Imbibition Temperature Research Articles

The effects of various factors on spontaneous imbibition in tight oil reservoirs

Slickwater fracturing fluids have gained widespread application in the development of tight oil reservoirs. After the fracturing process, the active components present in slickwater can directly induce spontaneous imbibition within the reservoir. Several variables influence the eventual recovery rate within this procedure, including slickwater composition, formation temperature, degree of reservoir fracture development, and the reservoir characteristics. Nonetheless, the underlying mechanisms governing these influences remain relatively understudied. In this investigation, using the Chang-7 block of the Changqing Oilfield as the study site, we employ EM-30 slickwater fracturing fluid to explore the effects of the drag-reducing agent concentration, imbibition temperature, core permeability, and core fracture development on spontaneous imbibition. An elevated drag-reducing agent concentration is observed to diminish the degree of medium and small pore utilization. Furthermore, higher temperatures and an augmented permeability enhance the fluid flow properties, thereby contributing to an increased utilization rate across all pore sizes. Reduced fracture development results in a lower fluid utilization across diverse pore types. This study deepens our understanding of the pivotal factors affecting spontaneous imbibition in tight reservoirs following fracturing. The findings act as theoretical, technical, and scientific foundations for optimizing fracturing strategies in tight oil reservoir transformations.

Influence of imbibition temperature on the extraction stage of the cane sugar production

The effect of the imbibition temperature on the operational performance of the extraction stage is not fully clarified. Additionally, many criteria referred to on this issue are contradictory, inconclusive, or not supported by industrial data. Due to such limitations in knowledge, this research aims to analyze the influence of imbibition temperature on: i) temperature of the milling train juices, ii) moisture and sucrose composition of bagasse, and iii) starch composition of milling train juices. The results indicate that the imbibition temperature has no influence on the mixed juice temperature and does not allow the minimum recommended temperature for asepsis (65 °C) in all juices of the milling units to be reached. Moreover, from the experiments performed, it is established that bagasse moisture increases by 1.6–1.8 units, and sucrose extraction reduces by 12% when the imbibition temperature varies from 85 °C to 40 °C. The starch composition of the mixed juice increases by 15% when the imbibition temperature rises from 40 °C to 85 °C. The research provides new statistical evidence for a better understanding and operational control of the effect of imbibition temperature.

Bromelain crude extract to improve the emergence and growth of pepper seedlings

Pepper (Capsicum annuum L.) is one of the most consumed horticultural products worldwide. However, pepper seeds have slow and asynchronous germination. Organic agriculture encourages using natural substances for the pre-germinative treatment of seeds. The objective of the present work was to evaluate the effect of priming sweet pepper seeds with bromelain crude extract (obtained from pineapple stem residues) on subsequent seedling emergence and growth. The effects of the proteolytic activity of the extract (0, 3.16, 6.25, 12.25, and 25.0 totalU), imbibition time (0, 3, 6, 9, 12, and 15 h), and imbibition temperature (15, 25, 35 and 45 ℃) on seedling emergence and growth were assessed. The significantly best emergence, based on a range of indicators (emergence percentage: E, time to 50% emergence: TE50, emergence index: EI, mean emergence rate: MER, mean emergence time: MET, and synchronization index: SI), was obtained when the seeds were treated for three h at 35°C with a 6.25 totalU bromelain crude extract. Seeds subjected to this treatment combination also yielded the most vigorous seedlings (number of true leaves, length and thickness of the stems, fresh mass, dry mass, leaf area) . In conclusion, pre-germinative treatment with bromelain crude extract of 6.25 totalU proteolytic activity for three h at 35°C improved seedling emergence and growth in sweet pepper seedlings relative to untreated seed. This result offers an organic priming alternative for seeds of sweet pepper.

Desempenho fisiológico de sementes de Zea mays matricondicionadas em diferentes temperaturas

The use of high quality seeds reflects directly on crop establishment and productivity. The speed of seed water intake, as well as, temperature during this process is the main factor to have success during germination. The objective of this study was quantifying water uptake from corn seeds during matriconditioning under four temperatures (10, 15, 20 and 25 °C) and seeds without treatment (control) also evaluate physiological quality of those. C1 seed, without chemical treatment, from two different lots of 30F53YH hybrid corn was used. The water content curve was determined from eight replication,of two hundred seeds each, by weighing in intervals of 2; 4; 6; 10; 14; 18; and 24 hours of soaking. In sequence various tests aiming identify physiological seeds quality was developed. With 24-hour evaluation, both group of seeds had higher moisture content when matriconditioned at 25°C. The quality of corn seeds was affected by matriconditioning and the higher imbibition temperatures provided the expression of greater vigor in corn seedlings, being useful for this specie.

