Hasil untuk "Plant ecology"

N. Salzman, Kuiechun Hung, Dipica Haribhai et al.

Antimicrobial peptides are important effectors of innate immunity throughout the plant and animal kingdoms. In the mammalian small intestine, Paneth cell α-defensins are antimicrobial peptides that contribute to host defense against enteric pathogens. To determine if α-defensins also govern intestinal microbial ecology, we analyzed the intestinal microbiota of mice expressing a human α-defensin gene (DEFA5) and in mice lacking an enzyme required for the processing of mouse α-defensins. In these complementary models, we detected significant α-defensin-dependent changes in microbiota composition, but not in total bacterial numbers. Furthermore, DEFA5-expressing mice had striking losses of segmented filamentous bacteria and fewer interleukin 17 (IL-17)-producing lamina propria T cells. Our data ascribe a new homeostatic role to α-defensins in regulating the makeup of the commensal microbiota.

C. Ettema, D. Wardle

J. Etherington, H. Ellenberg, G. K. Strutt

F. Stuart, Chapín Iii, E. Schulze et al.

P. Feeny

R. Schmid

L. Sack, C. Scoffoni

H. Reynolds, A. Packer, J. Bever et al.

Pasquale A. Marziliano, Maria F. Cataldo, Elisabetta Emo et al.

Mixed-species forests are increasingly promoted to improve forest functioning, yet their growth responses depend strongly on site conditions, stand structure, and management legacies, particularly in Mediterranean mountain environments. This study investigates how species mixture, stand structure, competition, and site conditions jointly influence tree growth and productivity in silver fir–beech forests of southern Italy. We combined stand-level indicators (current annual increment, recruitment period, structural diversity indices) with tree-level growth analyses based on basal area increment and linear mixed-effects models, comparing pure and mixed stands across three montane sites characterized by contrasting environmental conditions and management histories. Mixed stands showed higher productivity than monospecific stands, with increased current annual increment, shorter recruitment periods, and greater structural complexity. Linear mixed-effects modelling identified tree size, height, competition intensity, species identity, and stand mixture as key drivers of growth. Both species benefited from mixture, although silver fir showed a stronger positive response, with 12–15% higher Basal Area Increment (BAI) in mixed stands compared to pure stands, while beech gains were more moderate (5–8%). Structural diversity, quantified by Shannon and Gini indices, was markedly higher in mixed stands, indicating enhanced size differentiation and resource-use complementarity. Overall, the results demonstrate that productivity gains in silver fir–beech forests arise from the interaction between species mixture, stand structure, competition, and site-specific conditions. Species mixture enhances individual-tree growth primarily by modulating competitive interactions, with the magnitude of benefits varying across sites according to structural and management-related constraints. These findings provide quantitative support for site-adapted management strategies that promote mixed and structural diverse forests in Mediterranean mountain regions.

PEI Xiangli, XU Zhenghe, LIU Miao et al.

【Background and Objective】Soil salinization is a major constraint to sustainable agricultural production, and amending such soils with salt-tolerant microorganisms has been found to be effective in improving soil quality and enhancing crop tolerance to water and salinity stress. This paper analyzes international research in this area.【Method】Bibliometric analysis was conducted using VOSviewer and CiteSpace to systematically examine publications from 2004 to 2024 on saline-alkali soil microbiology retrieved from the China National Knowledge Infrastructure (CNKI, 652 articles) and the Web of Science Core Collection (WOS, 982 articles).【Result】Annual publications in saline–alkali soil microbiology showed a substantial increase during this period, with publications in English journals consistently and markedly overshadowing those in Chinese journals. China led the world, publishing 1 103 papers and collaborating with 26 countries, including Canada and the United Kingdom. Keyword clustering analysis showed that research hotspots in this field were: ①microbial community structure and its environmental drivers; ②mechanisms underlying plant-microbe interactions and their ecological functions; and ③ screening of salt-tolerant and growth-promoting microorganisms, as well as the mechanisms underlying biological remediation of saline-alkali soils. From 2004 to 2024, research on microbiology in saline-alkali soil can be divided into three stages: an early stage (2004—2015) emphasizing species identification and soil improvement; a middle stage (2016—2020) focusing on microbial community ecology and functional characterization; and the most recent stage (2021—2024) characterized by increased attention to the regulation of the microbe-soil-plant system.【Conclusion】Future research in saline-alkali soil microbiology will depend on international collaboration and interdisciplinary cooperation. Advances in multi-omics approaches, big data and artificial intelligence will enable systematic elucidation of microbial community assembly and functional regulation mechanisms, which will promote precision microbial management, functional strain development, and microbiome restoration. These advances will provide environmentally friendly solutions for remediating saline-alkali soils and sustaining agricultural production to meet the growing demand for food.

