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1.
J Chromatogr A ; 1663: 462737, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-34968956

RESUMO

A non-targeted metabolomics-based approach using liquid chromatography high-resolution mass spectrometry was used to authenticate spruce wood (Picea abies) from two geographic source areas. The two sample sites were located in Germany and only 250 km apart. In order to achieve the highest possible metabolite coverage, the spruces samples were measured with four different methods using liquid chromatography high-resolution mass spectrometry. In this way, a total of approximately 4,100 features were detected, which included non-polar, polar, and intermediate-polar metabolites. Using supervised multivariate methods, a distinction between the two sample groups could be achieved on the basis of non-polar data sets. The major metabolites contributing to differentiation were identified by MS/MS experiments and were from the following classes of compounds: ceramides, fatty acids, glycerolipids, and phytosterols. Based on the soil descriptions of the two sites, it was concluded that there is probably a close relationship between nutrient availability and the differences in concentration of the marker compounds. The results show that a metabolomics-based approach is also suitable for differentiation of origin, even if the sample sites are close to each other.


Assuntos
Abies , Picea , Cromatografia Líquida , Metabolômica , Espectrometria de Massas em Tandem , Madeira
2.
Ying Yong Sheng Tai Xue Bao ; 32(10): 3576-3584, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34676719

RESUMO

Tree-rings of Picea crassifolia from high (3000 m), middle (2750 m) and low (2500 m) altitudes were collected from the Xiying River basin in the eastern Qilian Mountains, with the standard chronology being established using dendrochronological methods. Results of the correlation analysis between tree-ring width index and temperature and precipitation during different periods showed that radial growth of P. crassifolia at different altitudes responded differently to climate warming in the eastern Qilian Mountains. Water and heat availability were the main limiting factors for the radial growth of P. crassifolia in the eastern part of Qilian Mountains. The growth limiting factors at different altitudes were generally the same. Before the prominent warming (1961-1986), radial growth of P. crassifolia at the three sampling altitudes was significantly negatively correlated with mean maximum temperature in July-August of the previous year and August of the current year, and significantly positively correlated with the relative humidity in June of the current year. After the prominent warming period (1986-2014), tree growth at high, middle, and low altitudes remained significantly negatively correlated with air temperature, changed from non-significantly negative to significantly positive correlation with relative humidity in February of the current year, and changed from significantly positive to non-significantly negative correlation with precipitation and relative humidity in June. Warming caused a slowing growth of P. crassifolia tree-ring at all altitudes, with the highest altitude being the most sensitive. Drought stress caused by climate warming might be the main reason for the changes of radial growth of P. crassifolia.


Assuntos
Picea , Altitude , China , Clima , Árvores
3.
Ying Yong Sheng Tai Xue Bao ; 32(10): 3585-3593, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34676720

RESUMO

The radial growth of eight individuals of Picea crassifolia and environmental factors were monitored by Dendrometer and automatic meteorological station in the western Qilian Mountains. The Gompertz function fitted results showed that the radial growth of P. crassifolia started on April 19, April 17, and April 10 in 2018, 2019 and 2020, respectively, and that the radial growth started when daily mean temperature exceeded 5.5 ℃. The radial growth of P. crassifolia ended on August 17, August 21, and July 19 in the three years, respectively. The ending time of radial growth was related to precipitation at the end of growing season. The radial growth of P. crassifolia was strongly inhibited by drought, and it had the strongest correlation with daily mean temperature (negative correlation) and daily precipitation (positive correlation) in July. The correlation of radial growth with the daily precipitation in the early growing season (May) showed significant inter-annual variation.


