MICROORGANISMS IN THE ROOT ZONE IN RELATION TO TEMPERATURE

1963 ◽  
Vol 9 (2) ◽  
pp. 227-236 ◽  
Author(s):  
J. W. Rouatt ◽  
E. A. Peterson ◽  
H. Katznelson ◽  
V. E. Henderson
Keyword(s):  
High Temperature ◽  
Root Zone ◽  
Optimal Growth ◽  
Bacterial Isolates ◽  
Wheat Roots ◽  
Increased Temperature ◽  
As Species ◽  
Higher Temperature ◽  
Soybean Roots ◽  
Generic Analysis

A study was made of the numbers and kinds of microorganisms in the root zone of wheat and soybeans grown in the greenhouse at three ranges of temperature: 55–60°, 70–75°, and 85–90 °F. Numbers of bacteria in the rhizosphere and rhizoplane of wheat decreased as the temperature increased, whereas numbers in the root-free soil and on soybean roots increased with increased temperature. The same relationships held for methylene blue reducing, glucose-fermenting, and ammonifying bacteria and those requiring amino acids for optimal growth. Generic analysis of bacterial isolates showed that the percentage of Gram-negative rod-forming organisms increased with a rise in temperature in root-free soil and on soybean roots but decreased on wheat roots. On the other hand, the incidence of Gram-positive and pleomorphic organisms decreased in soil and on soybean roots with higher temperature and increased on wheat roots.Fungal isolations from washed root segments showed a greater incidence of Mucor, Rhizopus, Rhizoctonia, and Gliocladium on soybeans at the high temperature whereas species of Fusarium and Cylindrocarpon were more prevalent at the low temperature. With wheat the most striking feature was the predominance of non-sporing dark species at the high temperature and of non-sporing hyaline types at the low temperature.The number of soil nematodes decreased in the rhizospheres of both plants with increased temperature, the effect being more pronounced with soybeans. With this crop all except one of the genera recognized decreased in number, whereas with wheat, the incidence of certain nematodes such as species of Helicotylenchus, Boleodorus, and Aphelenchoides did not change with temperature.The results suggest that temperature exerts a direct effect on the microorganisms in the root zone and an indirect effect by influencing plant growth.

METABOLIC ACTIVITY AND PHOSPHATE-DISSOLVING CAPABILITY OF BACTERIAL ISOLATES FROM WHEAT ROOTS, RHIZOSPHERE, AND NON-RHIZOSPHERE SOIL

1959 ◽  
Vol 5 (1) ◽  
pp. 79-85 ◽  
Author(s):  
H. Katznelson ◽  
B. Bose
Keyword(s):  
Metabolic Activity ◽  
Rhizosphere Soil ◽  
Root Zone ◽  
Optimal Growth ◽  
Bacterial Isolates ◽  
Wheat Roots ◽  
Soil Extracts ◽  
Large Numbers ◽  
Insoluble Phosphorus ◽  
Phosphate Solubilizing

Bacterial isolates from the roots of wheat (rhizoplane) were more active in oxidizing glucose and alanine than cultures isolated from rhizosphere and non-rhizosphcre soils. In general, metabolic activity was greater with alanine than with glucose. Over one third of the cultures tested were capable of dissolving insoluble phosphorus in the form of CaHPO4 but the roots did not appear to exert a selective effect on these forms. However, the phosphate-solubilizing organisms from the rhizoplane were also the most active in oxidizing glucose and alanine. Those from the rhizosphere soil were intermediate in this respect. By far the majority of these phosphate-dissolving bacteria were in the nutritional group requiring unknown substances in yeast and soil extracts for optimal growth. It was suggested that although these bacteria were not preferentially stimulated in the root zone, their large numbers and their greater metabolic activity may contribute significantly to the phosphate economy of the plant.

