Light Intensity: the Role Player in Cucumber Response to Cold Stress

2021 ◽  
Author(s):  
Tahereh Ashrestaghi ◽  
Sasan Aliniaeifard ◽  
Aida Shomali ◽  
Shiva Azizinia ◽  
Jahangir Abbasi Koohpalekani ◽  
...  
Keyword(s):  
Low Temperature ◽  
Light Intensity ◽  
Cold Stress ◽  
Low Temperatures ◽  
Warm Season ◽  
Water Soluble ◽  
Photon Flux ◽  
Soluble Carbohydrate ◽  
Dependent Manner ◽  
Biochemical Traits

Abstract Low temperatures are an important limitation for geographic distributions of warm-season crops like cucumber (Cucumis sativus L.). Tolerance to low temperatures varies among different plant species and genotypes when changes in normal environmental cues occur. To cope with low temperature, biochemical and biophysical events should be coordinated to form a physiological response. We examined how light intensity influences the effects of low temperature on photosynthesis machinery and some biochemical traits. We used chlorophyll fluorescence imaging and polyphasic fluorescence transient (OJIP) to analyze cold stress (4 ºC) damage to photosynthetic electron transport chain (ETC) under different Photosynthetic Photon Flux Densities (PPFDs; 0, 300 and 600 μmol m-2 s-1), in four accessions of cucumber. The results showed that, the negative effects of cold stress are PPFD-dependent. The adverse effect of cold stress on ETC was more pronounced in plants exposed to 600 μmol m-2 s-1 compared to the control and dark-exposed plants; indicated by disturbance in ETC and higher energy dissipation. Moreover, biochemical traits including H2O2 content, ascorbate peroxidase activity and electrolyte leakage, and water-soluble carbohydrate was increased under low temperature by increase in PPFD, while chlorophyll and carotenoid contents decreased under low temperature by PPFD elevation. Low temperature induced H2O2 accumulation via suppressing APX activity in a PPFD-dependent manner. In conclusion, high PPFDs exacerbate the adverse effects of low temperature on the cucumber seedlings.

scholarly journals Light Intensity: The Role Player in Cucumber Response to Cold Stress

Agronomy ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 201
Author(s):  
Tahereh Ashrostaghi ◽  
Sasan Aliniaeifard ◽  
Aida Shomali ◽  
Shiva Azizinia ◽  
Jahangir Abbasi Koohpalekani ◽  
...  
Keyword(s):  
Electron Transport ◽  
Low Temperature ◽  
Light Intensity ◽  
Cold Stress ◽  
Ascorbate Peroxidase ◽  
Peroxidase Activity ◽  
Low Temperatures ◽  
Electron Transport Chain ◽  
Biochemical Traits ◽  
Transport Chain

Low temperatures are a substantial limitation in the geographic distribution of warm-season crops such as cucumber (Cucumis sativus L.). Tolerance to low temperatures varies among different plant species and genotypes when changes in environmental cues occur. Therefore, biochemical and biophysical events should be coordinated to form a physiological response and cope with low temperatures. We examined how light intensity influences the effects of low temperature on photosynthesis and some biochemical traits. We used chlorophyll fluorescence imaging and polyphasic fluorescence transient to analyze cold stress damage by 4 °C. Photosynthetic Photon Flux Densities (PPFDs) of 0, 300, and 600 μmol m−2 s−1, in four accessions of cucumber, were investigated. The results show that the negative effects of cold stress are PPFD-dependent. The adverse effect of cold stress on the electron transport chain is more pronounced in plants exposed to 600 μmol m−2 s−1 than the control and dark-exposed plants, indicated by a disturbance in the electron transport chain and higher energy dissipation. Moreover, biochemical traits, including the H2O2 content, ascorbate peroxidase activity, electrolyte leakage, and water-soluble carbohydrate, increased under low temperature by increasing the PPFD. In contrast, chlorophyll and carotenoid contents decreased under low temperature through PPFD elevation. Low temperature induced a H2O2 accumulation via suppressing ascorbate peroxidase activity in a PPFD-dependent manner. In conclusion, high PPFDs exacerbate the adverse effects of low temperature on the cucumber seedlings.

scholarly journals Survival of Clinical and Poultry-Derived Isolates of Campylobacter jejuni at a Low Temperature (4°C)

2001 ◽  
Vol 67 (9) ◽  
pp. 4186-4191 ◽  
Author(s):  
Kam Fai Chan ◽  
Huyen Le Tran ◽  
R. Y. Kanenaka ◽  
S. Kathariou
Keyword(s):  
Low Temperature ◽  
Campylobacter Jejuni ◽  
Cold Exposure ◽  
Low Temperatures ◽  
Prolonged Exposure ◽  
Dependent Manner ◽  
Temperature Requirements ◽  
Bacterial Gastroenteritis ◽  
Different Strains ◽  
Strain Dependent