Assuntos
Picea , China , Secas , Humanos , Estações do Ano , Temperatura , Árvores
4.
Ying Yong Sheng Tai Xue Bao ; 32(10): 3594-3608, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34676721

RESUMO

Based on the standard method of dendrochronology, we examined the tree-ring width index of two dominant tree species in the Altay Mountains, China, including Picea obovata and Larix sibirica. We analyzed the basal area increments (BAI) of those two species and the relationships between their radial growth and the climatic factors, which were compared in similar habitats. The results showed that the BAI of P. obovata was greater than L. sibirica, but the radial growth rate of L. sibirica was greater. In recent 60 years, the radial growth of P. obovata negatively correlated with high temperature in the fast growing stage of previous year, while the high temperature in June of current year promoted the radial growth of L. sibirica. There was a significantly negative correlation between radial growth of L. sibirica with temperature in January of current year. The sensitivity of tree growth to climate showed an obvious increase after an abrupt climate change under the background of recent warming and wetting trend in mid-1980s. Results of the moving correlation analysis showed that the response of the radial growth of P. obovata and L. sibirica to temperature and precipitation were enhanced under the background of climate change in the study area.


Assuntos
Picea , Traqueófitas , China , Mudança Climática , Árvores
5.
Ying Yong Sheng Tai Xue Bao ; 32(10): 3627-3635, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34676724

RESUMO

We constructed standard tree-ring-width chronology of Picea likiangensis var. rubescens for the Larima sampling site in the Ganzi Prefecture, Sichuan Province, by the single-free detren-ding method. The results showed that there was significant and positive correlation between the tree-ring chronology and March-August 1-month scale standardized precipitation and evapotranspiration index (SPEI1) of Yajiang region. The variation of the March-August SPEI1 sequence for 1942-2008 was reconstructed based on the current and last year sequences of the tree-ring chronology, with an explained variation of 42.8%. The newly reconstructed series mainly represented the variation of SPEI1 in the low-frequency domain over the historical period. Three wet periods were found in 1442-1465, 1516-1601 and 1836-2008, while the two intervals were dry periods for the March-August SPEI1 reconstruction in the Yajiang region of West Sichuan Plateau. There was a significant drying trend in 1456-1762 for the reconstructed sequence, a significant wetting trend in 1455-1762, while the wetting trend was the most significant in 1959-2008. Mutation test showed that the sudden changes from dry to wet for the March-August SPEI1 reconstructions occurred in 1512, 1733, 1767, 1831, 1941, 1957 and 1975, while that in 1684 and 1961 was the opposite. The comparison with surrounding region showed a good coherence of variations in the low-frequency domain among the SPEI1 reconstruction for the Yajiang region, the annual precipitation reconstruction for the northeastern Tibetan Plateau, and the SPEI05 reconstruction for the northern slope of the eastern Qilian Mountains. The reconstructed sequence well represented the variation of the March-August SPEI1 in the northeastern Tibetan Plateau and the southern Qinhai Province.


Assuntos
Picea , Árvores , China , Secas
6.
Ying Yong Sheng Tai Xue Bao ; 32(10): 3636-3642, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34676725

RESUMO

Dendroclimatology is one of the important methods for studying climate changes in the past. Previous studies showed that tree-ring density is an important proxy for temperature in the growing season. In this study, we established 132-135 years chronologies of tree-ring maximum density, the minimum density, the latewood and the earlywood average density of Picea crassifolia at the western Qilian Mountains. We compared the climatic signal and its seasonal best combination of different tree-ring density chronologies, and evaluated their potential values as climate proxies. The responses of tree-ring latewood average density and the earlywood average density to climate signals during the growing season were much lower than that of tree-ring maximum and the minimum den-sity. The tree-ring earlywood average density and the minimum density had a strong relationship with the Palmer drought index, indicating that the earlywood average density and the minimum tree-ring density had the potential as substitute indicators for drought.


