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1.
Int J Mol Sci ; 25(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38396759

RESUMO

Caragana, a xerophytic shrub genus widely distributed in northern China, exhibits distinctive geographical substitution patterns and ecological adaptation diversity. This study employed transcriptome sequencing technology to investigate 12 Caragana species, aiming to explore genic-SSR variations in the Caragana transcriptome and identify their role as a driving force for environmental adaptation within the genus. A total of 3666 polymorphic genic-SSRs were identified across different species. The impact of these variations on the expression of related genes was analyzed, revealing a significant linear correlation (p < 0.05) between the length variation of 264 polymorphic genic-SSRs and the expression of associated genes. Additionally, 2424 polymorphic genic-SSRs were located in differentially expressed genes among Caragana species. Through weighted gene co-expression network analysis, the expressions of these genes were correlated with 19 climatic factors and 16 plant functional traits in various habitats. This approach facilitated the identification of biological processes associated with habitat adaptations in the studied Caragana species. Fifty-five core genes related to functional traits and climatic factors were identified, including various transcription factors such as MYB, TCP, ARF, and structural proteins like HSP90, elongation factor TS, and HECT. The roles of these genes in the ecological adaptation diversity of Caragana were discussed. Our study identified specific genomic components and genes in Caragana plants responsive to heterogeneous habitats. The results contribute to advancements in the molecular understanding of their ecological adaptation, lay a foundation for the conservation and development of Caragana germplasm resources, and provide a scientific basis for plant adaptation to global climate change.


Assuntos
Caragana , Caragana/genética , Perfilação da Expressão Gênica/métodos , Transcriptoma , Genes de Plantas , Fenótipo , Repetições de Microssatélites
2.
Sci China Life Sci ; 67(2): 403-413, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37606847

RESUMO

Global climate change has led to the decline of species and functional diversity in ecosystems, changing community composition and ecosystem functions. However, we still know little about how species with different resource-use strategies (different types of resource usage and plant growth of plants as indicated by the spectrum of plant economic traits, including acquisitive resource-use strategy and conservative resource-use strategy) would change in response to climate change, and how the changes in the diversity of species with different resource-use strategies may influence community-level productivity. Here, using long-term (1982-2017) observatory data in a temperate grassland in Inner Mongolia, we investigated how climate change had affected the species richness (SR) and functional richness (FRic) for the whole community and for species with different resource-use strategies. Specifically, based on data for four traits representing leaf economics spectrum (leaf carbon concentration, leaf nitrogen concentration, leaf phosphorus concentration, and specific leaf area), we divided 81 plant species appearing in the grassland community into three plant functional types representing resource-acquisitive, medium, and resource-conservative species. We then analyzed the changes in community-level productivity in response to the decline of SR and FRic at the community level and for different resource-use strategies. We found that community-level SR and FRic decreased with drying climate, which was largely driven by the decline of diversity for resource-acquisitive species. However, community-level productivity remained stable because resource-conservative species dominating this grassland were barely affected by climate change. Our study revealed distinctive responses of species with different resource-use strategies to climate change and provided a new approach based on species functional traits for predicting the magnitude and direction of climate change effects on ecosystem functions.


Assuntos
Ecossistema , Pradaria , Mudança Climática , Plantas , China , Biodiversidade
3.
Heliyon ; 9(9): e20095, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809804

RESUMO

Background: We previously reported that obese mice had significantly high lipid content in embryos, and excessive lipids are detrimental to embryonic development. However, whether maternal obesity has an effect on embryonic vitrification injury and subsequent pregnancy outcomes is still controversial. This study was conducted to clarify the influence of maternal obesity on embryonic vitrification injury and subsequent pregnancy outcomes by in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI). Methods: We retrospectively collected medical record of IVF/ICSI patients from reproductive medicine centers in two tertiary hospitals. The patients were classified into a low-weight group (<18.5 kg/m2), normal-weight group (18.5-23.9 kg/m2), overweight group (24.0-27.9 kg/m2) and obese group (≥28.0 kg/m2) according to their body mass index (BMI). Multivariable logistic regression analysis was performed to compare pregnancy outcomes in fresh and frozen embryo transfer among different BMI groups to define the correlation between BMI and embryonic vitrification injury. Results: A total of 44 773 women among 20-40 years old were recruited in this study, of which 27 797 underwent their first fresh embryo transfer and 16 976 underwent their first frozen embryo transfer. For fresh embryo transfer, there was no significant difference in the clinical pregnancy rate, live birth rate, and miscarriage rate of 4 BMI groups. For frozen-thawed embryo transfer, there was a significant increase in the clinical pregnancy rate of the overweight group (AOR = 1.14, 95% CI: 1.05-1.25) and the obese group (AOR = 1.24, 95% CI: 1.03-1.50), while the miscarriage rate (AOR = 1.42, 95% CI: 1.05-1.92) also showed a significant increase in the obese group compared to the normal-weight group. Conclusion: This study provided a new understanding of the effect of maternal obesity on embryonic vitrification injury. Maternal obesity does not worsen the outcome of IVF/ICSI, particularly in the frozen-thawed group.