ABSTRACT Campylobacter jejuni is a leading cause of bacterial gastroenteritis in humans, and contamination of poultry has been implicated in illness. The bacteria are fastidious in terms of their temperature requirements, being unable to grow below ca. 31°C, but have been found to be physiologically active at lower temperatures and to tolerate exposure to low temperatures in a strain-dependent manner. In this study, 19 field isolates of C. jejuni (10 of clinical and 9 of poultry origin) were studied for their ability to tolerate prolonged exposure to low temperature (4°C). Although substantial variability was found among different strains, clinical isolates tended to be significantly more likely to remain viable following cold exposure than poultry-derived strains. In contrast, the relative degree of tolerance of the bacteria to freezing at −20°C and freeze-thawing was strain specific but independent of strain source (poultry versus clinical) and degree of cold (4°C) tolerance.

scholarly journals Preliminary Findings on the Correlation between Water-soluble Carbohydrate Content in Stolons and First Year Green-up of Seeded Bermudagrass Cultivars

2010 ◽  
Vol 20 (4) ◽  
pp. 758-763 ◽  
Author(s):  
Stefano Macolino ◽  
Matteo Serena ◽  
Bernd Leinauer ◽  
Umberto Ziliotto
Keyword(s):  
Cynodon Dactylon ◽  
Warm Season ◽  
Dry Weight ◽  
Water Soluble ◽  
Soluble Carbohydrate ◽  
First Year ◽  
Green Cover ◽  
Mediterranean Countries ◽  
The University ◽  
Water Soluble Carbohydrate

Warm-season grasses are not widely accepted in Mediterranean countries because they lose color during the winter months. A study was conducted at the University of Padova (Padova, Italy) to determine whether fall and spring water-soluble carbohydrate (WSC) content in stolons of seeded bermudagrass cultivars (Cynodon dactylon) influenced spring green-up in the first year of establishment. Nine bermudagrass cultivars (La Paloma, Mohawk, NuMex Sahara, Princess 77, Riviera, SR 9554, Barbados, Contessa, and Yukon) were seeded in July 2005, and dry weight and WSC content in stolons were measured in Fall 2005 and again in Spring 2006. The percentage of green cover and days needed to achieve 80% green cover (D80) were regressed against November and March values of stolon dry weight and WSC content to determine if they were good predictors of D80. ‘Yukon’ showed earliest spring green-up by end of April, and ‘Princess 77’ and ‘Riviera’ were slowest, needing 43 to 46 days more than ‘Yukon’ to reach D80. There was a significant inverse relationship between November (r2 = 0.57) and March (r2 = 0.77) WSC content in stolons and D80 for all nine bermudagrass cultivars. These results suggest that bermudagrass cultivars with high WSC in stolons recover more rapidly from dormancy during establishment than those with low WSC content.

Effects of low temperature on leaf diffusion resistance of Ulmus americana and Fraxinus pennsylvanica seedlings

1979 ◽  
Vol 57 (21) ◽  
pp. 2466-2470 ◽  
Author(s):  
T. T. Kozlowski ◽  
S. G. Pallardy
Keyword(s):  
Low Temperature ◽  
Cold Stress ◽  
Low Temperatures ◽  
Stomatal Closure ◽  
Diffusion Resistance ◽  
Fraxinus Pennsylvanica ◽  
Ulmus Americana ◽  
Stress Treatment ◽  
Exposure To Cold

Low temperatures (3–10 °C) for 1 h to 6 days increased leaf diffusion resistance (r1) of Ulmus americana and Fraxinus pennsylvanica seedlings, indicating rapid stomatal closure. The change in r1 increased as the temperature was lowered over a range of 10–3 °C. After cessation of cold-stress treatment, r1 values recovered within 1 day to prestress levels. No significant differences were found in speed of recovery of r1 in plants after exposure to cold over a range of 3– 10 °C. Stomatal closure could account thus for at least part of the decrease in photosynthesis at low temperatures.

