scholarly journals Environmental factors affecting germination of Mimosa ephedroides (Fabaceae), an endemic shrub from Monte Desert, Argentina

2021 ◽  
Vol 53 (1) ◽  
pp. 139-149
Author(s):  
Sofia Leonor Dágata ◽  
María Emilia Fernández ◽  
Carlos Bernardo Passera
Keyword(s):  
Water Stress ◽  
Environmental Factors ◽  
Room Temperature ◽  
Seed Quality ◽  
Abiotic Factors ◽  
Seed Storage ◽  
Saline Stress ◽  
Severe Water Stress ◽  
Wide Range ◽  
Salinity Levels

Mimosa ephedroides is an endemic shrub from western Argentina. The knowledge of the germination response of this species to different environmental factors contribute to its efficient use in ecological restoration projects. This study aimed to examine aspects of seed quality, seed dormancy, and the effect of temperature, water and saline stress on the germination of this species. Also, the effect of seed storage time on the viability and the percentage of germinated seeds were evaluated. Experiments were carried out in controlled growth chambers. Germination percentage and mean germination time were calculated. It was found that this species has non-dormant seeds. Concerning abiotic factors, the optimum temperature for germination ranged from 20 to 30 ºC, it presented high germination percentages even at moderate and severe water stress (-1.12 MPa), and the germination percentages decreased with increasing salinity levels from 300 mM NaCl. In short periods (up to 36 months), seed storage at room temperature (18ºC) was adequate, not affecting the viability and the germination power of the seeds. These results constitute a contribution to the knowledge of the autecological aspects of this endemic species, support its incorporation for restoration projects, and aid to an efficient use of native seeds for direct seeding or seedling production. Highlights Mimosa ephedroides seeds are non- dormant, show high viability and rapid germination (>24 h). This shrub is able to germinate in a wide range of temperatures and under moderate and severe water stress. High salinity levels (<300 Mm NaCl) negatively affected seed germination. Seed storage for short periods (<5 years) at room temperature (18ºC) did not affect seed viability and germination.

scholarly journals Influence of abiotic factors on seed quality of maize hybrids in the process of its storage

2021 ◽  
Vol 5 (1) ◽  
pp. 30-37
Author(s):  
M. Ya. Kyrpa ◽  
Yu. S. Bazilieva ◽  
O. F. Stasiv
Keyword(s):  
Growth Rate ◽  
Moisture Content ◽  
Chemical Treatment ◽  
Seed Quality ◽  
Abiotic Factors ◽  
Seed Mass ◽  
Seed Storage ◽  
Maize Hybrids ◽  
Storage Methods

The research results of influence of various abiotic factors on seed quality of maize hybrids during long storage are given. The most effective of them are: temperature regime, seed moisture content and oxygen access. The storage methods (dry and cold, and controlled atmosphere storage) that have the greatest impact on the seed quality were established. It was found that the optimal moisture content of seed depends on the storage duration, if for 1–2 years – 10–11 %, 3 years and more – 7–8 %. In order to stabilize the moisture content, it is recommended to store the seeds in airtight containers, limiting the humidity access from the outside. During the long-term seed storage, particularly for the breeding purposes, the temperature range should advisably maintain within 8–10 °C in seed storage place. With that the laboratory germination of seeds increased by 3–5 %, field germination – by 6–8 %, growth rate by number of sprouts– by 5–9 % and by the weight of sprouts – by 2–5 g compared to the 18–20 °C temperature in a typical storage. Methods of pre-sowing improvement of seed quality were established – it is separation and chemical treatment (seed dressing). Separation is the sifting of the seed mass through sieves with round holes in order to divide from the smallest fraction, the content of which was 15–23 % depending on the seed uniformity of maize hybrids. It was found that in order to assess objectively the effectiveness of different chemicals and establish their suitability for presowing seed treatment, it is necessary to determine laboratory germination, especially the growth rate by the number of sprouts and weight of 100 sprouts. Premature chemical treatment of seed should be avoided. Key words: maize hybrids, storage methods, abiotic factors, seed quality, presowing treatment.