4.
Glob Chang Biol ; 29(24): 7072-7084, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37795748

RESUMO

Anthropogenic eutrophication is known to impair the stability of aboveground net primary productivity (ANPP), but its effects on the stability of belowground (BNPP) and total (TNPP) net primary productivity remain poorly understood. Based on a nitrogen and phosphorus addition experiment in a Tibetan alpine grassland, we show that nitrogen addition had little impact on the temporal stability of ANPP, BNPP, and TNPP, whereas phosphorus addition reduced the temporal stability of BNPP and TNPP, but not ANPP. Significant interactive effects of nitrogen and phosphorus addition were observed on the stability of ANPP because of the opposite phosphorus effects under ambient and enriched nitrogen conditions. We found that the stability of TNPP was primarily driven by that of BNPP rather than that of ANPP. The responses of BNPP stability cannot be predicted by those of ANPP stability, as the variations in responses of ANPP and BNPP to enriched nutrient, with ANPP increased while BNPP remained unaffected, resulted in asymmetric responses in their stability. The dynamics of grasses, the most abundant plant functional group, instead of community species diversity, largely contributed to the ANPP stability. Under the enriched nutrient condition, the synchronization of grasses reduced the grass stability, while the latter had a significant but weak negative impact on the BNPP stability. These findings challenge the prevalent view that species diversity regulates the responses of ecosystem stability to nutrient enrichment. Our findings also suggest that the ecological consequences of nutrient enrichment on ecosystem stability cannot be accurately predicted from the responses of aboveground components and highlight the need for a better understanding of the belowground ecosystem dynamics.


Assuntos
Ecossistema , Pradaria , Tibet , Nitrogênio , Fósforo , Poaceae
5.
Plant Physiol ; 192(1): 205-221, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36756926

RESUMO

Flowering time is one of the most important agronomic traits affecting the adaptation and yield of rice (Oryza sativa). Heading date 1 (Hd1) is a key factor in the photoperiodic control of flowering time. In this study, two basic helix-loop-helix (bHLH) transcription factors, Hd1 Binding Protein 1 (HBP1) and Partner of HBP1 (POH1) were identified as transcriptional regulators of Hd1. We generated knockout mutants of HBP1 and ectopically expressed transgenic lines of the two bHLH transcription factors and used these lines to investigate the roles of these two factors in regulating flowering time. HBP1 physically associated with POH1 forming homo- or heterodimers to perform their functions. Both HBP1 and POH1 bound directly to the cis-acting elements located in the promoter of Hd1 to activate its expression. CRISPR/Cas9-generated knockout mutations of HBP1, but not POH1 mutations, promoted earlier flowering time; conversely, HBP1 and POH1 overexpression delayed flowering time in rice under long-day and short-day conditions by activating the expression of Hd1 and suppressing the expression of Early heading date 1 (Ehd1), Heading date 3a (Hd3a), and Rice Flowering locus T 1 (RFT1), thus controlling flowering time in rice. Our findings revealed a mechanism for flowering time control through transcriptional regulation of Hd1 and laid theoretical and practical foundations for improving the growth period, adaptation, and yield of rice.


