Ecophysiology germination of Senna uniflora seeds: species for recovery degraded areas

Abstract: Studies on seeds ecophysiology are important to understanding of adaptation mechanisms and of species´ tolerance limits to natural conditions, because determine the potential of use in recovery plans of degraded areas. The aim of this study was to characterize and assess the effect of different temperatures, methods of dormancy overcoming and water and salt stresses on the germination of Senna uniflora. Imbibition curve and germination assay were conducted to assess the effect of temperature regimes (20 °C, 25 °C, 30 °C, 35 °C, 40 °C and 20-30 °C), of methods of overcoming dormancy (without scarification, mechanical scarification, chemical scarification and thermal scarification) and of water and salt stresses at the osmotic potentials (0.0; -0.2; -0.4 and -0.8 MPa) . The assessed variables were germination, germination speed index and average germination time. Methods of mechanical and chemical scarification for 5, 15 and 30 min were efficient to overcome physical dormancy, especially on constant temperature regimes of 25 °C and 30 °C and alternated 20-30 °C. Submitted to conditions of water and salt stresses, seeds germination was reduced with the increase of the osmotic potential, being -0.8 MPa the germination minimum limit, in addition, seeds were more sensitive to water stress than to salt stress.

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The effect of temperature on persistence of SARS-CoV-2 on common surfaces

Virology Journal ◽

10.1186/s12985-020-01418-7 ◽

2020 ◽

Vol 17 (1) ◽

Cited By ~ 25

Author(s):

Shane Riddell ◽

Sarah Goldie ◽

Andrew Hill ◽

Debbie Eagles ◽

Trevor W. Drew

Keyword(s):

Uv Light ◽

Risk Mitigation ◽

Survival Rates ◽

Environmental Stability ◽

Effect Of Temperature ◽

Viral Loads ◽

Different Temperatures ◽

C 30 ◽

D Values

Abstract Background The rate at which COVID-19 has spread throughout the globe has been alarming. While the role of fomite transmission is not yet fully understood, precise data on the environmental stability of SARS-CoV-2 is required to determine the risks of fomite transmission from contaminated surfaces. Methods This study measured the survival rates of infectious SARS-CoV-2, suspended in a standard ASTM E2197 matrix, on several common surface types. All experiments were carried out in the dark, to negate any effects of UV light. Inoculated surfaces were incubated at 20 °C, 30 °C and 40 °C and sampled at various time points. Results Survival rates of SARS-CoV-2 were determined at different temperatures and D-values, Z-values and half-life were calculated. We obtained half lives of between 1.7 and 2.7 days at 20 °C, reducing to a few hours when temperature was elevated to 40 °C. With initial viral loads broadly equivalent to the highest titres excreted by infectious patients, viable virus was isolated for up to 28 days at 20 °C from common surfaces such as glass, stainless steel and both paper and polymer banknotes. Conversely, infectious virus survived less than 24 h at 40 °C on some surfaces. Conclusion These findings demonstrate SARS-CoV-2 can remain infectious for significantly longer time periods than generally considered possible. These results could be used to inform improved risk mitigation procedures to prevent the fomite spread of COVID-19.

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Seeds of Caesalpinia echinata Lam. Under Water Stress at Different Temperatures

Journal of Agricultural Science ◽

10.5539/jas.v12n7p66 ◽

2020 ◽

Vol 12 (7) ◽

pp. 66

Author(s):

Caroline Marques Rodrigues ◽

Edna Ursulino Alves ◽

Rosemere dos Santos Silva ◽

Flávio Ricardo da Silva Cruz ◽

Maria Lúcia Maurício da Silva ◽

...

Keyword(s):

Water Stress ◽

Economic Value ◽

Seed Vigor ◽

Large Tree ◽

Randomized Design ◽

Different Temperatures ◽

C 30 ◽

Caesalpinia Echinata ◽

Polyethylene Glycol 6000 ◽

Osmotic Potentials

The Caesalpinia echinata Lam. species, belongs to the Fabaceae family, popularly known as Pau Brazil, is a large tree, native to Brazil, that can be found from Ceará to Rio de Janeiro, with a relevant national historic and economic value. The objective of this study was to evaluate the effects of water stress at different temperatures on germination and seed vigor. The experiment was carried out at the Laboratório de Análise de Sementes of the Centro de Ciências Agrárias of the Universidade Federal da Paraíba, Areia-Paraíba. The water stress was formulated with solutions of polyethylene glycol 6000 (PEG 6000) in different osmotic potentials of 0.0 (control), -0.2; -0.4; -0.6 MPa at constant temperatures of 25, 30 and 35 °C, in a completely randomized design. The percentage of germination, first counting of germination, germination speed index, length and dry matter of seedlings were evaluated to determine the effects of the treatments. Decreases of the osmotic potential negatively influenced the germination and vigor of C. echinata seeds at the three evaluated temperatures (25 ºC, 30 ºC, 35 °C).