Enzyme activity in the micropylar region of Melanoxylon brauna Schott seeds during germination under heat stress conditions

Abstract: Recent studies indicate that global temperatures will rise substantially in the 21st century, leading to the extinction of several plant species, as plant metabolism and germination are greatly affected by temperature. Melanoxylon brauna, a tree species native to the Atlantic Forest that occurs from northeastern to southeastern Brazil, is one of the many species threatened by global warming. Despite the economic and ecological importance of M. brauna, studies investigating the influence of heat stress on seed germination and biochemical responses are still incipient. This study aimed to evaluate enzyme activity in the micropylar region of M. brauna seeds during germination under heat stress conditions. Endo-β-mannanase, α-galactosidase, polygalacturonase, pectin methylesterase, pectin lyase, total cellulase, 1,3-β-glucosidase, and 1,4-β-glucosidase activities were determined in micropyles of seeds imbibed for 24, 48 and 72 h at 25, 35 and 45 °C. Seed germination was highest at 25 °C. Endo-β-mannanase activity was not detected under any of the experimental conditions, but imbibition temperature had a significant effect on the activity of all other enzymes.

Adjustments in the tetrazolium test methodology for assessing the physiological quality of chickpea seeds

Abstract: Quick tests are essential tools to evaluate seed quality. The objective of this study was to adapt the methodology of tetrazolium test, by identifying the most suitable pre-conditioning parameters of imbibition temperature and duration, and tetrazolium solution concentrations, in order to assess the physiological quality of chickpea seeds. Also, this work proposed the separation of lots in classes, according to the viability and vigor of the seeds. Three lots of chickpeas (lot 1 - BRS Aleppo C1, lot 2 - BRS Aleppo basic, and lot 3 - Cicero) were evaluated. They were analyzed according to three combinations of imbibition temperature and duration (41 °C for 4 hours, 41 ºC for 6 hours, and 30 ºC for 18 hours) and two tetrazolium concentrations (0.1% and 0.5%). The imbibition at 41 °C for 4 or 6 hours, and at 30 ºC for 18 hours allowed clear visualization of injuries in the seeds after immersion in 0.1% tetrazolium solution. The intense coloration formed by the 0.5% solution of this salt prevented the differentiation of the types of damage. In addition, it was possible to separate the seeds into four classes: class I (viable and vigorous, without damages), class II (viable and vigorous, with superficial injuries), class III (viable and non-vigorous), and class IV (non-viable).

Freezing tolerance in hydrated lettuce (Lactuca sativa) seeds is dependent on cooling rate but not imbibition temperature

The effect of cold acclimation and cooling rate conferring viability of fully hydrated Lactuca sativa cv. Iceberg seeds were studied using differential scanning calorimetry (DSC) and controlled freezing experiments, with an intention to gain insights into the mechanisms seeds use in the natural environment to survive low temperatures. Rapidly cooled (60 °C h−1) cold acclimated or non-acclimated seeds although showed a high-temperature exotherm (HTE) and a low-temperature exotherm (LTE), the mortality correlated only with the LTE noted predominantly around −16 °C and below which no seed survived. In contrast, cooling cold acclimated and non-acclimated seeds at a slower rate (3 °C h−1), generated only one exotherm above −13 °C and seed viability was unaffected below this exotherm. However, noticeable seed mortality occurred in slow-cooled seeds during decrease in temperature and at below −40 °C no seeds survived, indicating that there is a lower limit to this mechanism. Excessive desiccation of the embryo water and/or membrane damage is proposed to be a likely factor contributing to seed mortality at lower temperatures. We conclude that cold acclimation is neither an essential nor a satisfying requirement for low-temperature survival of L. sativa seeds. The mechanism is rather determined by the rate at which the seeds are cooled.

Kinetics of solute leachate from imbibing Caesalpinia echinata Lam. (Brazilwood) seeds

The electrical conductivity of leachates from imbibing seeds has been used as a vigor test for several species. The adaptation of this methodology to different species requires knowledge on the leaching kinetics of electrolytes. For Brazilwood seeds, the classic method was not satisfactory and rapid tests are essential because they have low storage capacity at room temperature. Leaching kinetics during seed imbibition is a function of physiological quality, presence or absence of seed coat, imbibing temperature and the initial moisture content of seed. In this study, the electrolyte leaching rate of six different categories of seeds, from two regions, was evaluated in seeds with and without seed coat and incubated with different moisture contents and at different temperatures. The results showed that the electrolyte leaching rate in Brazilwood seeds is independent of the physiological quality, the presence or absence of seed coat and imbibition temperature, but these factors changed the total amount of electrolytes leached. The leaching rate increased in the first few minutes of imbibition, suggesting that the adjustment of the methodology must consider the reduction in imbibition time, reduction in temperature, use of a controlled and slower pre-imbibition, and replacement of the imbibition solution after the first few minutes.

