scholarly journals Traffic soil compaction of an oxisol related to soybean development and yield

2007 ◽  
Vol 64 (6) ◽  
pp. 608-615 ◽  
Author(s):  
Amauri Nelson Beutler ◽  
José Frederico Centurion ◽  
Maria Aparecida Pessoa da Cruz Centurion ◽  
Onã da Silva Freddi ◽  
Eurico Lucas de Sousa Neto ◽  
...  
Keyword(s):  
Root Development ◽  
Soil Compaction ◽  
Penetration Resistance ◽  
Soil Bulk Density ◽  
Soil Samples ◽  
The Other ◽  
Undisturbed Soil ◽  
Compacted Soil ◽  
Randomized Design ◽  
Completely Randomized Design

Excessive traffic on the soil may affect soybean development. This research was carried out to evaluate soybean root development and grain yield under compacted soil, in an Oxisol. The following traffic treatments were used: T0 = no traffic; T1* = 1 passage of a 4 t tractor; and, T1, T2, T4 and T6, respectively for 1, 2, 4 and 6 passages of an 11 t tractor on the same location, each besides the other. After compaction, soybean [Glycine max cv. MG/BR 46 (Conquista)] was cultivated. The experiment was arranged in a completely randomized design, with six compaction levels and four replicates (plots of 9.0 m²). Undisturbed soil samples were collected in the layers 0.03-0.06, 0.08-0.11, 0.15-0.18 and 0.22-0.25 m, for physical analyses. Root analyses were performed at layers of 0.0-0.10, 0.10-0.15 and 0.20-0.25 m. Soil compaction decreased deep root development and did not affect root amount, but its distribution. Yield decreased at the penetration resistance of 2.33 MPa or higher, and soil bulk density of 1.51 Mg m-3 or higher.

scholarly journals Kenaf (Hibiscus cannabinus L.) as a remedy to oxisol contaminated with different mercury (Hg2+) concentrations

2021 ◽  
pp. 780-786
Author(s):  
Letícia Fernanda Lavezzo ◽  
Denise de Lima Dias Delarica ◽  
Anne Hélène Fostier ◽  
Everlon Cid Rigobelo ◽  
Roberta Souto Carlos ◽  
...  
Keyword(s):  
Transfer Factor ◽  
Absorption Spectrometry ◽  
Soil Samples ◽  
Hibiscus Cannabinus ◽  
The Other ◽  
Controlled Environment ◽  
Randomized Design ◽  
Total Hg ◽  
Completely Randomized Design ◽  
Soil Hg

We evaluated Hibiscus cannabinus (kenaf) to remedy oxisol contaminated with Hg2 + potential. The study was conducted in a controlled environment in pots with soil contaminated with HgCl2 solution, in a completely randomized design with 4 treatments: control (without Hg2+) and treatments with 5, 24 and 36 mg Hg2+ kg-1 of soil and 5 replicates / treatment. The quantification of total Hg in plant and soil samples was performed by atomic absorption spectrometry. Kenaf grown in contaminated pots did not show visual symptoms of toxicity. Plant height did not differ among treatments, but the dry shoot phytomass was 21.65% higher in control than the average of treatments with Hg. Treatment with 24 mg kg-1 showed dry root phytomass greater than control and the others. In general, oxisol was responsible for retaining greater amount of Hg than plants. Hg accumulated in greater proportion in roots than in shoots. In pots that received 36 mg kg-1, plants accumulated average of 2.57 mg kg-1 of Hg / pot, differing from the other treatments and the Hg transfer factor (TF) in plants was also calculated as the ratio of the concentration in shoots and in roots. The values were as follows: 3.11 for T1, 1.26 for T2, 0.05 for T3 and 0.02 for T4. Treatments showed no difference between T3 and T4 and TF decreased with increasing Hg dose. It could be concluded that Hg was more adsorbed by oxisol than by plants. Plants showed resistance to different soil Hg concentrations and can be considered as potential Hg2+ stabilizer

scholarly journals Soil penetration resistance in a rhodic eutrudox affected by machinery traffic and soil water content