Assuntos
Flores , Oryza , Oryza/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fotoperíodo , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
6.
J Obstet Gynaecol Res ; 49(4): 1206-1213, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36738078

RESUMO

BACKGROUND: Both in vitro fertilization and embryo transfer (IVF-ET) and intracytoplasmic sperm injection and embryo transfer (ICSI-ET) have been recommended for unexplained primary infertility after recurrent artificial insemination with homologous semen failure (UAIHF), but few studies focused on the safety and efficiency of the IVF/ICSI-ET technique for these patients. In this study, we compared the IVF/ICSI-ET outcomes and perinatal and postnatal complications between UAIHF patients and tubal infertility (TI) patients. METHODS: We conducted a retrospective study of UAIHF and TI patients who underwent IVF/ICSI-ET at Guangxi Reproductive Medical Center, the First Affiliated Hospital of Guangxi Medical University from January 2012 to March 2021. After propensity score matching (PSM), we analyzed the IVF/ICSI-ET outcomes and rates of perinatal and postnatal complications. RESULTS: PSM analysis revealed that the baselines of age, infertility duration, and body mass index were comparable. The fertilization method was significantly different between the two groups. Through IVF/ICSI-ET, UAIHF patients had a similar clinical outcome compared to TI patients. Regarding perinatal and postnatal complications, the incidence of premature rupture of membranes (PROM) (7.54% vs. 3.17%, p = 0.030) was significantly higher in UAIHF patients. CONCLUSIONS: UAIHF patients could achieve satisfying pregnancy outcomes by IVF/ICSI-ET. ICSI-ET did not seem to improve the clinical outcomes of UAIHF patients compared to those of TI patients who underwent IVF-ET, which might be related to possible underlying diseases in these patients. In addition, the incidence of PROM was significantly higher in UAIHF patients, which might be related to the ICSI technique used and uncertain potential idiopathic diseases associated with unexplained infertility patients. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2200057572. Registered 15 March 2022.


Assuntos
Infertilidade , Injeções de Esperma Intracitoplásmicas , Feminino , Humanos , Masculino , Gravidez , China/epidemiologia , Transferência Embrionária , Fertilização in vitro/métodos , Inseminação Artificial , Taxa de Gravidez , Prognóstico , Estudos Retrospectivos , Sêmen , Injeções de Esperma Intracitoplásmicas/métodos
7.
Microb Ecol ; 85(3): 1013-1027, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35364696

RESUMO

Soil microbes assemble in highly complex and diverse microbial communities, and microbial diversity patterns and their drivers have been studied extensively. However, diversity correlations and co-occurrence patterns between bacterial, fungal, and archaeal domains and between microbial functional groups in arid regions remain poorly understood. Here we assessed the relationships between the diversity and abundance of bacteria, fungi, and archaea and explored how environmental factors influence these relationships. We sampled soil along a 1500-km-long aridity gradient in temperate grasslands of Inner Mongolia (China) and sequenced the 16S rRNA gene of bacteria and archaea and the ITS2 gene of fungi. The diversity correlations and co-occurrence patterns between bacterial, fungal, and archaeal domains and between different microbial functional groups were evaluated using α-diversity and co-occurrence networks based on microbial abundance. Our results indicate insignificant correlations among the diversity patterns of bacterial, fungal, and archaeal domains using α-diversity but mostly positive correlations among diversity patterns of microbial functional groups based on α-diversity and co-occurrence networks along the aridity gradient. These results suggest that studying microbial diversity patterns from the perspective of functional groups and co-occurrence networks can provide additional insights on patterns that cannot be accessed using only overall microbial α-diversity. Increase in aridity weakens the diversity correlations between bacteria and fungi and between bacterial and archaeal functional groups, but strengthens the positive diversity correlations between bacterial functional groups and between fungal functional groups and the negative diversity correlations between bacterial and fungal functional groups. These variations of the diversity correlations are associated with the different responses of microbes to environmental factors, especially aridity. Our findings demonstrate the complex responses of microbial community structure to environmental conditions (especially aridity) and suggest that understanding diversity correlations and co-occurrence patterns between soil microbial groups is essential for predicting changes in microbial communities under future climate change in arid regions.