Response of wheat plants under post-anthesis stress induced by defoliation: II. Contribution of peduncle morpho-anatomical traits and carbon reserves to grain yield

2016 ◽  
Vol 155 (3) ◽  
pp. 475-493 ◽  
Author(s):  
D. DODIG ◽  
D. RANČIĆ ◽  
B. VUCELIĆ RADOVIĆ ◽  
M. ZORIĆ ◽  
J. SAVIĆ ◽  
...  
Keyword(s):  
Storage Capacity ◽  
Field Trials ◽  
Water Soluble ◽  
Grain Weight ◽  
Soluble Carbohydrate ◽  
Biochemical Traits ◽  
Intact Control ◽  
C Storage ◽  
Exposed Part ◽  
Water Soluble Carbohydrate

SUMMARYAssimilated carbon during vegetative and early reproductive growth in wheat is temporarily stored in stem internodes and leaf sheaths (LSs), and can later be remobilized and transported to developing grain. The present study was undertaken to determine the effect of several peduncle (the uppermost internode) morpho-anatomical and biochemical traits on grain weight, and to assess the contribution of the peduncle water-soluble carbohydrate (WSC) reserves shortly after anthesis to its variation. In 2-year field trials, 61 wheat genotypes were used (27 F4:5 families, 17 parents used for the crosses and the 17 current best standards), comparing intact control plants (CP) with plants that were defoliated (DP) by cutting off all leaf blades 10 days after anthesis. Estimated contributions of peduncle (culm (C) and flag LS) assimilate reserves to grain weight/spike were from 0·06 to 0·31 and from 0·11 to 0·45 in CP and DP plants, respectively. In both CP and DP plants, a higher contribution was from the LS than from the C. High peduncle reserve mobilization efficiency, a longer exposed part of the peduncle and larger C storage capacity (through higher parenchyma and/or lower lignified area) were of specific benefit for maintaining grain weight in defoliated plants. F4:5 families had higher transport capacity in the peduncle, but without any improvement in WSC-related traits compared with the best standards.

scholarly journals Accumulation of Antioxidants in Apple Peel as Related to Preharvest Factors and Superficial Scald Susceptibility of the Fruit

1994 ◽  
Vol 119 (2) ◽  
pp. 264-269 ◽  
Author(s):  
Cynthia L. Barden ◽  
William J. Bramlage
Keyword(s):  
Ascorbic Acid ◽  
Low Temperature ◽  
Light Intensity ◽  
Phosphonic Acid ◽  
Malus Domestica ◽  
Water Soluble ◽  
Total Water ◽  
Superficial Scald ◽  
Apple Peel ◽  
Conjugated Trienes

Antioxidants are believed to protect against the oxidation of α-farnesene to conjugated trienes in apple (Malus domestica, Borkh.) peel, thus providing resistance against superficial scald development. We conducted three experiments in which apples were a) harvested weekly, during which they were exposed to increasing hours at <10C during ripening; b) induced to ripen with no hours at <10C by applying ethephon; and c) enclosed in paper bags as they ripened. Inducing ripening with ethephon increased total water-soluble reducing compounds and percentage inhibition of lipid oxidation of peel extracts, increased concentrations of α-tocopherol, carotenoids, and ascorbic acid in peel, but only slightly reduced scald. Delayed harvests increased all of these antioxidants except ascorbic acid and greatly reduced scald development. Bagging fruit before ripening decreased α-tocopherol, carotenoid, and ascorbic acid concentrations, decreased total water-soluble reducing compounds, and increased scald development. We conclude that changes in these antioxidants probably are affected more by ripening and light intensity than by low temperature before harvest. Chemical name used: (2-chloroethyl)phosphonic acid (ethephon).

A Study of Arabidopsis Cold Stress Tolerance Improvement via AthHOS1-Targeting HOS1-AmiRNA Approach

2021 ◽  
Author(s):  
Marzieh Karimi ◽  
Behrouz Shiran ◽  
Mohammad Rabei ◽  
Hossein Fallahi ◽  
Bojana Banović Đeri
Keyword(s):  
Gene Expression ◽  
Arabidopsis Thaliana ◽  
Circadian Rhythm ◽  
Comparative Analysis ◽  
Low Temperature ◽  
Transgenic Plants ◽  
Cold Stress ◽  
Stress Tolerance ◽  
Low Temperatures ◽  
Wild Type

Abstract In this study the artificial microRNAs (amiRNAs) technology targeting HOS1 gene was tested for its applicability for the improvement of cold stress tolerance in Landsberg-0 (Ler-0) ecotype of Arabidopsis thaliana. The chosen approach was designed to suppress AtHOS1 gene expression through the overexpression of amiRNA-HOS1. The effect of AtHOS1-amiRNA overexpression to transgenic plants’ response to cold stress was determined by Real Time PCR. The expression levels of amiRNA and its target, AtHOS1 gene, were observed in 3-week old seedlings of T3 generation and in wild-type plants after 6h, 12h, 24h, 48h and 96h of their exposure to cold stress (4ºC). Comparative analysis revealed that AtHOS1-amiRNA negatively regulated AtHOS1 in transgenic plants upon plants lengthen exposure (for 48h and 96h) to low temperature (Pearson’s correlation coefficient of -0.407; P < 0.05). Even though prolonged cold stress caused extended up regulation of AtHOS1 in wild type plants, in transgenic plants AtHOS1-amiRNA suppression disturbed expected AtHOS1 circadian rhythm by preventing further AtHOS1 up regulation. Moreover, transgenic plants showed AtHOS1 down regulation 96h after the cold stress onset, due to sufficient overexpression of AtHOS1-amiRNA, which allowed cold signaling amplification in transgenic plants. As a result of that, cold-acclimated transformed plants displayed 17% higher freezing tolerance (-1°C to -8°C) in comparison to wild type plants, demonstrating the success of chosen approach in improving Arabidopsis tolerance to low temperatures, at least in Ler-0 ecotype.