Coupling anaerobic bacteria and microbial fuel cells as whole-cell environmental biosensors

2015 ◽  
Vol 36 (3) ◽  
pp. 129 ◽  
Author(s):  
Lara T Bereza-Malcolm ◽  
Ashley E Franks
Keyword(s):  
Environmental Factors ◽  
Microbial Fuel Cells ◽  
Abiotic Factors ◽  
Anaerobic Bacteria ◽  
Whole Cell ◽  
Biologically Relevant ◽  
Anaerobic Microorganisms ◽  
Wide Range ◽  
Relevant Factors

Microorganisms have evolved to respond to environmental factors allowing adaption to changing conditions and minimisation of potential harm. Microbes have the ability to sense a wide range of biotic and abiotic factors including nutrient levels, analytes, temperature, contaminants, community quorum, and metabolic activity. Due to this ability, the use of whole-cell microbes as biosensors is attractive as it can provide real-time in situ information on biologically relevant factors through qualitative and quantitative outputs. Interestingly, many of the environments where these biosensors will be of most of use lack oxygen; and as such the use of anaerobic microorganisms to sense environmental factors with easy to use outputs is essential. Furthermore, sensing of contaminants can be linked with bioremediation of known contaminated environments, allowing a flexible, multiplexed device.

scholarly journals Seed germination of a rare neotropical canopy tree dormancy and the effects of abiotic factors

2010 ◽  
Vol 34 (3) ◽  
pp. 443-449 ◽  
Author(s):  
Flavio Nunes Ramos ◽  
Antonio Carlos Silva de Andrade
Keyword(s):  
Water Stress ◽  
Seed Germination ◽  
Environmental Factors ◽  
Abiotic Factors ◽  
Seed Longevity ◽  
Seed Availability ◽  
Canopy Tree ◽  
Critical Phase ◽  
One Year

The purpose of this study was to examine if germination is a critical phase on Enterolobium glaziovii regeneration. Hence, the germinative response of E. glaziovii seeds was investigated in relation to some of the main environmental factors (temperature, light and water stress) to which its seeds are subjected in the forest, as well as its dormancy and the longevity of its burial seeds. According to our results, its seeds may be regarded as photoblastic neutral. They do not need alternating temperatures to germinate and can germinate under a broad range of water stress. However, only about 10% of E. glaziovii seeds remain viable after one year. In other words, the annual fruiting, instead seed longevity, seems to maintain the long-term seed availability of this species. Consequently, the seed longevity could be a critical phase of E. glaziovii germination.

scholarly journals Viabilitas Benih Bawang Putih Varietas Tawang Mangu Setelah Penyimpanan pada Berbagai Suhu

2019 ◽  
Vol 2 (3) ◽  
pp. 43
Author(s):  
. Sulassih ◽  
Yohanes Aris Purwanto ◽  
. Sobir ◽  
Naekman Naibaho ◽  
Siaga Yudha Pratama ◽  
...  
Keyword(s):  
Weight Loss ◽  
High Temperature ◽  
Moisture Content ◽  
Room Temperature ◽  
Seed Quality ◽  
Light Condition ◽  
Seed Storage ◽  
Physical Damage ◽  
Small Weight ◽  
Field Emergence

Viability of garlic seed is important for seed quality. Periode of seed storage Penyimpanan benih berkaitan dengan viabilitas benih. Viability testing measured after storage at 0 oC, 7 oC and room temperate. Moisture content decreased (40-45%) after 1 month in the storage under light condition, but the weight loss approximately at 1-8%, still lower than ASEAN rules (2009) that is not over than 10-15% for physical damage. Tawang Mangu variety showed higher for percentage of field emergence (83.33%) after was storages at 0 oC for one month and produced higher bulb (11 bulbs), but at the room temperature showed the lower for percentage of field emergence (56.94%) and produced 2-3 bulbs. All the treatment (7oC and room temperature) produced small size of bulbs in weight (1-2 g), height (1.5-1.7 cm) and width (1.5-1.6 cm). Three of the temperature condition was produced single bulb called “bawang lanang”, it suggested causing the land unfertilizer. Garlic was not suitable for medium land and high temperature such as Bogor.Keywords: diameter, height, male garlic, small, weight

scholarly journals Effects of Salinity on Physiological, Biochemical and Gene Expression Parameters of Black Tiger Shrimp (Penaeus monodon): Potential for Farming in Low-Salinity Environments

Biology ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1220
Author(s):  
Md. Lifat Rahi ◽  
Khairun Naher Azad ◽  
Maliha Tabassum ◽  
Hasna Hena Irin ◽  
Kazi Sabbir Hossain ◽  
...  
Keyword(s):  
Abiotic Factors ◽  
Penaeus Monodon ◽  
Production Performance ◽  
Growth And Survival ◽  
Factors Affecting ◽  
Black Tiger Shrimp ◽  
Low Salinity ◽  
Tiger Shrimp ◽  
Wide Range ◽  
Salinity Levels

