scholarly journals Phosphorus and Nitrogen Modulate Plant Performance in Shrubby Legumes from the Iberian Peninsula

Plants ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 334 ◽  
Author(s):  
María Pérez-Fernández ◽  
Ángel Míguez-Montero ◽  
Alexandre Valentine
Keyword(s):  
Plant Biomass ◽  
Plant Performance ◽  
Physiological Basis ◽  
Retama Sphaerocarpa ◽  
Resistant Species ◽  
In The Wild ◽  
Use Efficiency ◽  
Effects Of Drought ◽  
Inoculation Treatment ◽  
The Impact

We investigated the impact of phosphorus nutrition on plant growth and biological nitrogen fixation in four leguminous plants in the Tribe Genistea. The main objective of the study was to analyze Phosphorus and Nitrogen use efficiency under drought. We also tested for the effects of rhizobial inoculation on plant performance. Plants inoculated with Rhizobium strains isolated from plants of the four species growing in the wild were cropped under controlled conditions in soils with either low P (5 µM) or high P (500 µM). The experiment was replicated in the presence and absence of plant irrigation to test for the effects of drought stress of inoculated and non-inoculated plants under the two P levels of fertilization. Low-P treatments increased nodule production while plant biomass and shoot and root P and N contents where maximum at high P. Low P (5 µM) in the growing media, resulted in greater N accumulated in plants, coupled with greater phosphorus and nitrogen uptake efficiencies. Drought reduced the relative growth rate over two orders of magnitude or more, depending on the combination of plant species and treatment. Genista cinerea had the lowest tolerance to water scarcity, whereas Genista florida and Retama sphaerocarpa were the most resistant species to drought. Drought resistance was enhanced in the inoculated plants. In the four species, and particularly in Echinospartum barnadesii, the inoculation treatment clearly triggered N use efficiency, whereas P use efficiency was greater in the non-inoculated irrigated plants. Nodulation significantly increased in plants in the low P treatments, where plants showed a greater demand for N. The physiological basis for the four species being able to maintain their growth at low P levels and to respond to the greater P supply, is through balanced acquisition of P and N to meet the plants’ nutritional needs.

scholarly journals Regulatory effect of phosphorus and nitrogen on nodulation and plant performance of leguminous shrubs

AoB Plants ◽  
2019 ◽  
Author(s):  
M A Míguez-Montero ◽  
A Valentine ◽  
M A Pérez-Fernández
Keyword(s):  
N Use Efficiency ◽  
P Availability ◽  
Physiological Basis ◽  
P Use Efficiency ◽  
Key Species ◽  
Use Efficiency ◽  
Inoculation Treatment ◽  
The Impact ◽  
P Supply ◽  
N Use

Abstract The impact of phosphorus (P) nutrition on plant growth, symbiotic N2 fixation, and phosphorus and nitrogen use and their assimilation was investigated in four leguminous plants of the genus Cytisus. Plants inoculated with Rhizobium strains isolated from plants of the four species growing in the wild were crop under controlled conditions in soils with either low P (5 µM) or high P (500 µM). The experiment was replicated in the presence and absence of plant irrigation to test for the effects of drought stress of inoculated and non-inoculated plants under the two P levels of fertilization. P-low treatments increased nodule production while plant biomass and shoot and root P and N contents were maximum at sufficient P. The reduction of P in the soil clearly induced biological nitrogen fixation and greater phosphorus and nitrogen uptake efficiencies, as shown by the total N and P accumulated in plants. Similarly, distinct tolerances to drought support this idea. Cytisus balansae had the lowest tolerance to water scarcity. Cytisus multiflorus and Cytisus scoparius were the most resistant species to drought, with this resistance enhanced in the inoculated plants. In the four species, the inoculation treatment clearly enhanced N-use efficiency, whereas P-use efficiency was greater in the non-inoculated plants in the irrigated treatment. With a P-induced demand for N, the plants nodulated prolifically and increased N supply from biological fixation. The physiological basis for N2-fixing C. scoparius and C. striatus maintaining growth at low P supply and responding to greater P supply is through balanced acquisition of P and N for plant demand. Native shrubby legumes are key species in natural ecosystems due to their capability to increase the net N budget in plants and soils and because they modulate the phosphorus availability. Four legumes in the genus Cytisus either native to or commonly represented in the Iberian Peninsula proved to be able shift their N use depending on the soil P availability and on the interactions established with their Bradyrhizobium symbionts. In the four species the inoculation treatment clearly enhanced N-use efficiency and drought tolerance, whereas P-use efficiency was greater in the non-inoculated plants in the irrigated treatment.