Assuntos
Pradaria , Solo , Solo/química , Microbiologia do Solo , RNA Ribossômico 16S/genética , Fungos/genética , Bactérias/genética , Archaea/genética
8.
Elife ; 112022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36206306

RESUMO

Extending knowledge on ecosystem stability to larger spatial scales is urgently needed because present local-scale studies are generally ineffective in guiding management and conservation decisions of an entire region with diverse plant communities. We investigated stability of plant productivity across spatial scales and hierarchical levels of organization and analyzed impacts of dominant species, species diversity, and climatic factors using a multisite survey of Inner Mongolian grassland. We found that regional stability across distant local communities was related to stability and asynchrony of local communities. Using only dominant instead of all-species dynamics explained regional stability almost equally well. The diversity of all or only dominant species had comparatively weak effects on stability and synchrony, whereas a lower mean and higher variation of precipitation destabilized regional and local communities by reducing population stability and synchronizing species dynamics. We demonstrate that, for semi-arid temperate grassland with highly uneven species abundances, the stability of regional communities is increased by stability and asynchrony of local communities and these are more affected by climate rather than species diversity. Reduced amounts and increased variation of precipitation in the future may compromise the sustainable provision of ecosystem services to human well-being in this region.


Assuntos
Ecossistema , Pradaria , Animais , Biodiversidade , Clima , Gerbillinae , Humanos , Plantas
9.
Plants (Basel) ; 11(12)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35736727

RESUMO

Phosphatidylethanolamine-binding-protein (PEBP) domain-containing proteins play important roles in multiple developmental processes of plants; however, functions of few members in the PEBP gene family have been elucidated in rice and other crops. In this study, we found that twenty OsPEBPs genes identified in rice are not evenly distributed on the chromosomes. Four colinear pairs are identified, suggesting the duplication of OsPEBPs during evolution. The OsPEBPs are classified into six subgroups by phylogenetic analysis. The structure of all the OsPEBP genes and encoded proteins are similar. The 262 PEBP domain-containing proteins from crops are divided into six groups. The number of colinear pairs varies between rice and other crops. More than thirty cis-acting elements in the promoter region of OsPEBPs are discovered. Expression profiles of OsPEBP genes are differential. Most of the OsPEBPs expression can be regulated by NaCl, ABA, JA, and light, indicating that OsPEBPs may be involved in the control of the response to the environmental signals. These results lay sound foundation to further explore their functions in development of rice and crops.

10.
Microorganisms ; 9(9)2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34576824

RESUMO

Changes in species composition across communities, i.e., ß-diversity, is a central focus of ecology. Compared to macroorganisms, the ß-diversity of soil microbes and its drivers are less studied. Whether the determinants of soil microbial ß-diversity are consistent between soil depths and between abundant and rare microorganisms remains controversial. Here, using the 16S-rRNA of soil bacteria and archaea sampled at different soil depths (0-10 and 30-50 cm) from 32 sites along an aridity gradient of 1500 km in the temperate grasslands in northern China, we compared the effects of deterministic and stochastic processes on the taxonomic and phylogenetic ß-diversity of soil microbes. Using variation partitioning and null models, we found that the taxonomic ß-diversity of the overall bacterial communities was more strongly determined by deterministic processes in both soil layers (the explanatory power of environmental distance in topsoil: 25.4%; subsoil: 47.4%), while their phylogenetic counterpart was more strongly determined by stochastic processes (the explanatory power of spatial distance in topsoil: 42.1; subsoil 24.7%). However, in terms of abundance, both the taxonomic and phylogenetic ß-diversity of the abundant bacteria in both soil layers was more strongly determined by deterministic processes, while those of rare bacteria were more strongly determined by stochastic processes. In comparison with bacteria, both the taxonomic and phylogenetic ß-diversity of the overall abundant and rare archaea were strongly determined by deterministic processes. Among the variables representing deterministic processes, contemporary and historical climate and aboveground vegetation dominated the microbial ß-diversity of the overall and abundant microbes of both domains in topsoils, but soil geochemistry dominated in subsoils. This study presents a comprehensive understanding on the ß-diversity of soil microbial communities in the temperate grasslands in northern China. Our findings highlight the importance of soil depth, phylogenetic turnover, and species abundance in the assembly processes of soil microbial communities.