2013 ◽  
Vol 33 (4) ◽  
pp. 748-757 ◽  
Author(s):  
Moacir T. de Moraes ◽  
Henrique Debiasi ◽  
Julio C. Franchini ◽  
Vanderlei R. da Silva
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Soil Water Content ◽  
Soil Compaction ◽  
Crop Yields ◽  
Penetration Resistance ◽  
Soil Bulk Density ◽  
Front Axle ◽  
Undisturbed Soil ◽  
Soil Penetration Resistance

Soil compaction caused by machinery traffic reduces crop yields. This study aimed to evaluate the effects of intensive traffic, and the soil water content, on the soil penetration resistance (PR) of a Rhodic Eutrudox (Distroferric Red Latosol, Brazilian Classification), managed under no-tillage (NT). The experiment consisted of six treatments: NT with recent chiseling, NT without additional compaction, and NT with additional compaction by 4, 8, 10 and 20 passes of a harvester with a weight of 100 kN (70 kN on the front axle). Undisturbed soil samples were collected at 5.5-10.5 cm and 13.5-18.5 cm depth to quantify the soil bulk density (BD). The PR was assessed in four periods, using an impact penetrometer, inserted in the soil to a depth of 46 cm. The effect of traffic intensities on the PR was small when this variable was assessed with the soil in the plastic consistency. Differences in PR among treatments increased as the soil water content decreased. The increase in the values of PR and BD was higher in the first passes, but the increase in the number of traffics resulted in deeper soil compaction. The machinery traffic effects on PR are better characterized in the friable soil consistency.

scholarly journals Soil compaction and fertilization in soybean productivity

2004 ◽  
Vol 61 (6) ◽  
pp. 626-631 ◽  
Author(s):  
Amauri Nelson Beutler ◽  
José Frederico Centurion
Keyword(s):  
Glycine Max ◽  
Soil Compaction ◽  
Dry Matter ◽  
Penetration Resistance ◽  
Variable Number ◽  
Experimental Unit ◽  
Seed Productivity ◽  
Soil Fertilization ◽  
Randomized Design ◽  
Completely Randomized Design

Soil compaction and fertilization affect soybean development. This study evaluated the effects of soil compaction and fertilization on soybean (Glycine max cv. Embrapa 48) productivity in a Typic Haplustox under field conditions in Jaboticabal, SP, Brazil. A completely randomized design with a 5 x 2 factorial layout (compaction vs. fertilization), with four replications in each treatment, was employed. Each experimental unit (replicate) consisted of a 3.6 m² useful area. After the soil was prepared by cultivation, an 11 Mg tractor passed over it a variable number of times to create five levels of compaction. Treatments were: T0= no compaction, T1= one tractor pass, T2= two, T4= four, and T6= six passes, and no fertilizer and fertilizer to give soybean yields of 2.5 to 2.9 Mg ha-1. Soil was sampled at depths of 0.02-0.05, 0.07-0.10, and 0.15-0.18 m to determine macro and microporosity, penetration resistance (PR), and bulk density (Db). After 120 days growing under these conditions, the plants were analyzed in terms of development (plant height, number of pods, shoot dry matter per plant and weight of 100 seeds) and seed productivity per hectare. Soil compaction decreased soybean development and productivity, but this effect was decreased by soil fertilization, showing that such fertilization increased soybean tolerance to soil compaction.

scholarly journals Isolation and Characterization of Yeasts from Rumen Fluids for Potential Use as Additives in Ruminant Feeding

2021 ◽  
Vol 8 (3) ◽  
pp. 52
Author(s):  
Chanon Suntara ◽  
Anusorn Cherdthong ◽  
Metha Wanapat ◽  
Suthipong Uriyapongson ◽  
Vichai Leelavatcharamas ◽  
...  
Keyword(s):  
Incubation Time ◽  
Cellulase Activity ◽  
The Other ◽  
Pichia Kudriavzevii ◽  
Factor B ◽  
Yeast Strains ◽  
Randomized Design ◽  
Holstein Friesian ◽  
The Media ◽  
Completely Randomized Design