scholarly journals (130) Dieffenbachia Calcium Oxalate Crystal Formation Affected by Cultivars, Nitrogen Rates, and Light Intensity

HortScience ◽  
2005 ◽  
Vol 40 (4) ◽  
pp. 1086C-1086
Author(s):  
Hui Cao ◽  
Jianjun Chen ◽  
Dennis B. McConnell
Keyword(s):  
Light Intensity ◽  
Calcium Oxalate ◽  
Cross Section ◽  
Mature Leaf ◽  
Water Soluble ◽  
Cultivar Differences ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Crystal Formation ◽  
Calcium Oxalate Crystal

Tissue-culturedexplantsofDieffenbachiamaculate`Exotic Perfection', D.`Snow Flake', and D. × `Tropic Breeze' were grown on ebb-and-flow trays subirrigated with nitrogen (N) at 50, 200, or 800 mg·L-1 using a water-soluble fertilizer 17N–2.1P–15.7K for 10 weeks in a shaded greenhouse under a maximum photosynthetic photon flux density of 285 μmol·m-2·s-1. Plants were then transferred to interior rooms under a light level of 8 μmol·m-2·s-1. Samples of the midrib were taken from the first mature leaf of plants before being placed indoors and also from the first mature leaf of plants 8 months after growing indoors. Counts of calcium oxalate crystal idioblasts in cross-sections of the basal midrib using polarized light microscopy showed that the number of crystal idioblasts was higher in all three cultivars fertigated with 200 mg·L-1 N than those fertigated with either 50 or 800 mg·L-1 N. The number of crystal idioblasts in each cultivar grown under 8 μmol·m-2·s-1 was about 50% of the number detected when plants were grown under 285 μmol·m-2·s-1. `Snow Flake' had the highest number of crystal idioblasts with counts up to 60 per cross-section, whereas `Exotic Perfection' had the lowest with only 30 per cross-section. This study shows that in addition to cultivar differences, light intensity and N can significantly affect calcium crystal formation, and the highest number of crystal idioblasts occurred when Dieffenbachia cultivars were grown under optimum conditions.

In situ Tensile Experiments at Low Temperatures on Niobium Single Crystals by H.V.E.M.

1975 ◽  
Vol 33 ◽  
pp. 58-59
Author(s):  
F. H. Louchet ◽  
L. P. Kubin
Keyword(s):  
Electron Microscope ◽  
Transition Temperature ◽  
Low Temperature ◽  
Slip System ◽  
Low Temperatures ◽  
Tensile Axis ◽  
Image Intensifier ◽  
Screw Dislocations ◽  
Source Operation

Experiments have been carried out on the 3 MeV electron microscope in Toulouse. The low temperature straining holder has been previously described Images given by an image intensifier are recorded on magnetic tape.The microtensile niobium samples are cut in a plane with the two operative slip directions [111] and lying in the foil plane. The tensile axis is near [011].Our results concern:- The transition temperature of niobium near 220 K: at this temperature and below an increasing difference appears between the mobilities of the screw and edge portions of dislocations loops. Source operation and interactions between screw dislocations of different slip system have been recorded.

INVAR M93

Alloy Digest ◽  
2008 ◽  
Vol 57 (1) ◽  
Keyword(s):  
Fracture Toughness ◽  
Low Temperature ◽  
Physical Properties ◽  
Tensile Properties ◽  
Low Temperatures ◽  
Bend Strength ◽  
Temperature Performance ◽  
Ni Content ◽  
Precision Alloys ◽  
Ni Alloy

Abstract Invar is an Fe-Ni alloy with 36% Ni content that exhibits the lowest expansion of known metals from very low temperatures up to approximately 230 deg C (445 deg F). Invar M93 is a cryogenic Invar with improved weldability. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and shear and bend strength as well as fracture toughness and fatigue. It also includes information on low temperature performance as well as forming and joining. Filing Code: FE-143. Producer or source: Metalimphy Precision Alloys.

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