11.
Plant Cell Physiol ; 61(12): 2111-2125, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33067639

RESUMO

Tiller angle is a key factor determining rice plant architecture, planting density, light interception, photosynthetic efficiency, disease resistance and grain yield. However, the mechanisms underlying tiller angle control are far from clear. In this study, we identified a mutant, termed bta1-1, with an enlarged tiller angle throughout its life cycle. A detailed analysis reveals that BTA1 has multiple functions because tiller angle, shoot gravitropism and tolerance to drought stress are changed in bta1-1 plants. Moreover, BTA1 is a positive regulator of shoot gravitropism in rice. Shoot responses to gravistimulation are disrupted in bta1-1 under both light and dark conditions. Gene cloning reveals that bta1-1 is a novel mutant allele of LA1 renamed la1-SN. LA1 is able to rescue the tiller angle and shoot gravitropism defects observed in la1-SN. The nuclear localization signal of LA1 is disrupted by la1-SN, causing changes in its subcellular localization. LA1 is required to regulate the expression of auxin transporters and signaling factors that control shoot gravitropism and tiller angle. High-throughput mRNA sequencing is performed to elucidate the molecular and cellular functions of LA1. The results show that LA1 may be involved in the nucleosome and chromatin assembly, and protein-DNA interactions to control gene expression, shoot gravitropism and tiller angle. Our results provide new insight into the mechanisms whereby LA1 controls shoot gravitropism and tiller angle in rice.


Assuntos
Regulação da Expressão Gênica de Plantas/fisiologia , Gravitropismo , Ácidos Indolacéticos/metabolismo , Oryza/fisiologia , Proteínas de Plantas/fisiologia , Brotos de Planta/fisiologia , Transporte Biológico/fisiologia , Genes de Plantas/fisiologia , Oryza/metabolismo , Brotos de Planta/metabolismo , Transdução de Sinais/fisiologia
12.
Proc Biol Sci ; 287(1928): 20200675, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32486982

RESUMO

Biotic mechanisms associated with species diversity are expected to stabilize communities in theoretical and experimental studies but may be difficult to detect in natural communities exposed to large environmental variation. We investigated biotic stability mechanisms in a multi-site study across Inner Mongolian grassland characterized by large spatial variations in species richness and composition and temporal fluctuations in precipitation. We used a new additive-partitioning method to separate species synchrony and population dynamics within communities into different species-abundance groups. Community stability was independent of species richness but was regulated by species synchrony and population dynamics, especially of abundant species. Precipitation fluctuations synchronized population dynamics within communities, reducing their stability. Our results indicate generality of biotic stability mechanisms in natural ecosystems and suggest that for accurate predictions of community stability in changing environments uneven species composition should be considered by partitioning stabilizing mechanisms into different species-abundance groups.


Assuntos
Pradaria , Animais , Biodiversidade , China , Ecossistema , Gerbillinae , Dinâmica Populacional
13.
Sci Total Environ ; 718: 137252, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32325613

RESUMO

The relationships between biodiversity and ecosystem functioning (BEF) have been extensively studied over past decades. However, the environmental factors affecting their relationships, and how their relationships vary under the influence of environmental factors, remain controversial. Studying the BEF relationships in natural/wild environments is of great significance for devising strategies in biodiversity conservation and ecosystem functioning. Using the data from 75 sites on the Mongolian Plateau steppe, we analyzed the relationship between species richness and biomass with general linear models (GLMs) and linear mixed models (LMMs), and analyzed the variation in the species richness-biomass relationships under environmental conditions by the partial least square path modeling (PLSPM). The results showed that de Martonne aridity index affected both species richness and community biomass in parallel, and that hydrothermal coupling conditions were more important direct impact factors for aboveground biomass. However, the significant species richness-biomass relationships became weaker when the effects of environmental factors (i.e. climate and soil properties) were present. Climate humidity was the most important factor in mediating the relationship between species richness and community biomass. Our research suggested that species richness-biomass relationships are weak in the natural grasslands of the Mongolian Plateau, and that this may be due to the differences in the regional-scale environment and changes in species interactions. We recommend that a more comprehensive understanding of the relationship between diversity and biomass requires further research within broader environmental gradients.


