scholarly journals Role of endophytic fungi in grass litter decomposition

2007 ◽  
Vol 13 ◽  
pp. 103-105
Author(s):  
T. Osono
Keyword(s):  
Litter Decomposition ◽  
Litter Quality ◽  
Fungal Endophytes ◽  
Published Data ◽  
Minor Effect ◽  
Slow Increase ◽  
Negative Effect ◽  
Litter Nitrogen ◽  
Low Nitrogen

Fungal endophytes of grasses affect ecosystem processes through mutualistic interactions with host plants, but how grass endophytes affect litter decomposition remains unclear. In this study, previously published data on litter quality and decomposition of grasses are summarised and effects of fungal endophytes of grasses on litter quality and decomposition are reviewed to discuss possible roles of endophytes in decomposition. Aboveground litters of grasses have relatively low nitrogen (N) and lignin contents and show slow increase of N and lignin contents during decomposition. Endophyte-infected litter have slightly lower N contents than non-infected litter, but the differences so far reported were not statistically significant. A negative effect of grass endophytes on litter decomposition rates was demonstrated, but the effect of endophyte infection on decomposition was not as strong as the effects of other biological and environmental factors. This suggests that grass endophytes have a relatively minor effect of on litter quality and decomposition, but more studies are necessary to verify this tentative conclusion. Keywords: decomposition, lignin, litter, nitrogen

scholarly journals Role of foliar fungal endophytes in litter decomposition among species and population origins

2016 ◽  
Vol 21 ◽  
pp. 50-56 ◽  
Author(s):  
P.E. Gundel ◽  
M. Helander ◽  
L.A. Garibaldi ◽  
B.R. Vázquez-de-Aldana ◽  
I. Zabalgogeazcoa ◽  
...  
Keyword(s):  
Litter Decomposition ◽  
Fungal Endophytes

Litter decomposition in Mediterranean ecosystems: Modelling the controlling role of climatic conditions and litter quality

2011 ◽  
Vol 49 ◽  
pp. 148-157 ◽  
Author(s):  
Guido Incerti ◽  
Giuliano Bonanomi ◽  
Francesco Giannino ◽  
Flora Angela Rutigliano ◽  
Daniela Piermatteo ◽  
...  
Keyword(s):  
Litter Decomposition ◽  
Litter Quality ◽  
Mediterranean Ecosystems ◽  
Climatic Conditions

Effects of base-cation fertilization on litter decomposition in a sugar maple forest in southern Quebec

1994 ◽  
Vol 24 (3) ◽  
pp. 447-452 ◽  
Author(s):  
T.K. Lukumbuzya ◽  
J.W. Fyles ◽  
B. Côté
Keyword(s):  
Mass Loss ◽  
Litter Decomposition ◽  
Sugar Maple ◽  
Litter Quality ◽  
Base Cation ◽  
Decomposition Processes ◽  
Negative Effect ◽  
Mesh Bags ◽  
Poor Site ◽  
Decomposer Community

Application of base-cation fertilizers has been shown to increase tree growth and vigour in declining sugar maple (Acersaccharum Marsh.) stands in southern Quebec but little is known about the effects of such fertilizers on litter quality or decomposition. Sugar maple foliage litters from fertilized and unfertilized plots on a base-poor site and from a naturally base-rich site were incubated in litterbags of 1- and 3-mm mesh sizes on fertilized and unfertilized plots at the base-poor site. Mass loss of unfertilized litter was slower in fertilized than in unfertilized plots, suggesting a negative effect of fertilization on the decomposer community. Faster mass loss of fertilized than unfertilized litter incubated in the same plot indicated that changes in litter quality brought about by fertilization enhanced decomposition. Mass loss of fertilized litter on fertilized plots did not differ from that of unfertilized litter on control plots, indicating that although decomposition processes are affected by fertilization the overall effect on decomposition is negligible. Mass loss was significantly, but only slightly, higher in large mesh than in small mesh bags indicating that larger soil fauna play a limited role in litter decomposition in this forest.

scholarly journals Impairment of the cellulose degradation machinery enhances fungal virulence but limits reproductive fitness

2021 ◽  
Author(s):  
Francisco M. Gamez-Arjona ◽  
Stefania Vitale ◽  
Aline Voxeur ◽  
Susanne Dora ◽  
Sascha Mueller ◽  
...  
Keyword(s):  
Plant Cell Wall ◽  
Cellulose Degradation ◽  
Fungal Endophytes ◽  
Cellulase Activity ◽  
Fungal Virulence ◽  
Negative Effect ◽  
Microbe Interactions ◽  
Evolutionary Success ◽  
Host Microbe Interactions