G. Arimura, K. Matsui, J. Takabayashi

Safa Rguez, Taycir Grati-Affes, Walid Yeddes et al.

Rguez, S., Grati-Affes, T., Yeddes, W., Hammami, M., and Hamrouni-Sellami, I. 2024. Chemometric analysis of essential oils from Tunisian plants: Unravelling the antifungal potential against Botrytis cinerea. Tunisian Journal of Plant Protection 19 (1): 13-26.

Zhihuan Tao, Xuexia Miao, Zhenying Shi

Erika S. Santos, Maria Manuela Abreu, Sabina Rossini-Oliva

Small abandoned mining areas of Fe and Mn oxides located in the Portuguese sector of the Iberian Pyrite Belt (SW of Europe) have been converted into agrosilvopastoral systems with very few environmental management measures after their closure. Although at the landscape scale, no visible differences were observed between the former mining intervention areas and adjacent areas, it is essential to assess the state and environmental risk of the soil–plant system, especially in the herbaceous pastures grazed by domestic animals. This was carried out in the Ferragudo mining area, where an agrosilvopastoral system, composed of holm oak and dryland pasture, had been established after the closure of the mine at ≈45 years. The soils presented neutral pH and variable fertility degree. The pseudo-total soil concentrations of Cu, Mo, and Zn exceeded the Portuguese limit values established for agriculture use (>180 mg Cu/kg; >8.2 mg Mo/kg; 349 mg Zn/kg), but their soil available fractions were small (<8.4% of the pseudo-total concentrations). Trees and herbaceous plants showed good development, and the concentrations of the elements (except Mn) were considered normal or sufficient. For Mn, most of the plant samples exceeded phytotoxic Mn values, but no visual signs of phytotoxicity were observed. Only the concentrations of Fe and K in the shoots of some herbaceous samples exceeded the maximum tolerable levels for cattle and sheep, so the risk to animals can be considered small since other sources are present in animal feed. In general, this agrosilvopastoral system did not pose a significant environmental risk.

D. Neher

Mohamed Abdalla, Iris Feigenwinter, Mark Richards et al.

This study used the ECOSSE model (v. 5.0.1) to simulate soil respiration (Rs) fluxes estimated from ecosystem respiration (R_eco) for eight European permanent grassland (PG) sites with varying grass species, soils, and management. The main aim was to evaluate the strengths and weaknesses of the model in estimating Rs from grasslands, and to gain a better understanding of the terrestrial carbon cycle and how Rs is affected by natural and anthropogenic drivers. Results revealed that the current version of the ECOSSE model might not be reliable for estimating daily Rs fluxes, particularly in dry sites. The daily estimated and simulated Rs ranged from 0.95 to 3.1 g CO₂-C m⁻², and from 0.72 to 1.58 g CO₂-C m⁻², respectively. However, ECOSSE could still be a valuable tool for predicting cumulative Rs from PG. The overall annual relative deviation (RD) value between the cumulative estimated and simulated annual Rs was 11.9%. Additionally, the model demonstrated accurate simulation of Rs in response to grass cutting and slurry application practices. The sensitivity analyses and attribution tests revealed that increased soil organic carbon (SOC), soil pH, temperature, reduced precipitation, and lower water table (WT) depth could lead to increased Rs from soils. The variability of Rs fluxes across sites and years was attributed to climate, weather, soil properties, and management practices. The study suggests the need for additional development and application of the ECOSSE model, specifically in dry and low input sites, to evaluate the impacts of various land management interventions on carbon sequestration and emissions in PG.

