Biostimulant Effects of Micro Carbon Technology (MCT®)-Based Fertilizers on Soil and Capsicum annuum Culture in Growth Chamber and Field

Due to the environmental issues that conventional fertilization is causing, biostimulants are proposed as environmentally friendly alternative for crop nutrition in agriculture. The aim of this study was to determine the effects of new Micro Carbon Technology (MCT®) fertilizers with biostimulant activity based on humic acids biologically digested from leonardite on pepper plant growth in three different soils with different textures. The assays were performed under controlled conditions in a growth chamber and in commercial greenhouses in Spain. The effects on soil were analyzed after the addition of the fertilizers by microbial respiration and enzymatic activities (hydrolase, dehydrogenase and urease). For the plant assays, biometric parameters (fresh weight and fruit hardness) and foliar analysis (chlorophyll indices and nutrients) were evaluated. Under controlled conditions, the use of these biostimulants resulted in a greater soil microbial activity in a 24 h interval with increased soil enzymatic activity. In plants, a positive correlation was found between fertilizers with biostimulant activity and Dualex indices of leaves and content of macronutrients Ca and Mg. In commercial greenhouses, the fertilizers with biostimulant activity strongly depended on the soil texture. In conclusion, these products have real potential to replace conventional fertilizers in commercial production fields.

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The Chemical Composition of Biogas Digestates Determines Their Effect on Soil Microbial Activity

Agriculture ◽

10.3390/agriculture10060244 ◽

2020 ◽

Vol 10 (6) ◽

pp. 244 ◽

Cited By ~ 2

Author(s):

Kerstin Nielsen ◽

Christina-Luise Roß ◽

Marieke Hoffmann ◽

Andreas Muskolus ◽

Frank Ellmer ◽

...

Keyword(s):

Soil Respiration ◽

Microbial Activity ◽

Laboratory Experiments ◽

Lignin Content ◽

Control Level ◽

Carbon Mineralization ◽

Soil Microbial Activity ◽

Short Term ◽

Soil Microbial ◽

Different Soils

Digestates are commonly used as organic inputs in agriculture. This study aimed to answer four questions: (1) What are the immediate and longer-term impacts of digestates on soil microbial activity?; (2) How much of the digestates’ carbon is mineralized within the first months? (3) How do the nitrogen, lignin, cellulose, and hemicellulose contents of digestates influence microbial activity and carbon mineralization? (4) How does the soil type influence mineralization? To investigate this, dehydrogenase activity (DHA) was measured in a field trial and in laboratory experiments with five digestates (DGs), cattle slurry, and cattle manure. DHA measurements were supplemented with soil respiration experiments using two different soils. DHA was significantly increased by all organic inputs, but decreased back to the control level within seven months under field conditions. Twenty percent to 44% of the organic carbon (Corg) in the digestates was converted to CO2 after 178 days. Soil respiration was significantly negatively correlated to lignin content (r = −0.82, p < 0.01) and not correlated to nitrogen, cellulose, or hemicellulose content. On the basis of equal carbon application, slurry promoted soil respiration and DHA more strongly than digestates in the short term.

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Efficacy of Different Forms of Green Manure Crops to Reduce Verticillium dahliae in Different Soils

Global Journal of Agricultural Innovation Research & Development ◽

10.15377/2409-9813.2021.08.15 ◽

2021 ◽

Vol 8 ◽

pp. 191-205

Author(s):

Swann Dalbard ◽

Vincent V. Michel

Keyword(s):