Assuntos
Picea , China , Secas , Temperatura , Árvores
7.
Ying Yong Sheng Tai Xue Bao ; 32(10): 3671-3679, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34676729

RESUMO

The normalized difference vegetation index (NDVI) is widely used in various fields of vegetation research. Due to the short observation time, however, it is difficult to meet the research needs at long time scale. Here, we established a tree-ring width chronology (STD) based on Picea schrenkiana in Bayinbuluke, and calculated the correlation coefficient of chronology and NDVI with meteorological data. The results showed that both tree-ring width index and NDVI were significantly correlated with meteorological data. Combined with the significant positive correlation between width chronology and NDVI in June-August (r=0.7, P<0.01, n=38), summer NDVI (from June to August) was reconstructed over the past 339 years using a regression model. During 1680-2018, the reconstruction series had four dense vegetation periods (1738-1765, 1786-1798, 1964-1973 and 2000-2018) and five sparse vegetation periods (1690-1714, 1825-1834, 1850-1880, 1895-1920 and 1945-1955). The reconstruction reflected the hydrological signals in the central Tianshan Mountains. The comparison with the surrounding reconstructions revealed that when the runoff of Kaidu River increased and the local environment was humid, the vegetation coverage was high; otherwise the vegetation coverage was low. The extreme value of the reconstruction series also captured a series of natural disasters recorded in historical documents. Results of HYSPLT (Hybrid Single-Particle Lagrangian Integrated Trajectory Model) backward trajectory model and wind field analysis showed that NDVI anomalies were affected by the precipitation from Westerlies.


Assuntos
Picea , Árvores , China , Mudança Climática , Estações do Ano
8.
Ying Yong Sheng Tai Xue Bao ; 32(8): 2745-2754, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34664447

RESUMO

To reveal the community succession rule of natural secondary forest, we investigated basic characteristics and coordinates of each tree (DBH≥1 cm) within a plot (100 m×100 m) using the adjacent grid method and examined the distribution pattern and spatial associations of dead woods in a natural spruce-fir secondary forest in Jingouling Forest Farm, Wangqing Forestry Bureau, Jilin Province, China. The results showed that the diameter class distribution of dead woods showed the pattern of left single-peak curve, while the logs showed the pattern of multi-peak curve. The relationship between the abundance of dead woods and the standing individuals of a particular species was inconsistent. There was a significant negative exponential relationship between the number of dead woods and mixing degree of trees. The distribution of dead woods was concentrated at the 0-8 m scale. With the increases of scale, it gradually changed to random or uniform, with the random distribution being dominant. The aggregation distribution of dead woods with middle (10 cm≤DBH<20 cm) and small (1 cm≤DBH<10 cm) DBH was the main reason for the aggregation distribution of dead woods at small scale below 8 m. The spatial associations between dead woods and stan-ding trees at different diameter classes were significantly different. The relationship between dead woods and saplings (1 cm≤DBH<5 cm) was closely correlated. The dead woods with large DBH and saplings showed a significant positive association at 2-25 m scale. There was no spatial association between dead woods and small trees (5 cm≤DBH<15 cm). At the 0-3 m scale, there was a positive association between the middle trees (15 cm≤DBH<25 cm) and dead woods of small and middle DBH. At the 9, 11-14 and 15, 42-45 m scales, dead woods of small and middle DBH were significantly negatively associated with large trees (DBH≥25 cm). In conclusion, biological traits, diameter class distribution, and spatial distribution affected the abundance and diameter class distribution of dead woods. The species with low mixing degree tended to have more dead woods. The diameter and scale would affect the spatial distribution of dead woods. The spatial correlation between dead woods and standing trees varied across diameter classes and scales.


Assuntos
Florestas , Picea , China , Humanos , Árvores , Madeira
9.
Ying Yong Sheng Tai Xue Bao ; 32(9): 3061-3069, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34658190

