Soil Chemical and Microbiological Properties Are Changed by Long-Term Chemical Fertilizers That Limit Ecosystem Functioning

Although the effects of fertilization and microbiota on plant growth have been widely studied, our understanding of the chemical fertilizers to alter soil chemical and microbiological properties in woody plants is still limited. The aim of the present study is to investigate the impact of long-term application of chemical fertilizers on chemical and microbiological properties of root-associated soils of walnut trees. The results show that soil organic matter (OM), pHkcl, total nitrogen (TN), nitrate-nitrogen (NO3−), and total phosphorus (TP) contents were significantly higher in non-fertilized soil than after chemical fertilization. The long-term fertilization led to excessive ammonium-nitrogen (NH4+) and available phosphorus (AP) residues in the cultivated soil, among which NH4+ resulted in soil acidification and changes in bacterial community structure, while AP reduced fungal diversity. The naturally grown walnut trees led to an enrichment in beneficial bacteria such as Burkholderia, Nitrospira, Pseudomonas, and Candidatus_Solibacter, as well as fungi, including Trichoderma, Lophiostoma, Phomopsis, Ilyonectria, Purpureocillium, Cylindrocladiella, Hyalorbilia, Chaetomium, and Trichoglossum. The presence of these bacterial and fungal genera that have been associated with nutrient mobilization and plant growth was likely related to the higher soil OM, TN, NO3−, and TP contents in the non-fertilized plots. These findings highlight that reduced chemical fertilizers and organic cultivation with beneficial microbiota could be used to improve economic efficiency and benefit the environment in sustainable agriculture.

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Improvement Growth, Yield, and Seed Quality of Pea Plants Using Glass Fertilizers and Bio-Fertilizers.

10.21203/rs.3.rs-634380/v1 ◽

2021 ◽

Author(s):

Eman G. Sayed ◽

Mona A. Ouis

Keyword(s):

Plant Growth ◽

Rhizobium Leguminosarum ◽

Field Experiments ◽

Seed Quality ◽

Growth Yield ◽

Control Treatment ◽

Chemical Fertilizers ◽

Yield Attributes ◽

The Impact

Abstract A new glass fertilizer (GF) system of main composition 60P2O5.30K2O.3.5ZnO. 3.5MnO.3Fe2O3 was developed in response to the needs of pea plants with bio-fertilizers (Rhizobium leguminosarum. Bv.vicieae, Bacillus megaterium var phosphaticum, Bacillus circulans).GF was prepared by the traditional melt quenching technique at 1150°C. Characterization of prepared system was done using FTIR spectra before and after immersion in a simulated actual agriculture medium like 2% citric acid and distilled water. During two winter seasons, two successful field experiments were conducted at Cairo University's Eastern Farm to determine the impact of chemical, glass, and bio-fertilizers on plant growth, yield attributes, and seed quality of pea plant. Control treatment were without any addition of recommended chemical fertilizers and other treatments were full dose of recommended chemical fertilizers (100%RDF), glass fertilizers at rate 60 kg fed− 1, Glass fertilizers at rate30 kg fed− 1, 50% RDF ,100%RDF + bio-fertilizers, Glass fertilizers at rate 60 kg fed− 1 + bio-fertilizers, glass fertilizers at rate 30 kg fed− 1+ bio-fertilizers, 50%RDF + bio-fertilizers. Plots received 60 kg fed− 1 glass fertilizers + bio-fertilizers show the highest significant increment in plant growth, number and weight of pods plant− 1, number of grain pods− 1, grain yield, biological yield, P%, k% in pea leaves and quality of pea seeds compared with plots without any addition (control) in both seasons.

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Long-term mineral fertilization impact on chemical and microbiological properties of soil and Miscanthus × giganteus yield

Plant Soil and Environment ◽

10.17221/890/2013-pse ◽

2014 ◽

Vol 60 (No. 3) ◽

pp. 117-122 ◽

Cited By ~ 5

Author(s):

W. Stępień ◽

Górska EB ◽

S. Pietkiewicz ◽

Kalaji MH

Keyword(s):