Verticillium Dahliae ◽

Green Manure ◽

Sandy Loam ◽

Indian Mustard ◽

Soil Microbial Activity ◽

Glucosinolate Content ◽

Soil Microbial ◽

Loam Soil ◽

Green Manure Crops ◽

Different Soils

The efficacy of green manure crops to reduce the number of Verticillium dahliae microsclerotia in different soils was investigated. Green manures tested were Indian mustard with a high glucosinolate content and sorghum-sudangrass as biocidal plants, and Indian mustard with a low glucosinolate content and rye as non-biocidal plants. The green manure plants were applied in fresh, dried, and ensilaged form. When applied as fresh plants, the glucosinolate content determining the biocidal activity of Indian mustard was only important in loam soil but not in sandy loam soil. In the latter soil, the non-biocidal rye had significantly higher efficacy than the Indian mustard. Volatiles released by fresh and dried, but not ensilaged, Indian mustard with a high glucosinolate content strongly decreased the number of living V. dahliae microsclerotia. When the same green manure crops were added to sandy loam and clay loam soil, the effect of the high glucosinolate content Indian mustard in fresh and dried form disappeared, whereas the ensilaged green manure crops had the highest efficacy. This effect was based on the increase of the soil microbial activity and the Streptomyces population size, which were negatively correlated with the number of living V. dahliae microsclerotia in the soil.

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Effect of Water Potential, Temperature, and Soil Microbial Activity on Release of Starch‐Encapsulated Atrazine and Alachlor

Journal of Environmental Quality ◽

10.2134/jeq1992.00472425002100030013x ◽

1992 ◽

Vol 21 (3) ◽

pp. 382-386 ◽

Cited By ~ 15

Author(s):

Brian J. Wienhold ◽

Timothy J. Gish

Keyword(s):

Water Potential ◽

Microbial Activity ◽

Potential Temperature ◽

Soil Microbial Activity ◽

Soil Microbial ◽

Effect Of Water

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Forest defoliator pests alter carbon and nitrogen cycles

Royal Society Open Science ◽

10.1098/rsos.160361 ◽

2016 ◽

Vol 3 (10) ◽

pp. 160361 ◽

Cited By ~ 12

Author(s):

Anne l-M-Arnold ◽

Maren Grüning ◽

Judy Simon ◽

Annett-Barbara Reinhardt ◽

Norbert Lamersdorf ◽

...

Keyword(s):

Climate Change ◽

Leaf Litter ◽

Soil Microbial Activity ◽

Quercus Petraea ◽

Oak Forests ◽

Operophtera Brumata ◽

Winter Moth ◽

Carbon And Nitrogen ◽

Soil Microbial ◽

C And N

Climate change may foster pest epidemics in forests, and thereby the fluxes of elements that are indicators of ecosystem functioning. We examined compounds of carbon (C) and nitrogen (N) in insect faeces, leaf litter, throughfall and analysed the soils of deciduous oak forests ( Quercus petraea L.) that were heavily infested by the leaf herbivores winter moth ( Operophtera brumata L.) and mottled umber ( Erannis defoliaria L.). In infested forests, total net canopy-to-soil fluxes of C and N deriving from insect faeces, leaf litter and throughfall were 30- and 18-fold higher compared with uninfested oak forests, with 4333 kg C ha −1 and 319 kg N ha −1 , respectively, during a pest outbreak over 3 years. In infested forests, C and N levels in soil solutions were enhanced and C/N ratios in humus layers were reduced indicating an extended canopy-to-soil element pathway compared with the non-infested forests. In a microcosm incubation experiment, soil treatments with insect faeces showed 16-fold higher fluxes of carbon dioxide and 10-fold higher fluxes of dissolved organic carbon compared with soil treatments without added insect faeces (control). Thus, the deposition of high rates of nitrogen and rapidly decomposable carbon compounds in the course of forest pest epidemics appears to stimulate soil microbial activity (i.e. heterotrophic respiration), and therefore, may represent an important mechanism by which climate change can initiate a carbon cycle feedback.

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Carbon limitation overrides acidification in mediating soil microbial activity to nitrogen enrichment in a temperate grassland

Global Change Biology ◽

10.1111/gcb.15819 ◽

2021 ◽

Author(s):

Qiushi Ning ◽

Stephan Hättenschwiler ◽

Xiaotao Lü ◽

Paul Kardol ◽

Yunhai Zhang ◽

...

