scholarly journals Studies on the Chilling Injury in Wheat Plants : IX. Field investigations on injury caused by low temperature before and after the flowering stage

1972 ◽  
Vol 41 (3) ◽  
pp. 310-314
Author(s):  
Masayuki TODA
Keyword(s):  
Low Temperature ◽  
Chilling Injury ◽  
Flowering Stage ◽  
Field Investigations ◽  
Before And After

The decline and recovery of photosynthesis of ponderosa pine seedlings subjected to low, but above freezing temperatures

1972 ◽  
Vol 50 (9) ◽  
pp. 1965-1970 ◽  
Author(s):  
R. P. Pharis ◽  
H. Hellmers ◽  
E. Schuurmans
Keyword(s):  
Low Temperature ◽  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Dark Respiration ◽  
Chilling Injury ◽  
Freezing Temperature ◽  
Pine Seedlings ◽  
Before And After ◽  
Order Of Magnitude ◽  
Respiratory Apparatus

The daily course of photosynthesis (Ps) was determined for ponderosa pine (Pinus ponderosa Laws.) seedlings before and after their transfer from 23° to 11° or 3 °C and vice versa. Apparent Ps at 11 °C was greater than at 23 °C for up to 17 days after transfer. The increase was of the same order of magnitude as the decrease noted in dark respiration (Rs). Apparent Ps at 3 °C was little affected for the first 3 days after transfer, but declined to about 70% of pretreatment rate by day 10. If dark Rs at 3 °C is taken into account, actual Ps declined to about 50% of pretreatment rate by day 10. After this, the decline in Ps, with time, proceeds slowly. Recovery of Ps after transfer from the lower temperatures to 23 °C was rapid only if the length of time at the low temperature did not exceed 1 day. Return of apparent Ps to pretreatment rates was accomplished by day 7 for plants subjected to 17 days of 11 °C. Recovery of apparent Ps for plants subjected to 4 or more days of 3 °C reached 80% by day 7, and 90% by day 23. Dark Rs of plants brought from 3° to 23 °C was increased appreciably at first, this increase being of the same order of magnitude as the decrease in apparent Ps. Dark Rs then decreased with time at 23 °C, this decrease being correlated with an increase in apparent Ps. It is concluded that the initial chilling "injury," if any, occasioned by very low, but above freezing temperature, does not involve the physical or metabolic apparatus of Ps, but rather is associated with the respiratory apparatus as evidenced by increased rates of dark Rs during recovery at higher temperatures.

Fresh-cut Mango Fruit Slices

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 457b-457 ◽  
Author(s):  
Arunya Limbanyen ◽  
Jeffrey K. Brecht ◽  
Steven A. Sargent ◽  
Jerry A. Bartz
Keyword(s):  
Chilling Injury ◽  
Flesh Color ◽  
Mango Fruit ◽  
Heat Treated ◽  
Before And After ◽  
Yellow Flesh ◽  
Postharvest Life ◽  
Fresh Cut ◽  
Flesh Browning ◽  
Aseptic Conditions

Preparation and handling procedures for fresh-cut mango slices were developed using `Tommy Atkins', `Haden', and `Palmer' mangoes. Fruit with yellow flesh color (no green color remaining) were optimum maturity for fresh-cut in terms of maintenance of acceptable appearance, texture, and taste; riper fruit developed flesh breakdown and more browning. Postharvest life of fresh-cut mango at 5 °C was 8 to 10 d with no evidence of chilling injury and was limited by flesh browning and loss of firmness. Respiration rates ranged from 32 to 40 mg CO2/kg per hr and ethylene production was typically ≤0.1 μl·kg–1·hr–1. The SSC changed little during storage, while pH varied from 3.5 to 4.8 and TA typically declined by 30% to 40%. Peeling to a depth of at least 2 mm and trimming flesh near the stem scar was necessary to minimize browning. Imported fruit that had been heat-treated for insect quarantine showed more severe browning than Florida fruit that had not been heat-treated. Preparation in aseptic conditions and dipping fruit in a 100 ppm NaOCl solution at pH 7 before and after peeling protected against decay during storage but dipping in chlorine after slicing without removal of excess liquid resulted in flesh translucency and breakdown. Dipping in 1% CaCl2 solution had no effect on flesh firmness (Instron) or browning. Storage in an unvented plastic clamshell container, which developed an atmosphere of 2.25% CO2 plus 19% O2, did not improve shelf life, but a MA of 10% CO2 plus 10% O2 was subjectively judged to slow browning and softening and resulted in no off flavor compared to air storage.

scholarly journals Effects of equal channel angular pressing and heat treatments on the microstructures and mechanical properties of selective laser melted and cast AlSi10Mg alloys

2021 ◽  
Vol 21 (3) ◽  
Author(s):  
Przemysław Snopiński ◽  
Mariusz Król ◽  
Marek Pagáč ◽  
Jana Petrů ◽  
Jiří Hajnyš ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Low Temperature ◽  
Equal Channel Angular Pressing ◽  
Heat Treatments ◽  
Electron Backscattered Diffraction ◽  
Angular Pressing ◽  
Low Temperature Annealing ◽  
Transmission Electron ◽  
Before And After ◽  
The Impact

AbstractThis study investigated the impact of the equal channel angular pressing (ECAP) combined with heat treatments on the microstructure and mechanical properties of AlSi10Mg alloys fabricated via selective laser melting (SLM) and gravity casting. Special attention was directed towards determining the effect of post-fabrication heat treatments on the microstructural evolution of AlSi10Mg alloy fabricated using two different routes. Three initial alloy conditions were considered prior to ECAP deformation: (1) as-cast in solution treated (T4) condition, (2) SLM in T4 condition, (3) SLM subjected to low-temperature annealing. Light microscopy, transmission electron microscopy, X-ray diffraction line broadening analysis, and electron backscattered diffraction analysis were used to characterize the microstructures before and after ECAP. The results indicated that SLM followed by low-temperature annealing led to superior mechanical properties, relative to the two other conditions. Microscopic analyses revealed that the partial-cellular structure contributed to strong work hardening. This behavior enhanced the material’s strength because of the enhanced accumulation of geometrically necessary dislocations during ECAP deformation.