Assuntos
Biodiversidade , Biomassa , Umidade , Solo
14.
mSystems ; 4(5)2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31575667

RESUMO

Biogeographic patterns and drivers of soil microbial diversity have been extensively studied in the past few decades. However, most research has focused on the topsoil, while the subsoil is assumed to have microbial diversity patterns similar to those of the topsoil. Here we compared patterns and drivers of microbial alpha and beta diversity in and between topsoils (0 to 10 cm) and subsoils (30 to 50 cm) of temperate grasslands in Inner Mongolia of China, covering an ∼1,500-km transect along an aridity gradient. Counter to the conventional assumption, we find contrasting biogeographic patterns of diversity and influencing factors for different bacterial and archaeal groups and between depths. While bacterial diversity remains constant or increases with increasing aridity in topsoil and decreases in subsoil, archaeal diversity decreases in topsoil and remains constant in subsoil. Microbial diversity in the topsoil is most strongly influenced by aboveground vegetation and contemporary climate but is most strongly influenced by the factor historical temperature anomaly since the Last Glacial Maximum (LGM) and by soil pH in the subsoil. Moreover, the biogeographic patterns of topsoil-subsoil community dissimilarities vary for different microbial groups and are overall most strongly influenced by soil fertility differences between depths for bacteria and by contemporary climate for archaea. These findings suggest that diversity patterns observed in the topsoil may not be readily applied to the subsoil horizons. For the subsoil in particular, historical climate plays a vital role in the spatial variation of bacterial diversity. Overall, our study provides novel information for understanding and predicting soil microbial diversity patterns at depth.IMPORTANCE Exploring the biogeographic patterns of soil microbial diversity is critical for understanding mechanisms underlying the response of soil processes to climate change. Using top- and subsoils from an ∼1,500-km temperate grassland transect, we find divergent patterns of microbial diversity and its determinants in the topsoil versus the subsoil. Furthermore, we find important and direct legacy effects of historical climate change on the microbial diversity of subsoil yet indirect effects on topsoil. Our findings challenge the conventional assumption of similar geographic patterns of soil microbial diversity along soil profiles and help to improve our understanding of how soil microbial communities may respond to future climate change in different regions with various climate histories.

15.
Ecology ; 100(3): e02624, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30644535

RESUMO

Positive biodiversity-ecosystem-functioning (BEF) relationships are commonly found in experimental and observational studies, but how they vary in different environmental contexts and under the influence of coexisting life forms is still controversial. Investigating these variations is important for making predictions regarding the dynamics of plant communities and carbon pools under global change. We conducted this study across 433 shrubland sites in northern China. We fitted structural equation models (SEMs) to analyze the variation in the species-richness-biomass relationships of shrubs and herbs along a wetness gradient and general liner models (GLMs) to analyze how shrub or herb biomass affected the species-richness-biomass relationship of the other life form. We found that the positive species-richness-biomass relationships for both shrubs and herbs became weaker or even negative with higher water availability, likely indicating stronger interspecific competition within life forms under more benign conditions. After accounting for variation in environmental contexts using residual regression, we found that the benign effect of greater facilitation by a larger shrub biomass reduced the positive species-richness-biomass relationships of herbs, causing them to become nonsignificant. Different levels of herb biomass, however, did not change the species-richness-biomass relationship of shrubs, possibly because greater herb biomass did not alter the stress level for shrubs. We conclude that biodiversity in the studied plant communities is particularly important for plant biomass production under arid conditions and that it might be possible to use shrubs as nurse plants to facilitate understory herb establishment in ecological restoration.


Assuntos
Ecossistema , Água , Biodiversidade , Biomassa , China
16.
Proc Natl Acad Sci U S A ; 115(16): 4033-4038, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29666316

RESUMO

Plant nitrogen (N) and phosphorus (P) content regulate productivity and carbon (C) sequestration in terrestrial ecosystems. Estimates of the allocation of N and P content in plant tissues and the relationship between nutrient content and photosynthetic capacity are critical to predicting future ecosystem C sequestration under global change. In this study, by investigating the nutrient concentrations of plant leaves, stems, and roots across China's terrestrial biomes, we document large-scale patterns of community-level concentrations of C, N, and P. We also examine the possible correlation between nutrient content and plant production as indicated by vegetation gross primary productivity (GPP). The nationally averaged community concentrations of C, N, and P were 436.8, 14.14, and 1.11 mg·g-1 for leaves; 448.3, 3.04 and 0.31 mg·g-1 for stems; and 418.2, 4.85, and 0.47 mg·g-1 for roots, respectively. The nationally averaged leaf N and P productivity was 249.5 g C GPP·g-1 N·y-1 and 3,157.9 g C GPP·g-1 P·y-1, respectively. The N and P concentrations in stems and roots were generally more sensitive to the abiotic environment than those in leaves. There were strong power-law relationships between N (or P) content in different tissues for all biomes, which were closely coupled with vegetation GPP. These findings not only provide key parameters to develop empirical models to scale the responses of plants to global change from a single tissue to the whole community but also offer large-scale evidence of biome-dependent regulation of C sequestration by nutrients.