سیده الهام فرهنگ جو, سارا سعادتمند, رمضانعلی خاوری نژاد et al.

سابقه و هدف: برنج یکی از گیاهان زراعی مهم است که به ‌ویژه در مراحل اولیه رشد، به تنش شوری حساس است. امروزه کاربرد مواد تنظیم‌کننده رشد گیاهی مانند اسیدسالیسیلیک باعث ایجاد مقاومت گیاهان نسبت به تنش‌های محیطی از جمله شوری شده است. هدف از این تحقیق مطالعه اثر کاربرد اسیدسالیسیلیک بر برخی از خصوصیات مورفولوژیکی و بیوشیمیایی گیاه برنج تحت تنش شوری بود. مواد و روش‌ها: بدین منظور آرمایشی گلدانی به‌صورت فاکتوریل بر پایه طرح کاملاً تصادفی با پنج سطح شوری (0، 25، 50، 75، 100 میلی‌مولار کلرید سدیم) و سه سطح اسیدسالیسیلیک (0، 5/0 ،1 میلی‌مولار) روی برنج رقم ندا در سه تکرار انجام شد. صفات اتدازه‌گیری شامل درصد جوانه‌زنی، طول اندام هوایی و ریشه، میزان پروتئین کل، مالون‌دی‌آلدئید، پرولین و فعالیت برخی آنزیم‌های آنتی‌اکسیدانی بودند.یافته‌ها: نتایج حاصل از این تحقیق نشان داد که شوری باعث کاهش معنی‌دار بر میزان درصد جوانه‌زنی، طول ساقه و ریشه و کاهش فعالیت پروتئین شد. بیشترین درصد جوانه‌زنی در تیمار شاهد (بدون شوری) و شوری در سطح 25 میل مولار مشاهده شد و با افزایش سطح شوری تا غلظت 100 میلی مولار میزان جوانه زنی کاهش یافت. بیشترین میزان طول ساقه چه نیز در غلظت 25 میلی مولار شوری همراه با اسید سالیسیلیک در غلظت 5/0 میل مولار مشاهده شد. بیشترین و کمترین طول ریشه نیز به ترتیب در تیمار 75 میلی مولار شوری همراه با 1 میلی‌مولار سالیسیلیک اسید و تیمار 100 میلی‌مولار شوری بدون سالیسیلیک اسید بدست آمد. اندازه گیری میزان پروتئین در تیمار‌های مختلف مشحص شد که افزایش سطح شوری موجب کاهش میزان پروتیئن برگ بخصوص در تیمار 100 میلی‌مولار شوری گردید. در تمامی غلظت های شوری، سالیسیلیک اسید میزان پروتئین برگ را افزایش داد و با افزایش غلظت سالیسیلیک اسید از 0 به 1 میلی‌مولار موجب روند افزایشی میزان پروتیئن برگ گردید. بیشترین میزان پروتئین برگ در تیمار بدون شوری و غلظت 1 میلی‌مولار سالیسیلیک اسید اندازه گیری شد. شوری موجب افزایش فعالیت مالون دی آلدئید در سطح شوری 100 میلی ‌مولار نسبت به تیمارهای دیگر شد اما کاربرد سالیسیلیک اسید در غلظت های 5/0 و 1 میلی مولار موجب کاهش تولید آن شد. از طرف دیگر افزایش مقدار صفات بیوشیمیایی از جمله پرولین، آنزیم آنتی‌اکسیدانی (سوپراکسیددیسموتاز) نشان‌دهنده نقش مصرف یک میلی‌مولار اسیدسالیسیلیک بر افزایش تحمل این گیاه در برابر تنش شوری است. در حالی که تنش شوری، میزان فعالیت مالون‌دی‌آلدئید، فعالیت آنزیم آنتی‌اکسیدان (کاتالاز) افزایش یافت که کاربرد گیاه با اسیدسالیسیلیک با کاهش فعالیت این صفات، تنش اکسیداتیو را کاهش می‌دهد که باعث افزایش مقاومت گیاه تحت تنش می‌شود. نتیجه‌گیری: تیمار اسیدسالیسیلیک ویژگی های بررسی شده را بهبود می‌دهد و با فزایش صفات مورفولوژیکی (درصد جوانه‌زنی، پارامترهای رشد) و صفات بیوشیمیایی(پرولین، فعالیت پروتئین، آنزیم سوپراکسید دیسموتاز)، هم چنین با کاهش میزان فعالیت مالون‌دی‌آلدئید، آنزیم آنتی‌اکسیدان (کاتالاز) تنش اکسیداتیو را کاهش می‌دهد که باعث افزایش مقاومت گیاه تحت تنش شوری می‌شود. با توجه به اینکه بیشتر مناطق ایران از شوری رنج می برند پیشنهاد می گردد که با استفاده از هورمون گیاهی اسید سالیسیلیک طی تنش شوری در دراز مدت توجه بیشتری گردد، در تخفیف اثرات مخرب ناشی از تنش شوری مؤثر باشد.