scholarly journals Soil microbes weaken the positive effect of an aquatic-terrestrial subsidy on plant performance

2020 ◽  
Author(s):  
Alejandra B Garcia ◽  
Hannah Locke ◽  
Kerri M Crawford
Keyword(s):  
Soil Microbes ◽  
Lake Michigan ◽  
Plant Biomass ◽  
Plant Productivity ◽  
Plant Performance ◽  
Nutrient Inputs ◽  
Positive Effects ◽  
Terrestrial Subsidy ◽  
The Impact ◽  
Terrestrial Subsidies

Abstract Aims Linkages formed through aquatic-terrestrial subsidies can play an important role in structuring communities and mediating ecosystem functions. Aquatic-terrestrial subsidies may be especially important in nutrient-poor ecosystems, such as the freshwater sand dunes surrounding Lake Michigan. Adult midges emerge from Lake Michigan in the spring, swarm to mate, and die. Their carcasses form mounds at the base of plants, where they may increase plant productivity through their nutrient inputs. However, the effect of aquatic-terrestrial subsidies on plant productivity could depend on other biotic interactions. In particular, soil microbes might play a key role in facilitating the conversion of nutrients to plant-available forms or competing for the nutrients by plants. Methods In a greenhouse experiment, we tested how carcasses from lake-emergent midges (Chironomidae) and soil microbes independently and interactively influenced the performance of a common dune grass, Calamovilfa longifolia. To determine whether midges influenced abiotic soil properties, we measured how midge additions influenced soil nutrients and soil moisture. Important findings Midges greatly increased plant biomass, while soil microbes influenced the magnitude of this effect. In the absence of soil microbes plant biomass was 7 times greater with midges than without midges. However, in the presence of soil microbes, plant biomass was only 3 times greater. The effect of midges might be driven by their nutrient inputs into the soil, as midges contained 100 times more N, 10 times more P, and 150 times more K than dune soils did. Our results suggest that soil microbes may be competing with plants for these nutrients. In sum, we found that midges can be an important aquatic-terrestrial subsidy that produces strong, positive effects on plant productivity along the shorelines of Lake Michigan, but that the impact of aquatic-terrestrial subsidies must be considered within the context of the complex interactions that take place within ecological communities.

How to Psychologically Minimize Scratching Impulses

2014 ◽  
Vol 222 (3) ◽  
pp. 140-147 ◽  
Author(s):  
Ariane Sölle ◽  
Theresa Bartholomäus ◽  
Margitta Worm ◽  
Regine Klinger
Keyword(s):  
Cognitive Processes ◽  
Placebo Effect ◽  
Psychological Factors ◽  
Pharmacological Treatments ◽  
Physiological Basis ◽  
Psychological Mechanisms ◽  
Physical Complaints ◽  
Factors Influencing ◽  
The Impact ◽  
Placebo Model

Research in recent years, especially in the analgesic field, has intensively studied the placebo effect and its mechanisms. It has been shown that physical complaints can be efficiently reduced via learning and cognitive processes (conditioning and expectancies). However, despite evidence demonstrating a large variety of physiological similarities between pain and itch, the possible transfer of the analgesic placebo model to itch has not yet been widely discussed in research. This review therefore aims at highlighting potential transfers of placebo mechanisms to itch processes by demonstrating the therapeutic issues in pharmacological treatments for pruritus on a physiological basis and by discussing the impact of psychological mechanisms and psychological factors influencing itch sensations.