Changes in ACC and conjugated ACC levels following controlled atmosphere storage of nectarine

2005 ◽  
Vol 45 (12) ◽  
pp. 1635 ◽  
Author(s):  
A. Uthairatanakij ◽  
P. Penchaiya ◽  
B. McGlasson ◽  
P. Holford
Keyword(s):  
Low Temperature ◽  
Cold Storage ◽  
Low Temperatures ◽  
Prunus Persica ◽  
Chilling Injury ◽  
Controlled Atmosphere ◽  
Controlled Atmosphere Storage ◽  
Gaseous Composition ◽  
Storage Atmosphere ◽  
Atmosphere Storage

Low temperature disorders of nectarines are thought to be expressions of chilling injury. Chilling injury is a form of stress usually associated with increased synthesis of ethylene and its immediate precursor, aminocyclopropane-1-carboxylic acid (ACC). However, other mechanisms for the development of chilling injury have been proposed. To help determine the nature of the processes leading to chilling injury in nectarines (Prunus persica) and how the gaseous composition of the storage atmosphere effects the development of low temperature disorders, levels of ACC and conjugated ACC were measured in fruit of the cv. Arctic Snow. These compounds were measured in fruit ripened at 20°C immediately after harvest, in fruit on removal from cold storage and in fruit ripened at 20°C following cold storage. During storage, fruit were kept at 0°C in the 4 following atmospheres: air; air + 15% CO2; air + 15 µL/L ethylene; and air + 15% CO2 + 15 µL/L ethylene. Concentrations of ACC remained low in all treatments and no significant changes in ACC levels due to added ethylene or CO2 were observed. Concentrations of conjugated ACC were about 10-times that of ACC and again were not influenced by the composition of the storage atmosphere. No significant changes in either ACC or conjugated ACC were observed until after flesh bleeding, the major symptoms of low temperature disorder expressed in these fruit, had begun to appear. It was concluded that disorders in nectarines stored at low temperatures are not a stress response involving a disruption of ethylene metabolism but may be associated with differential changes in the metabolism of enzymes associated with normal ripening.

Environmental Influence on the Tolerance of Corn to Atrazine

Weed Science ◽  
1970 ◽  
Vol 18 (4) ◽  
pp. 509-514 ◽  
Author(s):  
Lafayette Thompson ◽  
F. W. Slife ◽  
H. S. Butler
Keyword(s):  
Zea Mays ◽  
High Temperature ◽  
Low Temperature ◽  
Light Intensity ◽  
Environmental Influence ◽  
High Light Intensity ◽  
High Light ◽  
Growth Chamber ◽  
Peptide Conjugates ◽  
Before And After

Corn(Zea maysL.) in the two to three-leaf stage grown 18 to 21 days in a growth chamber under cold, wet conditions was injured by postemergence application of 2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine (atrazine) plus emulsifiable phytobland oil. Injury was most severe when these plants were kept under cold, wet conditions for 48 hr after the herbicidal spray was applied, followed by exposure to high light intensity and high temperature. Under these growth chamber conditions, approximately 50% of the atrazine-treated plants died. Since wet foliage before and after application increased foliar penetration and low temperature decreased the rate of detoxication to peptide conjugates, atrazine accumulated under cold, wet conditions. This accumulation of foliarly-absorbed atrazine and the “weakened” conditions of the plants grown under the stress conditions is believed to be responsible for the injury to corn. Hydroxylation and the dihydroxybenzoxazin-3-one content in the roots were reduced at low temperature, but it is unlikely that this contributed to the death of the corn.

Investigation of the properties of knitted woolen fabrics treated with oxygen low-temperature plasma for sportswear applications

2021 ◽  
pp. 004051752110306
Author(s):  
Honglian Cong ◽  
Boyu Zhao ◽  
Hao Han ◽  
Xuliang Yu
Keyword(s):  
Low Temperature ◽  
Plasma Treatment ◽  
Moisture Absorption ◽  
Mapping Method ◽  
Function Evaluation ◽  
Low Temperature Plasma ◽  
Temperature Plasma ◽  
Wool Fibers ◽  
Before And After ◽  
Concentration Mapping

Nine groups of knitted woolen fabrics for sportswear with different technical characteristics were treated with oxygen low-temperature plasma, and the changes in the surface morphology and chemical composition of wool fibers before and after plasma treatment, as well as the changes in the applicability indexes of knitted woolen fabrics, were studied. Finally, the comfort performance of the fabrics was evaluated by combining the concentration mapping method and the function evaluation value method. The analysis found that the surface scales of wool fibers were seriously etched after oxygen low-temperature plasma treatment, and the anti-felting, bursting strength and moisture absorption of the knitted woolen fabrics were improved. At the same time, the quick-drying index of the fabric has also been improved to a certain extent. This research provides a basis for the development of knitted woolen fabric for sportswear with excellent performance.

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