Effectiveness of complex inoculation of spring wheat with N[2] -fi xing bacteria Azospirillum brasilense and mold-antagonist Chaetomium cochliodes

2014 ◽  
Vol 1 (3) ◽  
pp. 57-61
Author(s):  
E. Kopylov
Keyword(s):  
Spring Wheat ◽  
Root Zone ◽  
Wheat Root ◽  
Root Surface ◽  
Atmospheric Nitrogen ◽  
Rhizospheric Soil ◽  
Chain Reaction ◽  
Wheat Roots ◽  
Chlorophyll A And B ◽  
Polymerase Chain

Aim. To study the specifi cities of complex inoculation of spring wheat roots with the bacteria of Azospirillum genus and Chaetomium cochliodes Palliser 3250, and the isolation of bacteria of Azospirillum genus, capable of fi xing atmospheric nitrogen, from the rhizospheric soil, washed-off roots and histoshere. Materials and meth- ods. The phenotypic features of the selected bacteria were identifi ed according to Bergi key. The molecular the polymerase chain reaction and genetic analysis was used for the identifi cation the bacteria. Results. It has been demonstrated that during the introduction into the root system of spring wheat the strain of A. brasilensе 102 actively colonizes rhizospheric soil, root surface and is capable of penetrating into the inner plant tissues. Conclusions. The soil ascomucete of C. cochliodes 3250 promotes better settling down of Azospirillum cells in spring wheat root zone, especially in plant histosphere which induces the increase in the content of chlorophyll a and b in the leaves and yield of the crop.

scholarly journals Improved high-temperature damping performance of nitrile-butadiene rubber/phenolic resin composites by introducing different hindered amine molecules

e-Polymers ◽  
2020 ◽  
Vol 20 (1) ◽  
pp. 482-490
Author(s):  
Meng Song ◽  
Xiulin Yue ◽  
Xiujuan Wang ◽  
Mengjie Huang ◽  
Mingxing Ma ◽  
...  
Keyword(s):  
High Temperature ◽  
Phenolic Resin ◽  
Thermomechanical Analysis ◽  
Butadiene Rubber ◽  
Scanning Calorimetry ◽  
Nitrile Butadiene Rubber ◽  
Theoretical Support ◽  
Higher Temperature ◽  
Damping Materials ◽  
Hybrid Damping

AbstractBy introducing hindered amine GW-622 or GW-944 into nitrile-butadiene rubber/phenolic resin (NBR/PR, abbreviated as NBPR) matrix, we have prepared different hindered amine/NBR/PR ternary hybrid damping materials with high-temperature damping performance, respectively. Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM), differential scanning calorimetry (DSC), and dynamic thermomechanical analysis (DMA) were used to research the microstructure, compatibility, and damping properties of the hindered amine/NBPR composites. FTIR results indicate that hydrogen bonds are formed between the hindered amine and the NBPR matrix. Both DSC and SEM results show that hindered amine has partial compatibility with the NBPR matrix. DMA results show that two loss peaks appear in the hindered amine/NBPR composite. Thereby, the composites show better damping performance at a higher temperature, and the temperature domain of high-temperature damping becomes wider with the increase in the addition of hindered amine. This study provides a theoretical support for the preparation of high-temperature damping materials.

scholarly journals Temporal Patterns of Flowering and Pod Set of Determinate Soybean in Response to High Temperature

Agronomy ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 414 ◽  
Author(s):  
Yean-Uk Kim ◽  
Doug-Hwan Choi ◽  
Ho-Young Ban ◽  
Beom-Seok Seo ◽  
Junhwan Kim ◽  
...  
Keyword(s):  
High Temperature ◽  
High Temperatures ◽  
Temporal Distribution ◽  
Temporal Patterns ◽  
Bimodal Distribution ◽  
Flowering Duration ◽  
Sowing Dates ◽  
Glycine Max L ◽  
Higher Temperature ◽  
Pod Number