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Effect of Different Temperature Regimes on the Germination of Pseudolysimachion pusanensis (Y. N. Lee) Y. N. Lee Seeds

Horticulturae ◽

10.3390/horticulturae7120577 ◽

2021 ◽

Vol 7 (12) ◽

pp. 577

Author(s):

Mi-Hyun Lee ◽

Jin-Hyun Lim ◽

Cho-Hee Park ◽

Jun-Hyeok Kim ◽

Chae-Sun Na

Keyword(s):

Native Plants ◽

Germination Percentage ◽

Storage Management ◽

Base Temperature ◽

Temperature Regimes ◽

Different Temperatures ◽

Mean Germination Time ◽

The Mean ◽

C 30 ◽

Gradient Plate

In this study, we determined the germination response in the seeds of the rare plant Pseudolysimachion pusanensis (Y. N. Lee) Y. N. Lee to different temperatures. P. pusanensis seeds were collected from the Baekdudaegan National Arboretum, South Korea, in November 2019, and dried. Dry seeds were placed at constant and alternating temperatures (5 °C, 10 °C, 15 °C, 20 °C, 25 °C, 30 °C, and 35 °C) to determine their germination percentage (GP). The seeds were exposed to 59 temperature combinations ranging from 5 °C to 43 °C using a thermal gradient plate. The photoperiod was set at 12:12 h (light:dark) and germination assays were performed five times a week. Subsequently, the seed GP and the number of days required to reach 50% of the germination (T50) were determined. The highest final GP was 94.38%, with a T50 value of 9.26 d at 15 °C. However, the mean germination time was 12.5 d at 15 °C, and linear regression using 1/T50 revealed that the base temperature ranged from 2.69 °C to 4.68 °C. These results for P. pusanensis seeds stored in a seed bank provide useful data for the native plants horticulture industry and can also be utilized for storage management.

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The effect of temperature on cold hardening of Loliutn perenne seedlings

The Journal of Agricultural Science ◽

10.1017/s0021859600029300 ◽

1980 ◽

Vol 95 (1) ◽

pp. 77-81 ◽

Cited By ~ 14

Author(s):

M. P. Fuller ◽

C. F. Eagles

Keyword(s):

Lolium Perenne ◽

Low Temperatures ◽

Cold Hardiness ◽

Leaf Growth ◽

Effect Of Temperature ◽

Threshold Temperature ◽

Screening Techniques ◽

Temperature Regimes ◽

Different Temperatures ◽

Cool Night

SummaryThe variation in hardening responses under different temperature regimes for three cultivars of Lolium perenne L. is described. The relative cold hardiness of the cultivars was modified by different temperatures during hardening. A threshold temperature existed above which hardening did not occur, but this temperature varied between cultivars.Although continuous low temperatures (2 °C) favoured hardening, hardening also occurred under warm day and cool night conditions (15:2 °C) where cultivars showed contrasting hardiness responses in daylengths of 16, 12 and 8 h. Under some of these conditions both leaf growth and hardiness were possible.The significance of these results is discussed in terms of the development of screening techniques and breeding objectives.

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The Effects of Temperature on the Stiffness Modulus of Dense Graded Asphalt Mixtures

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.423-426.997 ◽

2013 ◽

Vol 423-426 ◽

pp. 997-1000

Author(s):

Ali Mohamed Abudullahi ◽

Kwong Yiing Ting ◽

Wee Kang Choong ◽

Boon Hoe Goh

Keyword(s):

Design Method ◽

Effect Of Temperature ◽

Asphaltic Concrete ◽

Stiffness Modulus ◽

Different Temperatures ◽

Indirect Tensile ◽

N Loading ◽

C 30 ◽

Styrene Butadiene

This study aimed to investigate the effect of temperature on stiffness modulus of asphaltic concrete. The asphaltic concrete mixture were prepared based on Marshall Mix Design method using two different types of bitumen, the 80/100 penetration grade bitumen (80/100 PGB) and Styrene-Butadiene-Styrene (SBS), both with five percent bitumen content. Indirect Tensile Stiffness Modulus (ITSM) test of 1000 N loading was then performed at three different temperatures (25 °C, 30 °C and 40 °C). The results showed that stiffness modulus decreases with increases in temperature for both 80/100 PGB and SBS, which shows the important role of temperature to stiffness modulus of asphaltic concrete. Also, the results showed a higher stiffness modulus for SBS mixtures compare to that of 80/100 PGB mixtures.