E. Wolkovich, E. Cleland

J. Klimešová, J. Martínková, J. Pausas et al.

Abstract Plant modularity traits relevant to functions of on-spot persistence, space occupancy, resprouting after disturbance, as well as resource storage, sharing, and foraging have been underrepresented in functional ecology so far. This knowledge gap exists for multiple reasons. First, these functions and related traits have been considered less important than others (e.g., resource economics, organ-based traits). Second, collecting data for modularity traits can be difficult. Third, as a consequence of the previous points, there is a lack of standardized collection protocols. We now feel the time is ripe to provide a solid conceptual and terminological framework together with comparable protocols for plant modularity traits that can be applicable across species, regions and biomes. We identify a suite of 14 key traits, which are assembled into five groups. We discuss the functional relevance of each trait, supplying effective guidelines to assist in the use and selection of the most suitable traits in relation to specific research tasks. Finally, we are convinced that the systematic study and widespread assessment of plant modularity traits could bridge this knowledge gap. As a result, previously overlooked key functions could be incorporated into the functional ecology research-agenda, thus providing a more comprehensive understanding of plant and ecosystem functioning.

Kuldeep Joshi, Sandeep Sehgal, Meenakshi Gupta et al.

The present study was carried out in the year 2021 to estimate the biomass and Carbon stock of Pinus roxburghii. Ten quadrates of size 20×20 m2 were laid out randomly. Diameter at breast height (dbh) and tree height was measured as the primary data. The regression equation √V=0.05131+3.98598D–1.0245√D was used for determining the mean stem volume. The mean tree density, mean tree diameter, mean tree height and mean stem volume at the study site were 150 trees ha-1, 51.21 cm, 19.79 m and 157.17 m3 ha-1, respectively. Similarly, above ground biomass density (AGBD), below ground biomass density (BGBD), total biomass density (TBD) and total carbon density (TCD) at the study site was 93.99 Mg ha-1, 26.32 Mg ha-1, 120.30 Mg ha-1 and 56.54 Mg ha-1, respectively. Average eCO2 was 207.51 Mg ha-1. Average soil bulk density was 1.39 gm cm-3, soil ph 6.47, EC 0.13, SOC 6.31 gm kg-1, NPK 201.44 Mg ha-1, 26.50 Mg ha-1 and 56.66 Mg ha-1,respectively. The soils in the site were almost clay with average percent of sand, silt and clay as 32.44, 30.99 and 36.57, respectively.