Heterotrophic Bacteria ◽

Growth And Yield ◽

Mineral Fertilization ◽

Soil Microbial ◽

Miscanthus Giganteus ◽

Microbial Characteristics ◽

The Impact ◽

Properties Of Soil ◽

Microbiological Properties

This experimental work was undertaken to assess the effect of various fertilization regimes (CaNPK, NPK, CaPK, CaPN, CaKN and Ca) and different soil properties on growth and yield of Miscanthus plants and to check the impact of this plant on soil microbial characteristics. Field experiment was set up in 2003 on a long-term fertilization experiment, which had been established since 1923. Miscanthus giganteus response to high soil acidity and deficiency of N, P and K was investigated. Some physico-chemical and microbiological properties of soil samples were estimated and microbial characteristics of soil were conducted to investigate the number of the following microorganisms: heterotrophic bacteria, microscopic fungi, and some diazotrophic bacteria. Obtained results showed that, the highest yield of Miscanthus was obtained from the field fertilized with the CaNPK; while the lowest one was found for plants grown without nitrogen (CaPK). The high acidity of soil and small amount of phosphorus did not affect the yields in the NPK and CaKN combinations as compared with CaNPK one. The experiments showed that Miscanthus giganteus responded positively to mineral fertilization, especially with nitrogen. The rhizosphere of Miscanthus plants provides a suitable environment for the growth and development of microorganisms, in contrast to the non-rhizosphere zone.

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Effect of Pasture Management System Change on In-Season Inorganic Nitrogen Pools and Heterotrophic Microbial Communities

Agronomy ◽

10.3390/agronomy10050724 ◽

2020 ◽

Vol 10 (5) ◽

pp. 724

Author(s):

Maciej Musiał ◽

Jan Kryszak ◽

Witold Grzebisz ◽

Agnieszka Wolna-Maruwka ◽

Remigiusz Łukowiak

Keyword(s):

Management System ◽

Poa Pratensis ◽

Inorganic Nitrogen ◽

Dactylis Glomerata ◽

Available Phosphorus ◽

Pasture Management ◽

Dactylis Glomerata L ◽

Grass Sward ◽

The Impact

It has been assumed that the system of long-term pasture management exerts a significant impact on the soil microorganisms count, subsequently affecting the availability of mineral nitrogen (Nmin). This hypothesis was tested in a three-year experiment on a long-term pasture with two distinct systems of grass sward management, i.e., grazing and mowing. Mowing significantly increased the microorganisms count by 13%, 28%, 86%, and 2% for eubacteria (EU), actinobacteria (AC), molds (MO), and Azotobacter (AZ), respectively. The main reason was drought in 2006, which resulted in the domination of Dactylis glomerata L. in the grass sward, instead of Lolimum perenne L. and Poa pratensis L. The content of Nmin decreased through the vegetative growing season, reaching its lowest value after the 3rd grazing cycle. The impact of microorganisms on the Nmin pools increased in the order: molds < eubacteria < actinobacteria. The count of actinobacteria in the alkaline organic soil increased in response to drought, contribution of Dactylis glomerata L. in the sward, and the shortage of available phosphorus. The sound pasture management system is possible by introducing alternate grazing and mowing cycles. The core of sustainability is the enhanced activity of actinobacteria after changing the system from grazed into mowed.

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Soil phosphorus, biology and time: A case for publishing inconclusive data, and the undeniable relevance of tennis balls

10.5194/egusphere-egu21-16487 ◽

2021 ◽

Author(s):

Phil Haygarth ◽

Malika Mezeli ◽

Timothy George ◽

Roy Neilson ◽

Martin Blackwell

Keyword(s):

Plant Growth ◽

Trophic Interactions ◽

Meta Analysis ◽

Soil Phosphorus ◽

Plant Responses ◽

Soil P ◽

The Impact ◽

Time Point

The association of microorganisms and soil nutrient cycles has been observed for over 200 years, and their importance in the soil phosphorus (P) cycle is well documented. In-soil trophic interactions between bacteria and bacterivorous nematodes have been implicated in increased plant access to soil organic P (Po).However, the existing data remains inconclusive and lacks detail and predictability.&#160; This work aimed to (1) assess the impact of nematodes as an additional trophic-level on Po use by plants in arable systems and (2) further understand the mechanisms of in-soil trophic interactions in improving plant acquisition of Po. To address these aims criteria based meta-analysis, glasshouse plant growth trials, in vitro and soil, and long term experimental (LTE) platforms were used.&#160; Results led to the conclusion that nematodes did not improve plant acquisition of Po per se. Time, soil P concentration and soil biological community composition had significant impacts on plant response. Although these factors were identified in two contrasting studies, their impacts on plant responses were stochastic. Complexity, which describes the average number of trophic links per species, framed an understanding of these data where they evaded predictability, specifically when considering the temporal nature of these relationships. For example, data from the meta-analysis and the plant growth trials demonstrated it was not simply the additive effect of the number of species or the addition of a specific species which resulted in predictable plant P responses.&#160; Nematode community analysis from the LTE&#8217;s yielded characteristics indicative of stability in the biotic component of systems previously considered disturbed (arable). This exposed the question of the nature of disturbance (whether natural or anthropogenic). Additionally, it highlighted the importance of which successional time-point was being studied and the impact this has on the data captured.&#160; Data collected from this long-term experiment, plant growth trials and the meta-analysis highlights the importance of the temporal resolution, and the time-point at which we are observing these dynamic systems. It is argued that in-conclusive or negative results could represent true details of these systems, where they represent points of transition between stable and/or predictable states and a usual characteristic of the complex system.&#160; Therefore, inconclusive data should not be omitted from the research library, exclusion of such data could lead to incomplete observations and incorrect assumptions. Better practices should be designed and implemented to ensure publication bias is not a barrier to our understanding of these systems.