Keyword(s):

Microbial Activity ◽

Soil Microbial Activity ◽

Temperate Grassland ◽

Carbon Limitation ◽

Nitrogen Enrichment ◽

Soil Microbial

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Effect of Plant Growth Regulators on Protease Activity in Forest Floor of Norway Spruce Stand

Forests ◽

10.3390/f12060665 ◽

2021 ◽

Vol 12 (6) ◽

pp. 665

Author(s):

Ladislav Holik ◽

Jiří Volánek ◽

Valerie Vranová

Keyword(s):

Organic Matter ◽

Proteolytic Activity ◽

Protease Activity ◽

Forest Floor ◽

Soil Microbial Activity ◽

Inhibitory Effects ◽

Chlorocholine Chloride ◽

Soil Microbial ◽

Native Soil ◽

Transformation Processes

Soil proteases are involved in organic matter transformation processes and, thus, influence ecosystem nutrient turnovers. Phytohormones, similarly to proteases, are synthesized and secreted into soil by fungi and microorganisms, and regulate plant rhizosphere activity. The aim of this study was to determine the effect of auxins, cytokinins, ethephon, and chlorocholine chloride on spruce forest floor protease activity. It was concluded that the presence of auxins stimulated native proteolytic activity, specifically synthetic auxin 2-naphthoxyacetic acid (16% increase at added quantity of 5 μg) and naturally occurring indole-3-acetic acid (18%, 5 μg). On the contrary, cytokinins, ethephon and chlorocholine chloride inhibited native soil protease activity, where ethephon (36% decrease at 50 μg) and chlorocholine chloride (34%, 100 μg) showed the highest inhibitory effects. It was concluded that negative phytohormonal effects on native proteolytic activity may slow down organic matter decomposition rates and hence complicate plant nutrition. The study enhances the understanding of rhizosphere exudate effects on soil microbial activity and soil nitrogen cycle.

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Effects of Monoculture, Crop Rotation, and Soil Moisture Content on Selected Soil Physicochemical and Microbial Parameters in Wheat Fields

Applied and Environmental Soil Science ◽

10.1155/2012/593623 ◽

2012 ◽

Vol 2012 ◽

pp. 1-13 ◽

Cited By ~ 7

Author(s):

A. Marais ◽

M. Hardy ◽

M. Booyse ◽

A. Botha

Keyword(s):

Soil Moisture ◽

Microbial Communities ◽

Crop Rotation ◽

Management Practices ◽

Agricultural Soils ◽

Soil Microbial Communities ◽

Soil Microbial Activity ◽

Most Probable Number ◽

Probable Number ◽

Soil Microbial

Different plants are known to have different soil microbial communities associated with them. Agricultural management practices such as fertiliser and pesticide addition, crop rotation, and grazing animals can lead to different microbial communities in the associated agricultural soils. Soil dilution plates, most-probable-number (MPN), community level physiological profiling (CLPP), and buried slide technique as well as some measured soil physicochemical parameters were used to determine changes during the growing season in the ecosystem profile in wheat fields subjected to wheat monoculture or wheat in annual rotation with medic/clover pasture. Statistical analyses showed that soil moisture had an over-riding effect on seasonal fluctuations in soil physicochemical and microbial populations. While within season soil microbial activity could be differentiated between wheat fields under rotational and monoculture management, these differences were not significant.

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Decrease in soil microbial activity and biomasses owing to nitrogen amendments

Canadian Journal of Microbiology ◽

10.1139/m83-231 ◽

1983 ◽

Vol 29 (11) ◽

pp. 1500-1506 ◽

Cited By ~ 175

Author(s):

B. Söderström ◽

E. Bååth ◽

B. Lundgren

Keyword(s):

Respiration Rate ◽

Laboratory Experiments ◽

Coniferous Forest ◽

Soil Microbial Activity ◽

Urea Treatment ◽

Soil Microbial ◽

Respiration Rates ◽

Nitrate Addition ◽

Transitory Effect ◽

Forest Podzols

Microbial biomass and soil respiration rate decreased after application of 150 kg NH4NO3–N∙ha−1 to different coniferous forest podzols. The decrease was already found 3 months after fertilization and was still evident after 3–5 years. Changes in pH, organic matter, or water content in the soils could not explain the decreases. In laboratory experiments, several unfertilized forest soils were treated with 2 mg of NH4NO3–N or of urea–nitrogen∙g wet soil−1. The ammonium nitrate addition resulted in severe depressions of the respiration rates during and up to 175 days of incubation and the decrease was evident after about 1 week. The urea treatment initially increased the respiration rate of the soils, but this appeared to be a transitory effect.

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