Salinity is one of the most important abiotic factors affecting growth, metabolism, immunity and survival of aquatic species in farming environments. As a euryhaline species, the black tiger shrimp (Penaeus monodon) can tolerate a wide range of salinity levels and is farmed between brackish to marine water conditions. The current study tested the effects of six different salinity levels (0‰, 2.5‰, 5‰, 10‰, 20‰ and 30‰) on the selected physiological, biochemical and genetic markers (individual changes in the expression pattern of selected candidate genes) in the black tiger shrimp. Experimental salinity levels significantly affected growth and survival performance (p < 0.05); the highest levels of growth and survival performance were observed at the control (20‰) salinity. Salinity reductions significantly increased free fatty acid (FFA), but reduced free amino acid (FAA) levels. Lower salinity treatments (0–10‰) significantly reduced hemolymph osmolality levels while 30‰ significantly increased osmolality levels. The five different salinity treatments increased the expression of osmoregulatory and hemolymph regulatory genes by 1.2–8-fold. In contrast, 1.2–1.6-fold lower expression levels were observed at the five salinity treatments for growth (alpha amylase) and immunity (toll-like receptor) genes. O2 consumption, glucose and serotonin levels, and expression of osmoregulatory genes showed rapid increase initially with salinity change, followed by reducing trend and stable patterns from the 5th day to the end. Hemocyte counts, expression of growth and immunity related genes showed initial decreasing trends, followed by an increasing trend and finally stability from 20th day to the end. Results indicate the farming potential of P. monodon at low salinity environments (possibly at freshwater) by proper acclimation prior to stocking with minimal effects on production performance.

Influence of selected environmental factors on glyphosate efficacy when applied to awnless barnyard grass (Echinochloa colona (L.) Link)

1997 ◽  
Vol 48 (5) ◽  
pp. 695 ◽  
Author(s):  
Songyod Tanpipat ◽  
Steve W. Adkins ◽  
John T. Swarbrick ◽  
Mark Boersma
Keyword(s):  
Soil Moisture ◽  
Water Stress ◽  
Relative Humidity ◽  
Environmental Factors ◽  
Field Capacity ◽  
Barnyard Grass ◽  
Temperature Regimes ◽  
Severe Water Stress ◽  
Moisture Conditions

Glasshouse experiments were conducted to determine the effects of various environmental factors on glyphosate efficacy when applied to Echinochloa colona (L.) Link (awnless barnyard grass) plants. The variables examined were 4 soil moisture conditions (29, 42, 55, and 100% of field capacity), 2 levels of irradiance (400 and 800 µmol/m2· s), 3 temperature regimes (20/15, 30/25, and 35/30°C; day/night), and 2 levels of relative humidity (92 and 65%). The efficacy of 360 g acid equivalent glyphosate/ha was greatest when applied to well-watered (field capacity) plants that were placed under cool (20/25°C) and humid (92% relative humidity) conditions. The efficacy was least when applied to plants under severe water stress (29% of field capacity) that were placed under hot (35/30°C) and less humid (65% relative humidity) conditions. In all experiments, efficacy was not altered by the level of irradiance.

Factors Affecting Germination of Citronmelon (Citrullus lanatusvar.citroides)

Weed Science ◽  
2014 ◽  
Vol 62 (1) ◽  
pp. 45-50 ◽  
Author(s):  
Analiza Henedina M. Ramirez ◽  
Amit J. Jhala ◽  
Megh Singh
Keyword(s):  
Water Stress ◽  
Environmental Factors ◽  
Climatic Conditions ◽  
Dark Condition ◽  
Light Conditions ◽  
Factors Affecting ◽  
Wide Range ◽  
Citrus Orchards ◽  
Favorable Weather ◽  
Effect Of Light

Citron melon is a monoecious, hairy annual vine commonly found in citrus orchards, and cotton and peanut fields. Information is not available on the effect of various environmental factors on the germination of citron melon. Laboratory and greenhouse experiments were carried out in 2011 and 2012 to determine the effect of light, temperature, salinity, pH, simulated water stress, and depth of sowing on the germination of citron melon. Citron melon germination was affected by various environmental factors. Highest germination was observed at day/night temperatures of 25/20 to 30/25 C regardless of light conditions. At temperatures below 25 C and beyond 35 C, germination declined and was higher under dark condition than light. Germination decreased as osmotic potential became more negative (−0.3 MPa to −1.5 MPa) and salt concentration increased (50 to 350 mM). No germination was observed at > −0.9 MPa and ≥ 300 mM salt concentrations. However, germination was observed over a broad range of pH (3 to 9) and up to 10-cm sowing depths. Seeds sown at the surface did not germinate but maximum germination (88 to 96%) occurred at 2- to 4-cm depth. The results of this study suggest that citron melon can grow in a wide range of climatic conditions and therefore can persist in Florida because of favorable weather and environmental conditions.

scholarly journals Population-based Models of Seed Viability Loss during Storage: What's the Use?