Assuntos
Sequestro de Carbono , Carbono/análise , Ecossistema , Nitrogênio/análise , Fósforo/análise , Plantas/química , Atmosfera/química , Biomassa , China , Clima , Fazendas , Florestas , Pradaria , Humanos , Especificidade de Órgãos , Dispersão Vegetal , Folhas de Planta/química , Raízes de Plantas/química , Caules de Planta/química , Solo/química , Especificidade da Espécie
17.
Ecology ; 98(5): 1471, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28241374

RESUMO

Knowledge of plant functional traits and trait-environment interactions is important for characterizing species strategies and understanding ecological processes. However, comprehensive field data on both above- and belowground traits, together with their environmental variables are scarce. Biome-scale studies are particularly lacking. Here we present two large-scale data sets that include functional traits of leaves and fine roots and their corresponding soil and climatic variables in China's grasslands. Leaf, fine root, and soil samples were collected in three biogeographic regions: temperate grassland on the Inner Mongolia Plateau, alpine grassland on the Tibetan Plateau, and mountain grassland in the Xinjiang mountain areas. Field data were collected over two periods. The first data set collected between 2003 and 2004 includes 13 foliar traits (leaf mass per area, LMA; photosynthetic nitrogen use efficiency, PNUE; water use efficiency, WUE; stomatal conductance for water vapor, Gs; transpiration rate, TR; mass- and area-based photosynthetic capacity, Amass and Aarea; mass- and area-based carbon concentrations, Cmass and Carea; nitrogen concentrations, Nmass and Narea; and phosphorus concentrations, Pmass and Parea) for 170 species at 173 sites. The second data set collected between 2006 and 2007 includes six sets of analogous traits for both leaves and fine roots (C, N, and P concentrations; leaf thickness/root diameter; specific leaf area, SLA; specific root length, SRL; and tissue density) for 139 species at 82 sites, along with soil attributes (soil total and organic carbon, STC and SOC; total and available N, STN and SAN; total and available P, STP and SAP; pH, bulk density, and moisture). Moreover, associated information was also gathered, including geographical location (latitude, longitude, and altitude), climate (mean annual temperature, MAT; mean annual precipitation, MAP; growing season temperature, GST; growing season precipitation, GSP; potential evapotranspiration, PET; and actual evapotranspiration, AET) and site descriptions (vegetation and soil types). The data sets are unique because they integrate plant above- and belowground traits, climate, and soil factors over broad regional, elevational, and taxonomic ranges in understudied regions (e.g., the Tibetan Plateau). This is the only database on China's grassland species for unrestricted global access. These data sets will make a valuable contribution to future large-scale trait-based ecological studies.


Assuntos
Clima , Pradaria , Solo/química , China , Ecossistema , Folhas de Planta
18.
J Assist Reprod Genet ; 33(11): 1515-1523, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27544277

RESUMO

PURPOSE: The aims of the present study are to identify the mechanism(s) whereby obesity impairs fresh embryos and to clarify the effects of vitrification on lipid droplet content within embryos from maternally obese mice. METHODS: The diet-induced obesity mouse model was established, and the zygotes were captured and cultured to day 3. The eight-cell embryos were selected and divided into fresh and vitrified groups. The blastocysts derived from fresh embryos were used as a control. The expression profiles of endoplasmic reticulum (ER) stress genes (Atf4, Grp78, and Hsp70) and other genes (MnSOD, p53, Gadd45g, caspase-3, IGF-II, ZO-1, and E-cadherin) on day-3 fresh and post-warming eight-cell embryos from obese and control groups were determined. For day-5 fresh blastocysts and blastocysts previously vitrified on day 3, the expression profiles for all of the above genes were also determined. RESULTS: For the fresh group, obesity significantly upregulated Hsp70, p53, IGF-II, and ZO-1 expression in embryos on day 3 and notably upregulated Atf4, MnSOD, Gadd45g, caspase-3, ZO-1, and E-cadherin expression in blastocysts on day 5. For vitrified ones, obesity significantly upregulated Atf4, MnSOD, and Gadd45g expression in embryos on day 3 and notably upregulated Hsp70 expression and downregulated MnSOD in day 5 blastocysts previously vitrified on day 3. CONCLUSIONS: Obesity impairs fresh embryos and aggravates embryonic vitrification injury at a molecular level.