Biochemical Composition and Phosphorus Use Efficiency in Some Mixtures

2016 ◽  
Vol 5 (07) ◽  
pp. 4694 ◽  
Author(s):  
Viliana Vasileva ◽  
Anna Ilieva
Keyword(s):  
Perennial Ryegrass ◽  
Biochemical Composition ◽  
Plant Biomass ◽  
Soluble Sugars ◽  
Subterranean Clover ◽  
Water Soluble ◽  
Birdsfoot Trefoil ◽  
Phosphorus Use Efficiency ◽  
Forage Crops ◽  
Use Efficiency

In pot trial the biochemical composition and phosphorus use efficiency of birdsfoot trefoil, sainfoin and subterranean clover grown pure and in mixtures with perennial ryegrass in the next ratios were studied in the Institute of Forage Crops, Pleven, Bulgaria: birdsfoot trefoil + perennial ryegrass (50:50%); sainfoin + perennial ryegrass (50:50%); subterranean clover + perennial ryegrass (50:50%); birdsfoot trefoil + subterranean clover + perennial ryegrass (33:33:33%); sainfoin + subterranean clover + perennial ryegrass (33:33:33%). The highest crude protein content was found in the aboveground mass of birdsfoot trefoil (19.17%) and sainfoin (19.30%). The water soluble sugars contents in mixtures was found higher compared to the pure grown legumes. Birdsfoot trefoil showed the highest phosphorus use efficiency for plant biomass accumulation and nodules formation. In mixtures the phosphorus use efficiency was found be higher as compared to the same in pure grown legumes.

Impacts of separate rejection water treatment on the overall plant performance

2003 ◽  
Vol 48 (4) ◽  
pp. 139-146 ◽  
Author(s):  
B. Wett ◽  
J. Alex
Keyword(s):  
Water Treatment ◽  
Treatment Plant ◽  
Operating Experience ◽  
Plant Performance ◽  
High Tech ◽  
State Variables ◽  
Total N ◽  
Unit Process ◽  
Innovative Tool ◽  
The Impact

A separate rejection water treatment appears as a high-tech unit process which might be recommendable only for specific cases of an upgrading of an existing wastewater treatment plant. It is not the issue of this paper to consider a specific separate treatment process itself but to investigate the influence of such a process on the overall plant performance. A plant-wide model has been applied as an innovative tool to evaluate effects of the implemented sidestream strategy on the mainstream treatment. The model has been developed in the SIMBA environment and combines acknowledged mathematical descriptions of the activated sludge process (ASM1) and the anaerobic mesophilic digestion (Siegrist model). The model's calibration and validation was based on data from 5 years of operating experience of a full-scale rejection water treatment. The impact on the total N-elimination efficiency is demonstrated by detailed nitrogen mass flow schemes including the interactions between the wastewater and the sludge lane. Additionally limiting conditions due to dynamic N-return loads are displayed by the model's state variables.

scholarly journals The environmental and ecological determinants of elevated Ross River Virus exposure in koalas residing in urban coastal landscapes

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Brian J. Johnson ◽  
Amy Robbins ◽  
Narayan Gyawali ◽  
Oselyne Ong ◽  
Joanne Loader ◽  
...  
Keyword(s):  
Animal Movement ◽  
Ross River Virus ◽  
Mosquito Vector ◽  
Large Numbers ◽  
Culex Annulirostris ◽  
Coastal Landscapes ◽  
In The Wild ◽  
Virus Exposure ◽  
Elevated Exposure ◽  
The Impact