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The Respiration of some Planktonic copepods II. The Effect Of Temperature

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400011607 ◽

1953 ◽

Vol 31 (3) ◽

pp. 447-460 ◽

Cited By ~ 28

Author(s):

D. T. Gauld ◽

J. E. G. Raymont

Keyword(s):

Respiratory Rate ◽

The Body ◽

The Other ◽

Effect Of Temperature ◽

Acartia Clausi ◽

Temora Longicornis ◽

Different Temperatures ◽

Planktonic Copepods ◽

The Difference ◽

The Relationship

The respiratory rates of three species of planktonic copepods, Acartia clausi, Centropages hamatus and Temora longicornis, were measured at four different temperatures.The relationship between respiratory rate and temperature was found to be similar to that previously found for Calanus, although the slope of the curves differed in the different species.The observations on Centropages at 13 and 170 C. can be divided into two groups and it is suggested that the differences are due to the use of copepods from two different generations.The relationship between the respiratory rates and lengths of Acartia and Centropages agreed very well with that previously found for other species. That for Temora was rather different: the difference is probably due to the distinct difference in the shape of the body of Temora from those of the other species.The application of these measurements to estimates of the food requirements of the copepods is discussed.

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Effect of temperature, CO2 and O2 on motility and mobility of Anisakidae larvae

Scientific Reports ◽

10.1038/s41598-021-83505-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Aiyan Guan ◽

Inge Van Damme ◽

Frank Devlieghere ◽

Sarah Gabriël

Keyword(s):

Enzymatic Digestion ◽

Infected Fish ◽

Effect Of Temperature ◽

Video Recordings ◽

Different Temperatures ◽

Semi Solid ◽

Zoonotic Parasites ◽

The Impact ◽

Phosphate Buffered Saline

AbstractAnisakidae, marine nematodes, are underrecognized fish-borne zoonotic parasites. Studies on factors that could trigger parasites to actively migrate out of the fish are very limited. The objective of this study was to assess the impact of different environmental conditions (temperature, CO2 and O2) on larval motility (in situ movement) and mobility (migration) in vitro. Larvae were collected by candling or enzymatic digestion from infected fish, identified morphologically and confirmed molecularly. Individual larvae were transferred to a semi-solid Phosphate Buffered Saline agar, and subjected to different temperatures (6 ℃, 12 ℃, 22 ℃, 37 ℃) at air conditions. Moreover, different combinations of CO2 and O2 with N2 as filler were tested, at both 6 °C and 12 °C. Video recordings of larvae were translated into scores for larval motility and mobility. Results showed that temperature had significant influence on larval movements, with the highest motility and mobility observed at 22 ℃ for Anisakis spp. larvae and 37 ℃ for Pseudoterranova spp. larvae. During the first 10 min, the median migration of Anisakis spp. larvae was 10 cm at 22 ℃, and the median migration of Pseudoterranova spp. larvae was 3 cm at 37 ℃. Larval mobility was not significantly different under the different CO2 or O2 conditions at 6 °C and 12 ℃. It was concluded that temperature significantly facilitated larval movement with the optimum temperature being different for Anisakis spp. and Pseudoterranova spp., while CO2 and O2 did not on the short term. This should be further validated in parasite-infected/spiked fish fillets.

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Effect of Temperature during Drying and Storage of Dried Figs on Growth, Gene Expression and Aflatoxin Production

Toxins ◽

10.3390/toxins13020134 ◽

2021 ◽

Vol 13 (2) ◽

pp. 134

Author(s):

Ana Isabel Galván ◽

Alicia Rodríguez ◽

Alberto Martín ◽

Manuel Joaquín Serradilla ◽

Ana Martínez-Dorado ◽

...