Fungal endophytes grow in the apoplastic space, in constant contact with the plant cell wall (CW) that hinders microbe progression, while representing a source of nutrients. Although numerous fungal CW modifying proteins have been identified, their role during host colonization remains underexplored. Here we show that the root-infecting plant pathogen Fusarium oxysporum (Fo) does not require its complete arsenal of cellulases to infect the host plant. Quite the opposite, Fo mutants impaired in cellulose degradation become hypervirulent by enhancing the secretion of virulence factors. On the other hand, the reduction on cellulase activity had a severe negative effect on saprophytic growth and microconidia production during the final stages of the Fo infection cycle. These findings enhance our understanding on the function of plant CW degradation on the outcome of host-microbe interactions and reveal an unexpected role of cellulose degradation in a pathogen's evolutionary success.

scholarly journals The importance of litter quality for the role of arbuscular mycorrhizal fungi in plant litter decomposition (short communication)

2016 ◽  
Author(s):  
E.F. Leifheit ◽  
M.C. Rillig
Keyword(s):  
Arbuscular Mycorrhizal Fungi ◽  
Litter Decomposition ◽  
Mycorrhizal Fungi ◽  
Litter Quality ◽  
Short Communication ◽  
C:N Ratio ◽  
Arbuscular Mycorrhizal ◽  
Plant Litter ◽  
Plant Litter Decomposition

AbstractArbuscular mycorrhizal fungi (AMF) have been shown to positively and negatively affect plant litter decomposition. The use of litter types with different quality and different observation periods might be responsible for these contradictory results. Therefore, we performed a 10-week laboratory experiment with 7 litter types differing in their C:N ratio, and tested for effects of litter quality and the presence of AMF on litter decomposition. We found that decomposition of plant litter with higher C:N ratios was only beginning and was stimulated by AMF, whereas decomposition of plant litter with lower C:N ratios had already progressed and was decreased by AMF. With this study we show that not only litter quality is important for effects of AMF on litter decomposition, but also the stage of litter decomposition.

scholarly journals Peer Support as a Mediator between Bullying Victimization and Depression

2018 ◽  
Vol 10 (1) ◽  
pp. 59 ◽  
Author(s):  
Chenguang Du ◽  
Kara DeGuisto ◽  
Jordan Albright ◽  
Sara Alrehaili
Keyword(s):  
School Violence ◽  
Peer Support ◽  
Intervention Program ◽  
The United States ◽  
Depression Symptoms ◽  
Published Data ◽  
School Aged Children ◽  
Negative Effect ◽  
The Relationship

Bullying has been one of the most common forms of school violence in the world. Being the victim of bullying has been shown by many studies to suffer from serious mental and physical issues. In the current study, the relationship among the victimization, peer support, and depression symptoms was assessed, using the published data from the 2009–2010 Health Behavior in School-Aged Children Survey (N = 12,642) collected from 314 publics, Catholic, and other private schools in the United States and enrolled in students from grades 5, 6, 7, 8, 9, and 10 or their equivalent in the 50 states and the District of Columbia. The results indicated: (1) The bullied victim is positively associated with the depression symptoms, with higher victimization reporting to have higher depression symptoms. (2) The bullied victim is negatively associated with peer support, with higher victimization reporting to have lower peer support. (3) The peer support was negatively related to depression symptoms. (4) The peer support partially mediates the relationship between the victimization and depression symptoms among bullied students. This empirical study underscores the important role of peer support in mitigating the negative effect of bullying on the victim’s depression symptoms. The current results also have meaningful implication to the bullying intervention program.   

Social Motives Predict Loneliness During a Developmental Transition

2017 ◽  
Vol 76 (4) ◽  
pp. 145-153 ◽  
Author(s):  
Jana Nikitin ◽  
Alexandra M. Freund
Keyword(s):  
Social Relationships ◽  
Well Being ◽  
Social Avoidance ◽  
Social Approach ◽  
Social Motives ◽  
Developmental Transitions ◽  
Avoidance Motivation ◽  
Negative Effect ◽  
Low Levels

Abstract. Establishing new social relationships is important for mastering developmental transitions in young adulthood. In a 2-year longitudinal study with four measurement occasions (T1: n = 245, T2: n = 96, T3: n = 103, T4: n = 85), we investigated the role of social motives in college students’ mastery of the transition of moving out of the parental home, using loneliness as an indicator of poor adjustment to the transition. Students with strong social approach motivation reported stable and low levels of loneliness. In contrast, students with strong social avoidance motivation reported high levels of loneliness. However, this effect dissipated relatively quickly as most of the young adults adapted to the transition over a period of several weeks. The present study also provides evidence for an interaction between social approach and social avoidance motives: Social approach motives buffered the negative effect on social well-being of social avoidance motives. These results illustrate the importance of social approach and social avoidance motives and their interplay during developmental transitions.

