth and a higher photosynthetic rate than untreated control seedlings. Transcriptome analysis revealed that the upregulated differentially expressed genes including ribose 5-phosphate isomerase A, ribulose-bisphosphate carboxylase large chain, and malate dehydrogenase in the leaves of Nitraria sibirica treated with 500 mM NaCl were significantly enriched in the 'Carbon fixation in photosynthetic organisms' pathway according to the Kyoto Encyclopedia of Genes and Genomes database. The promoters of these three photosynthetic differentially expressed genes were predicted to contain cis-regulatory elements responsive to light, abscisic acid, and ethylene. Notably, genes encoding 1-aminocyclopropane-1-carboxylate synthase, a key enzyme in ethylene biosynthesis, and ethylene-responsive transcription factors were significantly upregulated in Nitraria sibirica under 500 mM NaCl treatment. Furthermore, quantitative real-time PCR analysis confirmed that the expression of these differentially expressed genes was significantly upregulated in Nitraria sibirica leaves treated with 500 mM NaCl and 500 mM ethephon for 1 h. In contrast, the expression of these salt-induced differentially expressed genes was significantly downregulated in Nitraria sibirica leaves treated with 500 μM aminoethoxyvinylglycine, an ethylene biosynthesis inhibitor, in combination with 500 mM NaCl for 1 h. These findings suggest that the enhanced photosynthesis observed in Nitraria sibirica under salt stress is likely mediated by ethylene signaling, which regulates the expression of genes involved in carbon fixation, thereby promoting vigorous plant growth.

Global change drivers, including drought and nitrogen (N) deposition, exert a wide-ranging influence on tree growth and fitness. However, our current understanding of their combined effects is still limited. Non-structural carbohydrate (NSC) storage is an important physiological trait for tree acclimation to drought. It acts as an important mobile carbon reserve to support tree function when carbon fixation or transport are reduced under drought. It is crucial to investigate how tree species with different NSC storage characteristics (e.g., storage level, partitioning) respond to drought events, and how N alters these patterns. We investigated the combined effects of drought (80% reduction in precipitation) and N addition (0, 30, and 120 kg/ha/year) on the growth and NSC storage of Pinus koraiensis and Fraxinus mandshurica (dominant species in the forests of Northeast China) saplings over two consecutive growing seasons. The results indicated that P. koraiensis exhibited high tolerance to drought, with growth unaffected by drought alone until the mid-growing season in the second year. However, N addition reversed its drought acclimation by impairing root development and exacerbating carbon shortage. In contrast, F. mandshurica was sensitive to drought, it had significantly reduced growth at harvest despite a large amount of NSC accumulation. The present study highlights the contrasting effects of N deposition on drought adaptation in coexisting conifer and temperate broadleaf species, the conifer showing a higher risk of carbon deficiency with increasing N deposition (i.e., a stronger reversal effect of N addition), whereas an earlier cessation of growth under drought defines a larger carbon safety margin for broadleaved species. These results have important implications for the development of adaptive forest management strategies such as to enhance the protection of conifers in the context of global change.

A key objective of forest tree breeding programs is to enhance traits related to growth and stem form, to cultivate plantations that exhibit rapid growth, straight trunks with minimal taper, and superior wood quality to meet the demands of modern timber production. Notably, Liriodendron species exhibit notable heterosis in interspecies hybrids, with hybrid Liriodendron displaying rapid growth rates, straight trunks, and wide adaptability. However, the genetic architecture underlying growth and stem form traits remains unclear, hindering the progress of genetic improvement efforts. Genome-wide association study (GWAS) emerges as an effective approach for identifying target genes and clarifying genetic architectures. In this study, a comprehensive analysis was conducted using an artificial population of 233 hybrid progeny derived from 25 hybrid combinations and resequenced to obtain genome-wide single nucleotide polymorphism (SNP) and insertion and deletion (InDel) variants. After filtering, a total of 192,972 SNP loci and 60,666 InDel loci were obtained, which were subsequently analyzed for associations using the R package GAPIT. We identified 97 significant SNP loci and 58 significant InDel loci (-Log₁₀(P) ≥ 4.50), respectively, culminating in the identification of 161 candidate genes. The functions of these candidate genes were annotated, revealing potential associations between Lchi_2g03172 and Lchi_10g19986 genes with the growth of hybrid Liriodendron, and highlighting the potential influence of the Lchi_16g30522 gene on the growth and branching of hybrid Liriodendron. Overall, this study serves as a foundational step towards unraveling the genetic architecture underpinning growth and stem form in Liriodendron plants.