Global warming is expected to affect yield-determining factors of soybean (Glycine max (L.) Merr.), including the number of flowers and pods. However, little is known about the effects of high temperature on the temporal patterns of flowering and pod set. Experiments in the temperature-controlled greenhouses were conducted to examine the temporal pattern of flowering in determinate soybean cultivar “Sinpaldalkong” and to assess the effects of high temperature on the flower number, pod-set ratio, and pod number of the early- and late-opened-flowers and their contributions to overall pod number. The experiment comprised five sowing dates in 2013–2015 and four temperature treatments, namely ambient temperature (AT), AT + 1.5 °C, AT + 3.0 °C, and AT + 5.0 °C. Flowering duration (i.e., days between the first flowering and the last flowering) was extended by higher temperature and earlier sowing. The temporal distribution of flowering showed a bimodal distribution except for the experiment with the shortest flowering duration, i.e., second sowing in 2014. More flowers were produced in the late flowering period at high temperatures; however, most of these late-opened-flowers failed to reproduce, regardless of temperature conditions, resulting in a negligible contribution to the overall pod number. For the early-opened-flowers, the number of flowers was not significantly affected by temperature, while the pod-set ratio and pod number decreased with high temperatures resulting in a decrease in the overall pod number at temperatures above 29.4 °C.

Preparation of Butadiene

1928 ◽  
Vol 1 (2) ◽  
pp. 208-210
Author(s):  
Stanley Francis Birch
Keyword(s):  
Heat Treatment ◽  
High Temperature ◽  
Liquid Phase ◽  
High Temperatures ◽  
Vapor Phase ◽  
Complex Mixture ◽  
Higher Temperature ◽  
Oil Gas

Abstract OF THE numerous methods available for the preparation of butadiene in the laboratory, those described by Thiele and by Ostromuislenskii are probably the most convenient. Both, however, suffer from the disadvantages which usually characterize operations at comparatively high temperatures; the exact conditions are difficult to find, the process is long and tedious, and finally involves the separation of the required material from a complex mixture. It has long been known that butadiene occurs in the various products obtained when oils are heated to a high temperature. Caventou first isolated butadiene in the form of its tetrabromide from illuminating gas, and Armstrong and Miller definitely established the presence of butadiene in the liquid obtained by compressing oil gas. The work of numerous later investigators has confirmed their results and has shown that the more drastic the heat treatment to which the oil is submitted the greater is the tendency for butadiene to be formed. For this reason vapor-phase cracking of petroleum, which is carried out at a much higher temperature than liquid-phase cracking, yields products specially rich in butadiene.

Rhythmic patterns of nutrient acquisition by wheat roots

2002 ◽  
Vol 29 (5) ◽  
pp. 595 ◽  
Author(s):  
Sergey Shabala ◽  
Andrew Knowles
Keyword(s):  
Root Zone ◽  
Root Hairs ◽  
Rhythmic Activity ◽  
Root Apex ◽  
Root Surface ◽  
Ion Flux ◽  
Nutrient Acquisition ◽  
Wheat Roots ◽  
Non Invasive ◽  
Functional Zone

Oscillatory patterns in H+, K+, Ca2+ and Cl- uptake were observed at different regions of the root surface, including root hairs, using a non-invasive ion flux measuring technique (the MIFE™ technique). To our knowledge, this is the first report of ultradian oscillations in nutrient acquisition in the mature root zone. Oscillations of the largest magnitude were usually measured in the elongation region, 2–4 mm from the root apex. There were usually at least two oscillatory components present for each ion measured: fast, with periods of several minutes; and slow, with periods of 50–80 min. Even within the same functional zone, the periods of ion flux oscillations were significantly different, suggesting that they are driven by some internal mechanisms located in each cell rather than originating from one ‘central clock pacemaker’. There were also significant changes in the oscillatory characteristics (both periods and amplitudes) of fluxes from a single small cluster of cells over time. Analysis of phase shifts between oscillations in different ions suggested that rhythmic activity of a plasma membrane H+-pump may be central to observed rhythmic nutrient acquisition by plant roots. We discuss the possible adaptive significance of such an oscillatory strategy for root nutrient acquisition.