Keyword(s):

Gene Expression ◽

Aflatoxin Production ◽

Effect Of Temperature ◽

Mycotoxin Production ◽

Industrial Processing ◽

Factors Associated ◽

Different Temperatures ◽

Major Producer ◽

Main Factors ◽

And Storage

Dried fig is susceptible to infection by Aspergillus flavus, the major producer of the carcinogenic mycotoxins. This fruit may be contaminated by the fungus throughout the entire chain production, especially during natural sun-drying, post-harvest, industrial processing, storage, and fruit retailing. Correct management of such critical stages is necessary to prevent mould growth and mycotoxin accumulation, with temperature being one of the main factors associated with these problems. The effect of different temperatures (5, 16, 25, 30, and 37 °C) related to dried-fig processing on growth, one of the regulatory genes of aflatoxin pathway (aflR) and mycotoxin production by A. flavus, was assessed. Firstly, growth and aflatoxin production of 11 A. flavus strains were checked before selecting two strains (M30 and M144) for in-depth studies. Findings showed that there were enormous differences in aflatoxin amounts and related-gene expression between the two selected strains. Based on the results, mild temperatures, and changes in temperature during drying and storage of dried figs should be avoided. Drying should be conducted at temperatures >30 °C and close to 37 °C, while industry processing, storage, and retailing of dried figs are advisable to perform at refrigeration temperatures (<10 °C) to avoid mycotoxin production.

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Corrosion Behaviour of 316L Stainless Steel in CNTs–Water Nanofluid: Effect of Temperature

Materials ◽

10.3390/ma14010119 ◽

2020 ◽

Vol 14 (1) ◽

pp. 119

Author(s):

Dana H. Abdeen ◽

Muataz A. Atieh ◽

Belabbes Merzougui

Keyword(s):

Stainless Steel ◽

316L Stainless Steel ◽

Corrosion Behaviour ◽

Gum Arabic ◽

Steel Sample ◽

Open Circuit ◽

Deionized Water ◽

Effect Of Temperature ◽

Different Temperatures ◽

In Series

The inhibition behavior of carbon nanotubes (CNTs) and Gum Arabic (GA) on the corrosion of 316L stainless steel in CNTs–water nanofluid under the effect of different temperatures was investigated by electrochemical methods and surface analysis techniques. Thereby, 316L stainless steel samples were exposed to CNTs–water nanofluid under temperatures of 22, 40, 60 and 80 °C. Two concentrations of the CNTs (0.1 and 1.0 wt.% CNTs) were homogenously dispersed in deionized water using the surfactant GA and tested using three corrosion tests conducted in series: open circuit test, polarization resistance test, and potentiodynamic scans. These tests were also conducted on the same steel but in solutions of GA-deionized water only. Tests revealed that corrosion increases with temperature and concentration of the CNTs–water nanofluids, having the highest corrosion rate of 32.66 milli-mpy (milli-mil per year) for the 1.0 wt.% CNT nanofluid at 80 °C. In addition, SEM observations showed pits formation around areas of accumulated CNTs that added extra roughness to the steel sample. The activation energy analysis and optical surface observations have revealed that CNTs can desorb at higher temperatures, which makes the surface more vulnerable to corrosion attack.

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Effect of temperature on composite films made with activated carbon, graphite, or graphene oxide (GO) in a gelatin matrix

BioResources ◽

10.15376/biores.16.1.77-95 ◽

2020 ◽

Vol 16 (1) ◽

pp. 77-95

Author(s):

Siqiao Yang ◽

Haichao Li

Keyword(s):

Contact Angle ◽

Activated Carbon ◽

Water Absorption ◽

Composite Films ◽

Effect Of Temperature ◽

Gelatin Matrix ◽

Vapour Permeability ◽

Blending Method ◽

The Matrix ◽

Different Temperatures

Activated carbon, graphite, and GO/gelatin composite films were prepared by the blending method. The properties of composites were characterized by tensile strength (TS), elongation at break (EB), water vapour permeability (WVP), water-absorption ability, contact angle, scanning electron microscopy (SEM), and moisture at different temperatures. The properties of GO/gelatin composite films were better when each of three kinds of carbon materials were used as reinforcement phases and added into the matrix gelatin. The results showed that EB and TS of GO/gelatin composite films were both excellent. The moisture of GO/gelatin composite films was greater than the others. SEM micrographs showed that GO had better compatibility and dispersibility with gelatin than activated carbon and graphite. The water absorption of GO/gelatin composite films were low, at 15 °C and 25 °C, and the WVP was low at 35 °C. The WVP of GO/gelatin composite films was lower than the others at different temperatures. The contact angle of GO/gelatin composite films was larger than the others.

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