AbstractKoala populations in many areas of Australia have declined sharply in response to habitat loss, disease and the effects of climate change. Koalas may face further morbidity from endemic mosquito-borne viruses, but the impact of such viruses is currently unknown. Few seroprevalence studies in the wild exist and little is known of the determinants of exposure. Here, we exploited a large, spatially and temporally explicit koala survey to define the intensity of Ross River Virus (RRV) exposure in koalas residing in urban coastal environments in southeast Queensland, Australia. We demonstrate that RRV exposure in koalas is much higher (> 80%) than reported in other sero-surveys and that exposure is uniform across the urban coastal landscape. Uniformity in exposure is related to the presence of the major RRV mosquito vector, Culex annulirostris, and similarities in animal movement, tree use, and age-dependent increases in exposure risk. Elevated exposure ultimately appears to result from the confinement of remaining coastal koala habitat to the edges of permanent wetlands unsuitable for urban development and which produce large numbers of competent mosquito vectors. The results further illustrate that koalas and other RRV-susceptible vertebrates may serve as useful sentinels of human urban exposure in endemic areas.

scholarly journals Does the Construction and Operation of High-Speed Rail Improve Urban Land Use Efficiency? Evidence from China

Land ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 303
Author(s):  
Xinhai Lu ◽  
Yifeng Tang ◽  
Shangan Ke
Keyword(s):  
Economic Growth ◽  
Land Use ◽  
High Speed ◽  
Urban Land ◽  
Urban Land Use ◽  
Western China ◽  
High Speed Rail ◽  
Land Use Efficiency ◽  
Use Efficiency ◽  
The Impact

The construction and operation of high-speed rail (HSR) has become an important policy for China to achieve efficiency and fairness and promote high-quality economic growth. HSR promotes the flow of production factors such as labor and capital and affects economic growth, and may further affect urban land use efficiency (ULUE). To explore the impact of HSR on ULUE, this paper uses panel data of 284 cities in China from 2005 to 2018, and constructs Propensity Score Matching-Differences in Differences model to evaluate the effect of HSR on ULUE. The result of entire China demonstrates that the HSR could significantly improves the ULUE. Meanwhile, this paper also considers the heterogeneity of results caused by geographic location, urban levels and scales. It demonstrates that the HSR has a significantly positive effect on ULUE of Eastern, Central China, and large-sized cities. However, in Western China, in medium-sized, and small-sized cities, the impact of HSR on ULUE is not significant. This paper concludes that construction and operation of HSR should be linked to urban development planning and land use planning. Meanwhile, the cities with different geographical locations and scales should take advantage of HSR to improve ULUE and promote urban coordinated development.

Labour-use Efficiency of Assam Gramin Vikash Bank: Branch- and District-level Analysis

2021 ◽  
pp. 232102222110243
Author(s):  
Mohuya Deb Purkayastha ◽  
Joyeeta Deb ◽  
Ram Pratap Sinha
Keyword(s):  
Efficiency Score ◽  
Significant Variable ◽  
Data Envelopment ◽  
Tobit Regression ◽  
Second Stage ◽  
Time Period ◽  
Use Efficiency ◽  
The Mean ◽  
The Impact ◽  
Observation Period

The present study estimated labour-use efficiency of 48 branches of Assam Gramin Vikash Bank at its branch level, covering three districts of Barak Valley, which falls under Silchar region of the bank for the time period from 2010–2011 to 2017–2018. The study applied data envelopment analysis for estimating labour-use efficiency. In the second stage, the study applied censored Tobit regression for determining the impact of several contextual variables on efficiency. The study reveals that the mean labour-use efficiency score of the selected branches is 76% when averaged for the in-sample branches over the observation period. Results of the Tobit regression identified cluster 2 and total business of the branches as the significant factors for determining efficiency and the number of employees as a significant variable influencing inefficiency. JEL Classifications: G2, G20, G21, J3

Can repeated soil amendment with biogas digestates increase soil suppressiveness toward non-specific soil-borne pathogens in agricultural lands?