RESUMO

Based on the survey data from a 4 hm2 secondary Picea forest plot in the Pangquangou Nature Reserve, Guandi Mountain, Shanxi Province in 2010 and 2015, we analyzed the quantitative characteristics, distribution pattern, and correlation of living and dead standing trees during five years from four aspects, including species composition, diameter class structure, spatial pattern, spatial correlation between different diameter classes of living standing trees and dead standing trees, and intercorrelation between different diameter classes of dead standing trees. The results showed that there were 25811 living standing trees with DBH≥1 cm in the plot in 2010, belonging to 30 species, 22 genera, and 11 families. The distribution of individual diameter class was an inverted "L" type, and the number of individuals decreased in a fracture pattern with the increases of diameter class. During the five years (2010-2015), a total of 2145 dead standing trees were formed, involving 12 species, 10 genera, and 5 families. Most of the dead standing trees were distributed in diameter of 5-10 cm. At the scale of 0-50 m, the spatial distribution of living and dead standing trees was generally similar, indicating that the spatial pattern of dead standing trees was limited by that of living standing trees to some extent. The spatial correlation analysis of each diameter class of dead standing trees and living standing trees showed that with the increases of individual diameter class of trees, the intensified competition for space resources might be the main reason for the generation of dead standing trees. With the increases of diameter class of dead standing trees, the spatial correlation between living and dead standing trees was weakened to varying degrees, indicating that environment might be the key factor for the formation of large diameter class of dead standing trees. For the the dead standing trees, there was an obvious positive correlation between 5 cm≤DBH<20 cm dead standing trees and DBH<5 cm dead standing trees, between 10 cm≤DBH<20 cm dead standing trees and 5 cm≤DBH<10 cm dead standing trees, and between DBH≥20 cm dead standing trees and 5 cm≤DBH<20 cm dead standing trees. Our results indicated that dead standing trees would impact the subsequent dying of living standing trees.


Assuntos
Picea , Árvores , China , Florestas , Humanos , Análise Espacial
10.
Physiol Plant ; 173(4): 2130-2141, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34537962

RESUMO

Ectomycorrhizal (ECM) fungi colonization and function depend on soil water and nutrient supply. To study the effects of resource supply on ECM colonization and inorganic nitrogen (N) uptake by roots of Picea asperata seedlings, we conducted a study at the end of a 5-year long experiment consisting of five watering regimes (40, 50, 60, 80, and 100% of field capacity) and three NH4 NO3 application rates (0 [N0], 20 [N1], and 40 [N2] g N m-2  year-1 ). We measured fluxes of ammonium ( NH 4 + ) and nitrate ( NO 3 - ) into colonized and uncolonized roots using noninvasive microtest technology. We found that, across the N supply levels, ECM colonization rate increased by 53 ± 14% from the highest to the lowest level of water supply. Across the watering regimes, the fraction of mycorrhizal root tips was 39 ± 4% higher under native N supply compared to roots grown under N additions. As expected for conifers, both colonized and uncolonized roots absorbed NH 4 + at a higher rate than NO 3 - . N additions reduced the instantaneous ion uptake rates of uncolonized roots grown under low water supply but enhanced the fluxes into roots grown under sufficient soil water availability. Soil water supply improves inorganic N uptake by uncolonized roots but reduces the efficiency of colonized roots. Under the lowest water supply regime, the uptake rate of NH 4 + and NO 3 - by colonized roots was 40-80% of those by uncolonized roots, decreasing to 20-30% as soil water supply improved. Taken together, our results suggest that the role ectomycorrhizae play in the nutrient acquisition of P. asperata seedling likely diminishes with increasing availability of soil resources.


Assuntos
Micorrizas , Picea , Aclimatação , Nitrogênio , Raízes de Plantas , Solo , Água
11.
Nat Commun ; 12(1): 4941, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34400639

RESUMO

Plant small RNAs are important regulatory elements that fine-tune gene expression and maintain genome integrity by silencing transposons. Reproductive organs of monocots produce abundant phased, small interfering RNAs (phasiRNAs). The 21-nt reproductive phasiRNAs triggered by miR2118 are highly enriched in pre-meiotic anthers, and have been found in multiple eudicot species, in contrast with prior reports of monocot specificity. The 24-nt reproductive phasiRNAs are triggered by miR2275, and are highly enriched during meiosis in many angiosperms. Here, we report the widespread presence of the 21-nt reproductive phasiRNA pathway in eudicots including canonical and non-canonical microRNA (miRNA) triggers of this pathway. In eudicots, these 21-nt phasiRNAs are enriched in pre-meiotic stages, a spatiotemporal distribution consistent with that of monocots and suggesting a role in anther development. Although this pathway is apparently absent in well-studied eudicot families including the Brassicaceae, Solanaceae and Fabaceae, our work in eudicots supports an earlier singular finding in spruce, a gymnosperm, indicating that the pathway of 21-nt reproductive phasiRNAs emerged in seed plants and was lost in some lineages.