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Rock Phosphate-Enriched Compost in Combination with Rhizobacteria; A Cost-Effective Source for Better Soil Health and Wheat (Triticum aestivum) Productivity

Agronomy ◽

10.3390/agronomy10091390 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1390

Author(s):

Motsim Billah ◽

Matiullah Khan ◽

Asghari Bano ◽

Sobia Nisa ◽

Ahmad Hussain ◽

...

Keyword(s):

Microbial Biomass ◽

Rock Phosphate ◽

Phosphorus Deficiency ◽

Poultry Litter ◽

Biochemical Properties ◽

Available Phosphorus ◽

Pseudomonas Sp ◽

Chemical Fertilizers ◽

Seed Inoculation ◽

The Impact

Organic materials from various sources have been commonly adopted as soil amendments to improve crop productivity. Phosphorus deficiency and fixation in alkaline calcareous soils drives a reduction in crop production. A two-year field experiment was conducted to evaluate the impact of rock phosphate enriched composts and chemical fertilizers both individually and in combination with plant growth promoting rhizobacteria (PGPR) on wheat productivity and soil chemical and biological and biochemical properties. The present study demonstrates significant increments in crop agronomic and physiological parameters with Pseudomonas sp. inoculated RPEC1 (rock phosphate + poultry litter + Pseudomonas sp.) over the un-inoculated untreated control. However, among all other treatments i.e., RPEC2 (rock phosphate + poultry litter solubilized with Proteus sp.), RPC (rock phosphate + poultry litter), HDP (half dose inorganic P from Single Super Phosphate-SSP 18% P2O5) and SPLC (poultry litter only); RPEC1 remained the best by showing increases in soil chemical properties (available phosphorus, nitrate nitrogen, extractable potassium), biochemical properties (alkaline phosphatase activity) and biological properties (microbial biomass carbon and microbial biomass phosphorus). Economic analysis in terms of Value Cost Ratio (VCR) showed that the seed inoculation with Pseudomonas sp. in combination with RPEC1 gave maximum VCR (3.23:1) followed by RPEC2 (2.61:1), FDP (2.37:1), HDP (2.05:1) and SPLC (2.03:1). It is concluded that inoculated rock phosphate (RP) enriched compost (RPEC1) can be a substitute to costly chemical fertilizers and seed inoculation with Pseudomonas sp. may further increase the efficiency of composts.

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Suppressed, but Not Forgotten

Swiss Journal of Psychology ◽

10.1024/1421-0185/a000033 ◽

2011 ◽

Vol 70 (1) ◽

pp. 5-11 ◽

Cited By ~ 8

Author(s):

Beat Meier ◽

Anja König ◽

Samuel Parak ◽

Katharina Henke

Keyword(s):

Memory Trace ◽

Thought Suppression ◽

Test Phase ◽

Indirect Test ◽

Final Test ◽

Test Experiment ◽

And Control ◽

Cue Words ◽

The Impact

This study investigates the impact of thought suppression over a 1-week interval. In two experiments with 80 university students each, we used the think/no-think paradigm in which participants initially learn a list of word pairs (cue-target associations). Then they were presented with some of the cue words again and should either respond with the target word or avoid thinking about it. In the final test phase, their memory for the initially learned cue-target pairs was tested. In Experiment 1, type of memory test was manipulated (i.e., direct vs. indirect). In Experiment 2, type of no-think instructions was manipulated (i.e., suppress vs. substitute). Overall, our results showed poorer memory for no-think and control items compared to think items across all experiments and conditions. Critically, however, more no-think than control items were remembered after the 1-week interval in the direct, but not in the indirect test (Experiment 1) and with thought suppression, but not thought substitution instructions (Experiment 2). We suggest that during thought suppression a brief reactivation of the learned association may lead to reconsolidation of the memory trace and hence to better retrieval of suppressed than control items in the long term.

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