Effect of heat treatment and heat treatment in combination with lignosulfonate on in situ rumen degradability of canola cake crude protein, lysine, and methionine

2020 ◽  
Vol 100 (1) ◽  
pp. 165-174 ◽  
Author(s):  
Piotr Micek ◽  
Katarzyna Słota ◽  
Paweł Górka
Keyword(s):  
Heat Treatment ◽  
High Temperature ◽  
Crude Protein ◽  
Dry Matter ◽  
Increased Temperature ◽  
Heat Treated ◽  
Cold Pressed ◽  
Temperature Heating ◽  
High Temperature Heating

The aim of this study was to determine the effect of heat treatment alone or in combination with the addition of lignosulfonate (LSO3) on canola cake protein, lysine, and methionine degradation in the rumen. Cold-pressed canola cake was left untreated, heated at 90, 110, 130, or 150 °C, or processed with 5% of LSO3 (in dry matter) and then heated. Effective rumen degradability of crude protein (CP), lysine, and methionine was less for treated than untreated canola cake (P < 0.05) and decreased with increased temperature of heating, but particularly when canola cake was heated at 150 °C (quadratic, P < 0.01). In general, effective rumen degradability of CP, lysine, and methionine was less for canola cake heated at 130 °C in combination with LSO3 compared with canola cake heat treated only (quadratic × LSO3 interaction, P ≤ 0.07). Results of this study indicate that high temperature heating (130 °C or greater for 60 min) may be necessary to protect canola cake protein from degradation in the rumen, and the combination of heat treatment and LSO3 may be more effective in protecting canola cake protein, lysine, and methionine from degradation in the rumen than the use of heat treatment only.

Study of High-Temperature MEMS Pressure Sensor Based on SiC-AlN Structure

2013 ◽  
Vol 562-565 ◽  
pp. 471-476 ◽  
Author(s):  
Hao Jie Lv ◽  
Tao Geng ◽  
Guo Qing Hu
Keyword(s):  
High Temperature ◽  
Pressure Sensor ◽  
Sandwich Structure ◽  
High Sensitivity ◽  
High Accuracy ◽  
External Pressure ◽  
Harsh Environment ◽  
Capacitive Pressure Sensor ◽  
Technical Process ◽  
Higher Temperature

In the paper, a touch mode capacitive pressure sensor with double-notches structure is presented. The sensor employs a special SiC-AlN-SiC sandwich structure to achieve high-accuracy pressure measurement in hash environment such as high-temperature. The analysis to the relation of capacitance and external pressure of the sensor shows that the sensor has high sensitivity and long linear range simultaneously. In addition, the technical process of the sensor has been designed in detail in the paper. The research shows that the sensor packaged in a high-temperature ceramic AlN can withstand higher temperature. Consequently, the sensor can be applied in high-temperature and harsh environment.

scholarly journals Treatments of Magnesium Slag to Recycle Waste from Pidgeon Process

2011 ◽  
Vol 418-420 ◽  
pp. 1657-1667 ◽  
Author(s):  
Feng Lan Han ◽  
Qi Xing Yang ◽  
Lan Er Wu ◽  
Sheng Wei Guo
Keyword(s):  
Global Warming ◽  
High Temperature ◽  
Natural Resources ◽  
Building Materials ◽  
Volume Stability ◽  
Global Warming Impact ◽  
Slag Powder ◽  
Magnesium Production ◽  
Higher Temperature ◽  
Pidgeon Process

Magnesium slag powder from a local magnesium plant was treated to improve the volume stability for its application as building materials. The slag was mixed with borates, pressed into briquettes, and then sintered at high temperature. SEM studies show that at the higher temperature Ca2SiO4polymorphs were stabilized by Na and B ions in the added borates. The free MgO content in the slag was also decreased by the sintering treatment. The slag powder, after mixing with 0.4-0.6% of borates and sintered at 1200°C in 5-6 hours, has become volume stable aggregates. It is then possible to use the treated slag in constructions, saving valuable natural resources and decreasing the global warming impact from magnesium production via Pidgeon process.

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