Assuntos
Magnoliopsida/metabolismo , Nucleotídeos/metabolismo , RNA de Plantas/genética , RNA Interferente Pequeno/metabolismo , Sementes/metabolismo , Fragaria/genética , Fragaria/metabolismo , Regulação da Expressão Gênica de Plantas , Meiose , MicroRNAs/genética , Filogenia , Picea/genética , Proteínas de Plantas/genética , RNA de Cadeia Dupla/metabolismo , Solanaceae/metabolismo , Transcriptoma
12.
Sci Total Environ ; 794: 148514, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34218146

RESUMO

An increase in frequency, intensity and duration of drought events affects forested ecosystems. Trees react to these changes by adjusting stomatal conductance to maximize the trade-off between carbon gains and water losses. A better understanding of the consequences of these drought-induced physiological adjustments for tree growth could help inferring future productivity potentials of boreal forests. Here, we used samples from a forest inventory network in Canada where a decline in growth rates of black spruce (Picea mariana (Mill.) B.S.P.) and jack pine (Pinus banksiana Lamb.) occurred in 1988-1992, an exceptionally dry period, to verify if this growth decline resulted from physiological adjustments of trees to drought. We measured carbon and oxygen isotope ratios in growth rings of 95 spruces and 49 pines spanning 1985-1993. We used 13C discrimination (Δ13C) and 18O enrichment (Δ18O) as proxies for intrinsic water use efficiency and stomatal conductance, respectively. We studied how inter-annual variability in isotopic signals was linked to climate moisture index, vapor pressure deficit and annual snowfall amount. We found significantly lower Δ13C values over 1988-1990, and significantly higher Δ18O values in 1988-1989 and 1991 compared to the 1985-1993 averages. We also observed that a low climatic water balance and a high vapor pressure deficit were linked with low Δ13C and high Δ18O in the two study species, in parallel with low growth rates. The latter effect persisted into the year following drought for black spruce, but not for jack pine. These findings highlight that small differences in physiological parameters between species could translate into large differences in post-drought recovery. The stronger and longer lasting impact on black spruce compared to jack pine suggests a less efficient carbon use and a lower acclimation potential to future warmer and drier climate conditions.


Assuntos
Picea , Pinus , Canadá , Secas , Ecossistema , Árvores
13.
Vopr Pitan ; 90(3): 110-116, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34264562