THE NOTHING THAT REALLY IS!

2016 ◽  
Vol 12 (1) ◽  
pp. 4172-4177
Author(s):  
Abdul Malek
Keyword(s):  
Quantum Dynamics ◽  
Theoretical Physics ◽  
Historical Evolution ◽  
Proper Understanding ◽  
Physical Universe ◽  
Wave Particle Duality ◽  
Negative Effect ◽  
Materialist Interpretation

The denial of the existence of contradiction is at the root of all idealism in epistemology and the cause for alienations.  This alienation has become a hindrance for the understanding of the nature and the historical evolution mathematics itself and its role as an instrument in the enquiry of the physical universe (1). A dialectical materialist approach incorporating  the role of the contradiction of the unity of the opposites, chance and necessity etc., can provide a proper understanding of the historical evolution of mathematics and  may ameliorate  the negative effect of the alienation in modern theoretical physics and cosmology. The dialectical view also offers a more plausible materialist interpretation of the bewildering wave-particle duality in quantum dynamics (2).

Peran Badan Pengendalian Dampak Lingkungan dalam Pengendalian Dampak Pencemaran Kegiatan Industri di Kota Batam tahun 2011-2014

2015 ◽  
Vol 14 (1) ◽  
pp. 20
Author(s):  
Wan Asrida ◽  
Dian Arival Aryadana
Keyword(s):  
Environmental Impact ◽  
Environmental Pollution ◽  
Pollution Control ◽  
Control Agency ◽  
Accurate Method ◽  
Industrial Activity ◽  
Research Issues ◽  
Negative Effect ◽  
Research Show

This research is intended to find out the role of the regional environmental impact Control Agency of Batam City against the environmental problems that occur in industrial areas namely, Batam city, concerning sustainable development based upon the environment, the activities of the industry now aims to build an economic sector but has a negative effect that is the pollution of the environment. In this case in Batam city frequent occurrence of environmental pollution caused by industrial activity namely with disposal of waste which are not in place. This research is focused on environmental impact Control Agency area of Batam city authorities in the control of the environment . With the outline of the research issues namely how environmental impact Control Agency the role of the Regions in the control of pollution of the environment against industrial activity in Batam city in 2011-2014 and the factors restricting the role of the regional environmental impact Control Agency in controlling environmental pollution in Batam city in 2011-2014.Type of this research is a descriptive i.e. researchers provide a description and overview of the phenomenon or social symptoms examined by independent variables described in a systematic and accurate. Method of data collection is done by means of interviews and the documentation.The results of this research show that the role of environmental impact Control Agency area of Batam city in pollution control against industrial activity carried out according to its function but have not run well in accordance with the goals and targets that have been set. This is not in accordance with the duties and functions of the regional environmental impact Control Agency of Batam city, resulting in less the maximum role of Bapedalda itself in controlling pollution that occurred in Batam city. So it should be should be able to stake Bapedalda holder which is professional in the discharge of pollution control and must be capable of tackling the obstacles faced.

Geometric Factor in Skeletal Reactions of 2-Methylpentane on Stepped Surfaces of Platinum Catalyst

1992 ◽  
Vol 57 (10) ◽  
pp. 2012-2020
Author(s):  
Vladimír Hejtmánek
Keyword(s):  
Active Sites ◽  
Platinum Catalyst ◽  
Point Of View ◽  
Geometric Factor ◽  
Published Data ◽  
Stepped Surfaces ◽  
Geometric Conditions ◽  
Surface Intermediates ◽  
Isomerization Mechanism

The role of geometric factor in the course of skeletal reactions (isomerization, hydrogenolysis) of 2-methylpentane on stepped (119), (557) and reconstructed R(557) surfaces of single crystals of platinum was evaluated with computer designed models. These calculations were compared with reported experimental data. It was found by analysis of geometric conditions that there are accessible active ensembles on double step of the reconstructed R(557) surface. In addition, these active sites are unsaturated in their coordination sphere and thus catalytically effective. This finding is consistent with published data, confirming higher catalytic activity of this surface. The various pathways of Bond Shift isomerization mechanism of 2-methylpentane from the point of view of steric demands of surface intermediates on differently located ensembles are discussed, too.

Sign in / Sign up

Export Citation Format

Share Document