Saccharomyces cerevisiae is a yeast strain often used to improve the feed quality of ruminants. However, S. cerevisiae has limited capacity to provide biomass when inoculated with carbon sources and a low ability to produce cellulase enzymes. Here, we hypothesized that yeast in the rumen produces a large amount of biomass and could release cellulase enzymes to break down fiber content. Therefore, the aim of this study was to screen, isolate and identify yeast from the rumen fluids of Holstein Friesian steers and measure the efficiency of biomass production and cellulase activity. A fermentation medium containing sugarcane molasses as a carbon source and urea as a nitrogen source was optimized. Two fistulated–crossbred Holstein Friesian steers averaging 350 ± 20 kg body weight were used to screen and isolate the ruminal yeast. Two experiments were designed: First, a 12 × 3 × 3 factorial was used in a completely randomized design to determine biomass and carboxymethyl cellulase activity. Factor A was the isolated yeast and S. cerevisiae. Factor B was sugarcane molasses (M) concentration. Factor C was urea (U) concentration. In the second experiment, potential yeasts were selected, identified, and analyzed for 7 × 4 factorial use in a completely randomized design. Factor A was the incubation times. Factor B was the isolated yeast strains, including codes H-Khon Kaen University (KKU) 20 (as P. kudriavzevii-KKU20), I-KKU20 (C. tropicalis-KKU20), and C-KKU20 (as Galactomyces sp.-KKU20). Isolation was imposed under aerobic conditions, resulting in a total of 11 different colonies. Two appearances of colonies including asymmetric colonies of isolated yeast (indicated as A, B, C, E, and J) and ovoid colonies (coded as D, F, G, H, I, and K) were noted. Isolated yeast from the rumen capable of providing a high amount of biomass when inoculant consisted of the molasses 15% + urea 3% (M15 + U3), molasses 25% + urea 1% (M25 + U1), molasses 25% + urea 3% (M25 + U3), and molasses 25% + urea 5% (M25 + U5) when compared to the other media solution (p < 0.01). In addition, 11 isolated biomass-producing yeasts were found in the media solution of M25 + U1. There were 4 isolates cellulase producing yeasts discovered in the media solution of M25 + U1 and M25 + U5 whereas molasses 5% + urea 1% (M5 + U1), molasses 5% + urea 3% (M5 + U3), molasses 5% + urea 5% (M5 + U5), molasses 15% + urea 1% (M15 + U1), molasses 15% + urea 3% (M5 + U3), and M25 + U3 were found with 2, 3, 1, 2, 1, and 2 isolates, respectively. Ruminal yeast strains H-KKU20, I-KKU20, and C-KKU20 were selected for their ability to produce biomass. Identification of isolates H-KKU20 and I-KKU20 revealed that those isolates belonged to Pichia kudriavzevii-KKU20 and Candida tropicalis-KKU20 while C-KKU20 was identified as Galactomyces sp.-KKU20. Two strains provided maximum cell growth: P. kudriavzevii-KKU20 (9.78 and 10.02 Log cell/mL) and C. tropicalis-KKU20 (9.53 and 9.6 Log cells/mL) at 60 and 72 h of incubation time, respectively. The highest ethanol production was observed in S. cerevisiae at 76.4, 77.8, 78.5, and 78.6 g/L at 36, 48, 60, and 72 h of incubation time, respectively (p < 0.01). The P. kudriavzevii-KKU20 yielded the least reducing sugar at about 30.6 and 29.8 g/L at 60 and 72 h of incubation time, respectively. The screening and isolation of yeasts from rumen fluids resulted in 11 different yeasts being obtained. The potential yeasts discovered in the rumen fluid of cattle were Pichia kudriavzevii-KKU20, Candida tropicalis-KKU20, and Galactomyces sp.-KKU20. P. kudriavzevii-KKU20 had higher results than the other yeasts in terms of biomass production, cellulase enzyme activity, and cell number.