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 910C-910 ◽  
Author(s):  
Kent J. Bradford
Keyword(s):  
Seed Quality ◽  
Quantitative Description ◽  
Seed Viability ◽  
Seed Storage ◽  
Population Based ◽  
Probit Analysis ◽  
Seed Longevity ◽  
Seed Industry ◽  
Wide Range ◽  
Precise Quantification

In 1981, R.H. Ellis and E.H. Roberts published a classic paper on the quantification of aging and survival in seeds (Seed Sci. & Technol. 9:373). This paper and subsequent refinements described a model of seed aging in storage that was based on the fact that to a good approximation, deaths over time in a seed population are normally distributed. The model provides a quantitative description of seed longevity across a wide range of storage temperatures and moisture contents. Despite its theoretical importance and practical success, the Ellis–Roberts approach has not been widely adopted by the seed industry to assess seed quality and predict longevity in storage. This may be due, in part, to the rather unfamiliar statistics (probit analysis) used in the model and the apparent complexity of the equations. It will be the argument of this presentation, however, that the precise quantification of seed longevity that this model affords is less significant than the insight that it provides into the nature of seed populations and how to think about them. The objective of this presentation will be to demystify the Ellis–Roberts model and illustrate with concrete examples how the application of population-based thinking is advantageous in many aspects of seed storage and quality assessment.

scholarly journals Germination and vigour in genotypes of forage sorghum at different levels of water and salt stress

2020 ◽  
pp. 1975-1986
Author(s):  
Luma Rayane de Lima Nunes ◽  
Miller Clementino Cruz ◽  
Charles Lobo Pinheiro ◽  
Geocleber Gomes de Sousa ◽  
Alek Sandro Dutra
Keyword(s):  
Salt Stress ◽  
Water Stress ◽  
Arid Regions ◽  
Abiotic Factors ◽  
Dry Weight ◽  
Germination Percentage ◽  
Saline Stress ◽  
Strong Impact ◽  
Forage Sorghum ◽  
Different Levels

Salinity and water deficiency are abiotic factors which have a strong impact on agricultural activities, especially in arid and semi-arid regions. The aim of this research was to analyse the tolerance of two genotypes of forage sorghum, EA 116 and BRS Ponta Negra, to different levels of water and salt stress during germination. The conditions of water and salt stress were simulated by moistening the substrate with a solution of mannitol and of sodium chloride (NaCl) respectively, with the water potential adjusted to 0 (distilled water), -0.1, -0.2, -0.3, -0.4, -0.5 and -0.6 MPa. The variables under analysis were germination percentage, first count, germination speed index, shoot and root length, seedling dry weight, electrolyte leakage and leaf Na+/K+ ratio. The experiment was conducted in a completely randomised design, and distributed in a 2 (genotypes) × 2 (stress condition) × 7 (osmotic potential) factorial scheme, with four replications. The EA 116 and BRS Ponta Negra genotypes show greater tolerance to water stress. The EA 116 cultivar maintained germination under water stress from 0 to -0.6 MPa and saline stress from 0 to -0.4 MPa.

Mechanical Properties and Dislocation Structure of Single Crystal Cdte Deformed in Compression at 300°C

1976 ◽  
Vol 34 ◽  
pp. 592-593
Author(s):  
Ernest L. Hall ◽  
J. B. Vander Sande
Keyword(s):  
Mechanical Properties ◽  
Single Crystal ◽  
Dislocation Structure ◽  
Room Temperature ◽  
Elevated Temperatures ◽  
Strain Curve ◽  
Optical Devices ◽  
Semiconductor Compound ◽  
Wide Range ◽  
Sample Orientation

The present paper describes research on the mechanical properties and related dislocation structure of CdTe, a II-VI semiconductor compound with a wide range of uses in electrical and optical devices. At room temperature CdTe exhibits little plasticity and at the same time relatively low strength and hardness. The mechanical behavior of CdTe was examined at elevated temperatures with the goal of understanding plastic flow in this material and eventually improving the room temperature properties. Several samples of single crystal CdTe of identical size and crystallographic orientation were deformed in compression at 300°C to various levels of total strain. A resolved shear stress vs. compressive glide strain curve (Figure la) was derived from the results of the tests and the knowledge of the sample orientation.

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