RESUMO

For decades, one of the most popular ideas in reducing the burden of cancer worldwide is the idea of cancer chemoprevention with low-toxic agents. There is an evidence that polyprenols (polyisoprenoid alcohols) are perspective agents for cancer chemoprevention. The aim of the study is to investigate anticancer activity of the polyprenol complex (the main polyprenols are prenol-14, prenol-15, prenol-16 and prenol-17) against prostate cancer (PCa) and its precursor (prostatic intraepithelial neoplasia, PIN). Material and methods. For induction of prostate carcinogenesis we used modified protocol of two-stage model. Mature male Wistar rats were administrated with single intravenous injection of N-methyl-N-nitrosourea and chronic intraperitoneal injections of four testosterone esters following surgical castration. Animals with an initial body weight of 328±39 g were randomized into 3 groups: experimental group (n=32) - animals received polyprenols complex 12.5 mg/kg per os diluted in vegetable oil 5 days a week; control group (n=38) - animals received vehicle (vegetable oil) 0.5 ml per os 5 days a week; intact group (n=12) - animals without intervention. Duration of the experiment was 56 weeks. At the end of the study and in euthanized animals in terminal state as well, the prostate and seminal vesicles were processed by histological technique and serial step sections of all lobes were assessed blindly by two independent pathologists. Incidence and multiplicity of precancerous lesion (PIN) and prostate tumors were calculated. Results. Compared with the control group, long-term consumption of polyprenols significantly reduced the overall incidence of PIN from 76.5 to 44.8% (р=0.0183; relative risk, RR=0.59; 95% CI 0.38-0.91), multiplicity of PIN per rat per group by 48.4% (р=0.0081), the incidence of PIN in 2 or 3 lobes of the prostate from 55.9 to 27.6% (р=0.0402), the incidence of PIN in the dorsolateral prostate from 70.6 to 41.4% (р=0.0240), the incidence of PIN in the ventral lobe from 47.1 to 20.7% (р=0.0362). The polyprenol complex exhibited a pronounced anticancer effect against induced prostate tumors. In the group of animals receiving the tested agent, there was a significant decrease in the total incidence of PCa from 64.7 to 34.5% (р=0.0234; RR=0.53; 95% CI 0.30-0.93), as well as the multiplicity of PCa per rat per group and per PIN carrier by 63.4% (р=0.0024) and by 30.6% (р=0.0240) respectively. In the polyprenols group we observed significant decrease in the incidence of prostate cancer in 2 or 3 lobes from 32.4 to 6.9% (р=0.0147) and the incidence of PCa in the dorsolateral prostate from 58.8 to 24.1% (р=0.0101). Oral administration of polyprenols provided a nonsignificant trend towards a decrease in the incidence of metastatic prostate cancer from 32.4 to 20.7% (р=0.3962). Conclusion. Chronic oral consumption of polyprenols from the needles of Picea abies L. and Pinus sylvestris L. (12.5 mg/kg per day) significantly suppresses the development of PIN and PCa induced by MNM and a mixture of testosterone esters in male Wistar rats. Despite the exploratory nature of the study, our results can serve the rationale for further investigation of polyprenols in prostate cancer chemoprevention trials.


Assuntos
Abies , Picea , Pinus sylvestris , Animais , Carcinogênese , Poliprenois , Próstata , Ratos , Ratos Wistar
14.
Sci Total Environ ; 798: 149267, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34332391

RESUMO

Knowledge on the adaptation of trees to rapid environmental changes is essential to preserve forests and their ecosystem services under climate change. Treeline populations are particularly suitable for studying adaptation processes in trees, as environmental stress together with reduced gene flow can enhance local adaptation. We investigated white spruce (Picea glauca) populations in Alaska on one moisture-limited and two cold-limited treeline sites with a paired plot design of one forest and one treeline population each, resulting in six plots. Additionally, one forest plot in the middle of the distribution range complements the study design. We combined spatial, climatic and dendrochronological data with neutral genetic marker of 2203 trees to investigate population genetic structure and drivers of tree growth. We used several individual-based approaches including random slope mixed-effects models to test the influence of genetic similarity and microenvironment on growth performance. A high degree of genetic diversity was found within each of the seven plots associated with high rates of gene flow. We discovered a low genetic differentiation between the three sites which was better explained by geographic distances than by environmental differences, indicating genetic drift as the main driver of population differentiation. Our findings indicated that microenvironmental features had an overall larger influence on growth performances than genetic similarity among individuals. The effects of climate on growth differed between sites but were smaller than the effect of tree size. Overall, our results suggest that the high genetic diversity of white spruce may result in a wider range of phenotypes which enhances the efficiency of selection when the species is facing rapid climatic changes. In addition, the large intra-individual variability in growth responses may indicate the high phenotypic plasticity of white spruce which can buffer short-term environmental changes and, thus, allow enduring the present changing climate conditions.


Assuntos
Picea , Mudança Climática , Ecossistema , Florestas , Humanos , Picea/genética , Árvores
15.
Ying Yong Sheng Tai Xue Bao ; 32(6): 2053-2060, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34212611