The influence of forest site on rate and extent of soil compaction and profile disturbance of skid trails during ground-based harvesting

2000 ◽  
Vol 30 (8) ◽  
pp. 1196-1205 ◽  
Author(s):  
J R Williamson ◽  
W A Neilsen
Keyword(s):  
Root Growth ◽  
Soil Compaction ◽  
Forest Type ◽  
Soil Bulk Density ◽  
Parent Material ◽  
Forest Site ◽  
Undisturbed Soil ◽  
Soil Parent Material ◽  
Wet Forests

Soil compaction has been considered a principal form of damage associated with logging, restricting root growth and reducing productivity. The rate and extent of soil compaction on skid trails was measured at six field locations covering a range of dry and wet forests. Data was collected for up to 21 passes of a laden logging machine. A similar extent of compaction, averaging 0.17 g·cm-3 increase in total soil bulk density (BD), was recorded for all field sites despite substantial site and soil differences. On average, 62% of the compaction in the top 10 cm of the soil occurred after only one pass of a laden logging machine. The environment under which soils had formed played a major role in determining the BD of the undisturbed soil. Compaction was strongly related to the original BD, forest type, and soil parent material. Soil strengths obtained in the field fell below levels found to restrict root growth. However, reduction in macropores, and the effect of that on aeration and drainage could reduce tree growth. On the wettest soils logged, machine forces displaced topsoils rather than causing compaction in situ. Recommended logging methods and implications for the development of sustainability indices are discussed.

scholarly journals Deep subsoiling of a subsurface-compacted typical hapludult under citrus orchard

2013 ◽  
Vol 37 (4) ◽  
pp. 911-919 ◽  
Author(s):  
João Carlos Medeiros ◽  
Getulio Coutinho Figueiredo ◽  
Álvaro Luiz Mafra ◽  
Jaqueline Dalla Rosa ◽  
Sung Won Yoon
Keyword(s):  
Hydraulic Conductivity ◽  
Management Practices ◽  
Soil Management ◽  
Penetration Resistance ◽  
Soil Bulk Density ◽  
Soil Samples ◽  
Fruit Yield ◽  
Root Depth ◽  
Citrus Orchard ◽  
Unsaturated Hydraulic Conductivity

Soil management practices which increase the root depth penetration of citrus are important to the longevity and yield maintenance of this plant, especially in regions where long periods of drought are common, even in soil conventionally subsoiled to a depth of 30-40 cm, when the orchard was first established. The objective of this study was to evaluate the efficiency of subsoiling on the physical and hydric properties of a Typical Hapludult and fruit yield in a 14-year-old citrus orchard located in Piracicaba, SP. The treatments consisted of: no-subsoiling (with no tilling of the soil after the orchard was planted); subsoiling on one side of the plant lines (SUB. 1); and subsoiling on both sides of the plant lines (SUB. 2). The subsoiling treatments were carried out 1.5 m from the plant lines and to a depth of 0.8 m. Soil samples were taken 120 days after this operation, at four depths, in order to determine physical and hydric properties. Fruit yield was evaluated 150 days after subsoiling. Subsoiling between the plant lines of an old established citrus orchard alters the physical and hydric properties of the soil, which is reflected in increased soil macroporosity and unsaturated hydraulic conductivity, and reduced soil bulk density, critical degree-of-compactness and penetration resistance. The improvements in the physical and hydric properties of the soil were related to an increase in fruit number and orchard yield.

scholarly journals Infestation of froghopper nymphs changes the amounts of total phenolics in sugarcane

2005 ◽  
Vol 62 (6) ◽  
pp. 543-546 ◽  
Author(s):  
Rafael José Navas da Silva ◽  
Eduardo Rossini Guimarães ◽  
José Francisco Garcia ◽  
Paulo Sérgio Machado Botelho ◽  
Maria Inês Tiraboschi Ferro ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Low Temperature ◽  
Temperature Variation ◽  
Total Phenolics ◽  
The Other ◽  
Plant Phenolics ◽  
High Moisture ◽  
Randomized Design ◽  
Leaf Tissues ◽  
Completely Randomized Design