Assuntos
Blastocisto/patologia , Desenvolvimento Embrionário/genética , Obesidade/metabolismo , Vitrificação , Animais , Criopreservação , Transferência Embrionária , Chaperona BiP do Retículo Endoplasmático , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Humanos , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/patologia , Relações Materno-Fetais , Camundongos , Camundongos Obesos , Obesidade/genética , Obesidade/patologia
19.
Taiwan J Obstet Gynecol ; 55(1): 50-4, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26927248

RESUMO

OBJECTIVE: Poor ovarian response to ovarian hyperstimulation is one of the biggest challenges in assisted reproduction technology. Although many stimulation protocols have been established to improve clinical outcomes in poor ovarian responders (PORs), which protocol is the most effective remains controversial. Luteal-phase ovarian stimulation (LPOS) has been used in normal ovarian responders with satisfactory outcomes. However, the efficacy of LPOS in PORs is unclear. This study aimed to compare the efficacy of LPOS and GnRH antagonist (GnRH-ant) in PORs. MATERIALS AND METHODS: The clinical parameters in PORs who received LPOS (50 cycles in 39 patients) or GnRH-ant (158 cycles in 123 patients) were compared. RESULTS: Compared with those in the GnRH-ant group, the PORs in the LPOS group showed significantly fewer basal antral follicles (3.1 ± 2.2 vs. 4.1 ± 1.6, p < 0.001) and a higher in vitro fertilization rate. There were no significant differences in the numbers of retrieved oocytes and D3 transferable embryos between the two groups. However, the pregnancy rate in the LPOS group (46.4%) was significantly higher than that in the GnRH-ant group (25.8% overall; 22.9% from fresh embryos and 29.6% from frozen embryos). Moreover, 23 PORs in the LPOS group underwent oocyte retrieval twice in one cycle, and the numbers of retrieved oocytes and transferable embryos from the luteal phase were significantly higher than those from the follicular phase in the same menstrual cycle. CONCLUSIONS: Compared with the GnRH-ant protocol, the LPOS protocol may be a better regime for PORs that can increase the numbers of retrieved oocytes and transferable embryos as well as the pregnancy rate.


Assuntos
Fármacos para a Fertilidade Feminina/administração & dosagem , Antagonistas de Hormônios/administração & dosagem , Indução da Ovulação/métodos , Taxa de Gravidez , Injeções de Esperma Intracitoplásmicas , Adulto , Clomifeno/administração & dosagem , Transferência Embrionária , Estudos de Viabilidade , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Humanos , Letrozol , Fase Luteal , Menotropinas/administração & dosagem , Nitrilas/administração & dosagem , Recuperação de Oócitos , Folículo Ovariano , Gravidez , Estudos Retrospectivos , Triazóis/administração & dosagem
20.
Sci Rep ; 4: 5448, 2014 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-24965183

RESUMO

Allocation of limiting resources, such as nutrients, is an important adaptation strategy for plants. Plants may allocate different nutrients within a specific organ or the same nutrient among different organs. In this study, we investigated the allocation strategies of nitrogen (N) and phosphorus (P) in leaves, stems and roots of 126 shrub species from 172 shrubland communities in Northern China using scaling analyses. Results showed that N and P have different scaling relationships among plant organs. The scaling relationships of N concentration across different plant organs tended to be allometric between leaves and non-leaf organs, and isometric between non-leaf organs. Whilst the scaling relationships of P concentration tended to be allometric between roots and non-root organs, and isometric between non-root organs. In arid environments, plant tend to have higher nutrient concentration in leaves at given root or stem nutrient concentration. Evolutionary history affected the scaling relationships of N concentration slightly, but not affected those of P concentration. Despite fairly consistent nutrients allocation strategies existed in independently evolving lineages, evolutionary history and environments still led to variations on these strategies.


Assuntos
Ecossistema , Nitrogênio/metabolismo , Organogênese Vegetal/fisiologia , Fósforo/metabolismo , Estruturas Vegetais/metabolismo , China , Distribuição Tecidual
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