RESUMO

We explored the effects of disturbance densities on the spatial pattern and the association of tree species in the coniferous broadleaved mixed forest in Pangquangou Nature Reserve of Guandi Mountain. Using three factors including canopy density, stand density and number of stumps, we classified the disturbance intensities of different forest stands into three levels, non-disturbance, moderate disturbance, and severe disturbance. The spatial distribution pattern and the association of different tree species were analyzed by spatial point pattern K2 function. The results showed that the diameter distribution of trees in undisturbed plots was inverted 'J' type, while that of moderate disturbance and serious disturbance plots was under bimodal curve distribution. The stand distribution pattern showed a small-scale aggregated distribution under undisturbed and moderately distur-bance, and a random distribution under heavy disturbance. At the small scale, the coniferous and broadleaved species showed no correlation in undisturbed stands, were positively correlated in moderately disturbed stands, and negatively correlated in seriously disturbed stands. At large scale, they were no correlated in both moderately and seriously disturbed stands. The results suggested that abundance of trees with small diameter in the forests was negatively with disturbance intensity, which led to the lower degree of intraspecific aggregation at small scale. Meanwhile, appropriate levels of disturbance would benefit the collaborative use of environmental resources for trees. Our results revealed the impacts of disturbance density on forest community structure and could provide theoretical basis for forest management.


Assuntos
Picea , Pinus , Traqueófitas , China , Florestas , Árvores
16.
Mycologia ; 113(5): 891-901, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34236933

RESUMO

Suillus is among the best-known examples of an ectomycorrhizal (ECM) fungal genus that demonstrates a high degree of host specificity. Currently recognized host genera of Suillus include Larix, Pinus, and Pseudotsuga, which all belong to the pinoid clade of the family Pinaceae. Intriguingly, Suillus sporocarps have been sporadically collected in forests in which known hosts from these genera are locally absent. To determine the capacity of Suillus to associate with alternative hosts in both the pinoid and abietoid clades of Pinaceae, we examined the host associations of two Suillus species (S. punctatipes and S. glandulosus) through field-based root tip sampling and seedling bioassays. Root tip collections underneath Suillus sporocarps were molecularly identified (fungi: nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 [ITS barcode]; plant: trnL) to assess the association with multiple hosts. The bioassays contained both single- and two-species treatments, including a primary (Larix or Pseudotsuga) and a secondary (Picea, Pinus, or Abies) host. For the S. punctatipes bioassay, an additional treatment in which the primary host was removed after 8 mo was included to assess the effect of primary host presence on longer-term ECM colonization. The field-based results confirmed that Suillus fungi were able to associate with Abies and Tsuga hosts, representing novel host genera for this genus. In the bioassays, colonization on the primary hosts was detected in both single- and two-species treatments, but no colonization was present when Picea and Abies hosts were grown alone. Removal of a primary host had no effect on percent ECM colonization, suggesting that primary hosts are not necessary for sustaining Suillus colonization once they are successfully established on secondary hosts. Collectively, our results indicate that host specificity is more flexible in this genus than previously acknowledged and help to explain the presence of Suillus in forests where recognized hosts are not present.


Assuntos
Abies , Micorrizas , Picea , Pinus , Especificidade de Hospedeiro , Micorrizas/genética
17.
Mol Ecol ; 30(18): 4433-4447, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34218489

RESUMO

Trees must cope with the attack of multiple pathogens, often simultaneously during their long lifespan. Ironically, the genetic and molecular mechanisms controlling this process are poorly understood. The objective of this study was to compare the genetic component of resistance in Norway spruce to Heterobasidion annosum s.s. and its sympatric congener Heterobasidion parviporum. Heterobasidion root- and stem-rot is a major disease of Norway spruce caused by members of the Heterobasidion annosum species complex. Resistance to both pathogens was measured using artificial inoculations in half-sib families of Norway spruce trees originating from central to northern Europe. The genetic component of resistance was analysed using 63,760 genome-wide exome-capture sequenced SNPs and multitrait genome-wide associations. No correlation was found for resistance to the two pathogens; however, associations were found between genomic variants and resistance traits with synergic or antagonist pleiotropic effects to both pathogens. Additionally, a latitudinal cline in resistance in the bark to H. annosum s.s. was found; trees from southern latitudes, with a later bud-set and thicker stem diameter, allowed longer lesions, but this was not the case for H. parviporum. In summary, this study detects genomic variants with pleiotropic effects which explain multiple disease resistance from a genic level and could be useful for selection of resistant trees to both pathogens. Furthermore, it highlights the need for additional research to understand the evolution of resistance traits to multiple pathogens in trees.