Understanding genotype, environment, and genotype-by-environment (G × E) interactions is vital for effective forest breeding. The Catalpa bungei, valued for its rapid growth and high-quality wood, exhibits uncertain genetic variation in growth across diverse ecological conditions. To clarify this, we measured the growth traits of clones over several years at multiple sites to evaluate the effects of genetics and environment on growth. The results indicate that growth traits exhibit significant genetic differences and high repeatability, and the significant G × E interaction highlights the importance of site-specific tree selection. Correlation and regression analysis indicated that MCMT was positively correlated with DBH, whereas DD < 18 was negatively correlated with DBH. TD and CMD showed positive correlations with height and volume. Multivariate regression trees (MRT) analysis showed that clones thrived under specific conditions: TD > 26.65 °C with MCMT > 0.1 °C and CMD > 520.5. Mantel analysis results indicated that TD is the main factor driving the G × E of DBH. To identify clones well-suited for targeted cultivation and stability in various regions, we estimated BLUP values for clone growth and applied BLUP-GGE to assess the yield and stability of 5-year height, 9-year DBH, and 5-year volume. Clone 1-1 was selected for its high and stable DBH, with a 6.22% genetic gain. Clone 22-03 was selected for its high and stable volume, with a 12.11% gain. These elite clones are anticipated to boost C. bungei plantation productivity and are likely to be cultivated and promoted across multiple regions.

The xyloglucan endotransglycosylase/hydrolase (XTH) gene family plays a crucial role in plant cell wall remodeling, facilitating growth and structural changes. However, the divergence of paralogous genes among different species of Populus remains inadequately understood. This study investigates the phylogenetic relationships and expression characteristics of XTH genes in two Populus species: Populus trichocarpa and Populus alba × P. glandulosa '84K'. Forty-one XTHs were identified in P. trichocarpa and 38 and 33 members in the subgenome A and G of '84K' poplar, respectively. Gene expression analysis demonstrated differences among paralogous genes within the same subgenome and between orthologous genes across species, likely influenced by variations in promoter regions. Notably, XTH12 showed a specific response to drought stress among various abiotic stresses. In a population of 549 Populus individuals, functional SNPs in XTH12's coding region did not affect its conserved ExDxE catalytic site, highlighting its irreplaceable function. Furthermore, validation through qRT-PCR and ProPagXTH12::GUS activity, alongside PagXTH12-overexpression poplar lines, substantiated the role of PagXTH12 in modulating the balance between plant biomass and drought resistance. Overall, this research provides valuable insights into the biological functions of XTHs in plant environmental adaptability and offers strategies for targeted regulation of tree growth and stress resistance.

Polyphenols, as one of the primary compounds produced by plant secondary metabolism, have garnered considerable attention because of their non-toxic, environmentally friendly, and biodegradable properties, as well as their notable medicinal value. This study presents a metabolomic analysis of polyphenols from 11 woody plants, including Camellia oleifera, Quercus acutissima, and Punica granatum, investigating a total of 40 polyphenolic metabolites. A differential metabolite dynamics map highlighted the five most differentiated substances among the 11 plants, including vitexin, dihydromyricetin, genistin, resveratrol, and isorhamnetin. To evaluate the application of polyphenol-rich plants as natural dyes, dye performance tests, and color fastness evaluations were conducted, focusing on the specific role of polyphenols in dyeing cotton fabrics. The composition of polyphenols had a minor effect on the color of dyed cotton fabrics, typically imparting only black or brown tones to the fabric. However, their effect on dyeing performance is notable, with the ratio of the dye absorption coefficient (k) to the dye scattering coefficient (s) (K/S) ranging from 1 to 20, and lightness varying from 26 to 78. The addition of mordants not only improved the dye's color fastness but also expanded the color range. Furthermore, this study identified four key substances that influence the dyeing performance of plant dyes, including naringenin, epicatechin, catechin, and dihydromyricetin, and discovered a novel natural dye compound, naringenin. Importantly, six of the 11 plant dyes selected in this study are derived from plant waste, thus providing a theoretical basis for advancing environmentally friendly and sustainable dyeing technologies.