The increased rate of sugarcane harvest without previous burn has provided a very favorable environment to the froghopper Mahanarva fimbriolata (Stal, 1854), with high moisture and low temperature variation. Few works have studied the response of sugarcane to this pest, so little is known about resistant cultivars. Plant phenolics are widely studied compounds because of their known antiherbivore effect. This research aims to determine if the attack of M. fimbriolata nymphs stimulates the accumulation of total phenolics in sugarcane. The experiment was carried out in greenhouse and arranged in completely randomized design, in a 3 X 2 X 4 factorial with three replications. Second instar nymphs of M. fimbriolata were infested at the following rates: control, 2-4 and 4-8 nymphs per pot (first-second infestations, respectively). Pots were covered with nylon net and monitored daily to isolate the effect of leaf sucking adults. Leaf and root samples were collected and kept frozen in liquid nitrogen until analyses. Infested plants showed higher levels of phenolics in both root and leaf tissues. In roots, the cultivar SP80-1816 accumulated more phenolic compounds in response to the infestation of M. fimbriolata. On the other hand, higher levels were found in leaves and roots of control plants of SP86-42, which might be an indication of a non-preference mechanism. The increase of total phenolics in sugarcane infested with root-sucking froghopper nymphs does not seem to be useful to detect the resistance to this pest.

scholarly journals Analisis Efektifitas Tepung Jamur sebagai Larvasida Aedes aegypti

2012 ◽  
Vol 14 (1) ◽  
pp. 126
Author(s):  
Yekki Yasmin ◽  
Lenni Fitri ◽  
Betty Mauliya Bustam
Keyword(s):  
Aedes Aegypti ◽  
Beauveria Bassiana ◽  
Storage Time ◽  
Natural Sciences ◽  
The Other ◽  
Biology Department ◽  
Randomized Design ◽  
Two Factors ◽  
Result Show ◽  
Completely Randomized Design

This research is about effectivity analysis of two kinds of fungi i.e. Beauveria bassiana and Metharrizium anisopliae as Aedes aegyptilarvacide, it has been conducted at laboratories Zoology in Biology Department, Mathematics and Natural Sciences Faculty, Syiah KualaUniversity. Aims of this research were estimating maximum time storage of fungi powder as effective larvacide and the number of bacteriacolonies were found in water used for experiment. This research was used Completely Randomized Design (CRD). The experiments consistof two factors i.e kind and saving time of fungi. The result show that the longer the storage time of Beauveria bassiana the more ineffectiveit was as larvacide and the least fungi colonies were found. Metharrizium anisopliae on the other hand, the longer it was kept, the moreeffective it was as larvacide and the more fungi colonies were found.

scholarly journals Leaching of Picloram in ultisol under different rainfall volumes

2011 ◽  
Vol 29 (spe) ◽  
pp. 1129-1136 ◽  
Author(s):  
E.C Assis ◽  
A.A Silva ◽  
L D'Antonino ◽  
M.E.L.R Queiroz ◽  
L.C Barbosa
Keyword(s):  
Liquid Chromatography ◽  
High Performance ◽  
Soil Samples ◽  
Soil Sampling ◽  
Horizontal Position ◽  
Leaching Potential ◽  
Excess Water ◽  
Randomized Design ◽  
Completely Randomized Design ◽  
Plot Design

The present study aimed to evaluate the leaching potential of Picloram in Ultisol columns under different rainfall amounts. For such, 30 treatments were evaluated (one soil associated with three levels of rainfall and ten depths).The experiments were arranged in a split-plot design, in a completely randomized design, with four replications. PVC columns of 10 cm in diameter and 50 cm in length were filled with these soils, moistened, and placed upright for 48 hours to drain the excess water. The herbicide was applied and rainfall simulations were carried out at specified intensities, according to the treatments, to force Picloram leaching. After 72 hours, all the columns were arranged in a horizontal position and opened lengthwise. Then, soil sampling was carried out every 5 cm of depth for subsequent herbicide extraction and quantification and analysis by high performance liquid chromatography. The remaining soil samples were placed in plastic pots, and, at the respective depths, the indicator species Cucumis sativus was sown. Twenty-one days after the emergence (DAE) of the indicator plants, evaluations were conducted to verify the symptoms of toxicity caused by Picloram in the plants. It was concluded that Picloram leaching is directly dependent on the volume of rain applied. The herbicide reached the deepest regions in the soil with the highest intensity of rain. The results obtained by bioassay were in agreement with those found by liquid chromatography.

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