Assuntos
Basidiomycota , Picea , Basidiomycota/genética , Genômica , Homicídio , Noruega , Picea/genética , Doenças das Plantas/genética
18.
Molecules ; 26(12)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207740

RESUMO

In this study, formaldehyde-free bioresin adhesives were synthesised from lignin and tannin, which were obtained from softwood bark. The extraction was done via organosolv treatment and hot water extraction, respectively. A non-volatile, non-toxic aldehyde, glyoxal, was used as a substitute for formaldehyde in order to modify the chemical structure of both the lignin and tannin. The glyoxal modification reaction was confirmed by ATR-FTIR spectroscopy. Three different resin formulations were prepared using modified lignin along with the modified tannin. The thermal properties of the modified lignin, tannin, and the bioresins were assessed by DSC and TGA. When the bioresins were cured at a high temperature (200 °C) by compression moulding, they exhibited higher thermal stability as well as an enhanced degree of cross-linking compared to the low temperature-cured bioresins. The thermal properties of the resins were strongly affected by the compositions of the resins as well as the curing temperatures.


Assuntos
Lignina/química , Picea/química , Casca de Planta/química , Resinas Vegetais/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Taninos/química , Adesivos/química , Glioxal/química , Química Verde/instrumentação , Química Verde/métodos , Temperatura Alta , Madeira/química
19.
Ying Yong Sheng Tai Xue Bao ; 32(7): 2363-2370, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34313053

RESUMO

According to the technical specifications of CTFS (Center for Tropical Forest Science), 190 sampling points of 4-hm2 plot (GDS plot) in Guandi Mountains of Shanxi Province, China were investigated to examine the spatial distribution pattern of seedlings and 14 soil indicators, including pH value and nutrient indicators. We analyzed the spatial associations between tree regeneration and soil nutrients, explored the mechanism of tree regeneration pattern of secon-dary Picea forest. The results showed that more seedlings survived in the patches with low contents of available N, available K, available Cu, available Fe, available Mn, available Ni and available Zn. Besides available K, the negative correlation between the other six soil nutrient factors and the number of regeneration seedlings of the Ⅱ (2.5 cm

Assuntos
Picea , Árvores , China , Florestas , Nutrientes , Solo
20.
Chemosphere ; 279: 130631, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34134422

RESUMO

The Hg isotopic composition of 1-year-old Norway spruce (Picea abies) shoots collected from Saarland cornurbation Warndt, Germany, since 1985 by the German Environmental Specimen Bank, were measured for a better understanding of the temporal trends of Hg sources. The isotopic data showed that Hg was mainly taken up as gaseous element mercury (GEM) and underwent oxidation in the spruce needles; this led to a significant decrease in the δ202Hg compared with the atmospheric Hg isotopic composition observed for deciduous leaves and epiphytic lichens. Observation of the odd mass-independent isotopic fractionation (MIF) indicated that Δ199Hg and Δ201Hg were close to but slightly lower than the actual values recorded from the atmospheric measurement of the GEM isotopic composition in non-contaminated sites in U.S. and Europe, whereas observation of the even-MIF indicated almost no differences for Δ200Hg. This confirmed that GEM is a major source of Hg accumulation in spruce shoots. Interestingly, the Hg isotopic composition in the spruce shoots did not change very significantly during the study period of >30 years, even as the Hg concentration decreased significantly. Even-MIF (Δ200Hg) and mass-dependent fractionation (MDF) (δ202Hg) of the Hg isotopes exhibited slight decrease with time, whereas odd-MIF did not show any clear trend. These results suggest a close link between the long-term evolution of GEM isotopic composition in the air and the isotopic composition of bioaccumulated Hg altered by mass-dependent fraction in the spruce shoots.


Assuntos
Mercúrio , Picea , Monitoramento Ambiental , Europa (Continente) , Alemanha , Mercúrio/análise , Isótopos de Mercúrio/análise , Noruega
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