2020 ◽  
pp. 1-12
Author(s):  
L. M. Manici ◽  
F. Caputo ◽  
G. A. Cappelli ◽  
E. Ceotto
Keyword(s):  
Plant Growth ◽  
Biomass Production ◽  
Soil Amendment ◽  
Plant Biomass ◽  
Amended Soils ◽  
Soil Suppressiveness ◽  
Soil Microbial ◽  
Soil Borne Pathogens ◽  
The Impact ◽  
Plant Biomass Production

Abstract Soil suppressiveness which is the natural ability of soil to support optimal plant growth and health is the resultant of multiple soil microbial components; which implies many difficulties when estimating this soil condition. Microbial benefits for plant health from repeated digestate applications were assessed in three experimental sites surrounding anaerobic biogas plants in an intensively cultivated area of northern Italy. A 2-yr trial was performed in 2017 and 2018 by performing an in-pot plant growth assay, using soil samples taken from two fields for each experimental site, of which one had been repeatedly amended with anaerobic biogas digestate and the other had not. These fields were similar in management and crop sequences (maize was the recurrent crop) for the last 10 yr. Plant growth response in the bioassay was expressed as plant biomass production, root colonization frequency by soil-borne fungi were estimated to evaluate the impact of soil-borne pathogens on plant growth, abundance of Pseudomonas and actinomycetes populations in rhizosphere were estimated as beneficial soil microbial indicators. Repeated soil amendment with digestate increased significantly soil capacity to support plant biomass production as compared to unamended control in both the years. Findings supported evidence that this increase was principally attributable to a higher natural ability of digestate-amended soils to reduce root infection by saprophytic soil-borne pathogens whose inoculum was increased by the recurrent maize cultivation. Pseudomonas and actinomycetes were always more abundant in digestate-amended soils suggesting that both these large bacterial groups were involved in the increase of their natural capacity to control soil-borne pathogens (soil suppressiveness).

scholarly journals Physiological Basis of Combined Stress Tolerance to Low Phosphorus and Drought in a Diverse Set of Mungbean Germplasm

Agronomy ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 99
Author(s):  
Surendra Kumar Meena ◽  
Renu Pandey ◽  
Sandeep Sharma ◽  
Gayacharan ◽  
Tarun Kumar ◽  
...  
Keyword(s):  
Principal Component ◽  
Stability Index ◽  
P Uptake ◽  
Combined Stress ◽  
Physiological Basis ◽  
Low Phosphorus ◽  
Relative Water ◽  
Use Efficiency ◽  
Organic Acid Exudation ◽  
Physiological Markers

To understand the physiological basis of tolerance to combined stresses to low phosphorus (P) and drought in mungbean (Vignaradiata (L.) R. Wilczek), a diverse set of 100 accessions were evaluated in hydroponics at sufficient (250 μM) and low (3 μM) P and exposed to drought (dehydration) stress. The principal component analysis and ranking of accessions based on relative values revealed that IC280489, EC397142, IC76415, IC333090, IC507340, and IC121316 performed superior while IC119005, IC73401, IC488526, and IC325853 performed poorly in all treatments. Selected accessions were evaluated in soil under control (sufficient P, irrigated), low P (without P, irrigated), drought (sufficient P, withholding irrigation), and combined stress (low P, withholding irrigation). Under combined stress, a significant reduction in gas exchange traits (photosynthesis, stomatal conductance, transpiration, instantaneous water use efficiency) and P uptake in seed and shoot was observed under combined stress as compared to individual stresses. Among accessions, IC488526 was most sensitive while IC333090 and IC507340 exhibited tolerance to individual or combined stress. The water balance and low P adaptation traits like membrane stability index, relative water content, specific leaf weight, organic acid exudation, biomass, grain yield, and P uptake can be used as physiological markers to evaluate for agronomic performance. Accessions with considerable tolerance to low P and drought stress can be either used as ‘donors’ in Vigna breeding program or cultivated in areas with limited P and water availability or both.

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