Test of electric conductivity on the assessment of physiological quality of crambe seeds

The study aimed to assess present the effects of water volume and imbibition periods on the application of electric conductivity test on crambe seeds. We used crambe (Crambe abyssinica Hochst) seeds of 5 lots, FMS Brilhante cultivar, provided by the MS Foundation, from properties located in different locations of Mato Grosso do Sul State, produced on the 2012 harvest. We used randomized block designs with four replicates. For the characterization of the lots, we conducted germination tests and emergence speed index. Posteriorly, we performed the electric conductivity test, using 25oC as imbibition temperature, four volumes of water (20mL, 30mL, 40mL and 50mL) and 5 imbibition periods (30, 60, 120, 240 e 360 minutes). We observed that the higher the volume the lower the quantity of electrolytes liberated by the seeds. The electric conductivity test was efficient in order to assess the vigor of crambe seeds. The volumes of 20 and 30mL, with imbibition period of 240 minutes, were the most favorable conditions in the conduction of our test.

English

Germination is a key event in plant life cycle and imbibition temperature is an important factor for the major reorganization pro- cesses in the germinating seeds. Sub-physiological temperature at this stage affects virtually all aspects of cellular function including protein folding, kinetic parameters of membrane fluidity, protein assembly, and general metabolic processes. In this article we will review the re- search which has been carried out to decipher the basic mechanisms of low temperature (LT) stress with special emphasis on germination. With the better understanding of LT tolerance in some plant species we will also discuss how these attributes can be transferred in the im- portant food crops to attain better germination stamina at sub-physiological temperatures. At germination stage, the cellular machinery in the embryo is not at its proper place and is going through reorganisation and any environmental severity has devastating effects on the fragile plant. But LT resistant species have evolved the ability to acclimatise, with the remodelling of cell and tissue structures and the reprogram- ming of metabolism and gene expression. Metabolic networks are redirected towards the synthesis of cryoprotectant molecules, which in association with other proteins bring about physical and biochemical restructuring of cell membranes through changes in the lipid composi- tion and induction of other non-enzymatic proteins that alter the freezing point of water. Genetic engineering of crops for enhanced seed germination performance will certainly help to achieve optimum agricultural yields..

Viability of recently harvested and stored Xylopia aromatica (Lam.) Mart. (Annonaceae) seeds

Xylopia aromatica is a native species from Brazil's "Cerrado", recommended for restoration ecology and also as a medicine. Its seeds have embryos with morphophysiological dormancy, making nursery propagation difficult. The objective of this study was to verify the efficiency of X-ray and tetrazolium tests for evaluating the viability of three seed lots, stored for different periods. All seeds were X-rayed (13 kV, 350 seconds) and samples used for tetrazolium and germination tests. In the tetrazolium test, seeds were submitted to six treatments at two temperatures (25 and 30 °C) with imbibition in distilled water and immersion in three concentrations of tetrazolium solution (0.5, 0.75 and 1%) at the two imbibition temperatures. Seeds for the germination test were placed for imbibition in distilled water and a 500 ppm Promalin® (6-Benzyladenine + GA4 + GA7) solution and later sown in sterilized sand. The embryo could not be observed with the X-ray test. However, those seeds observed with an undamaged endosperm did not differ in the percentages of seeds with firm and stained endosperms observed in the tetrazolium test for all the lots. The tetrazolium test is efficient for evaluating seed viability, principally if imbibed at 30 °C and immersed in a 0.5% solution at 30 °C.

A gene encoding an abscisic acid biosynthetic enzyme (LsNCED4) collocates with the high temperature germination locus Htg6.1 in lettuce (Lactuca sp.).

Thermoinhibition, or failure of seeds to germinate when imbibed at warm temperatures, can be a significant problem in lettuce (Lactuca sativa L.) production. The reliability of stand establishment would be improved by increasing the ability of lettuce seeds to germinate at high temperatures. Genes encoding germination- or dormancy-related proteins were mapped in a recombinant inbred line population derived from a cross between L. sativa cv. Salinas and L. serriola accession UC96US23. This revealed several candidate genes that are located in the genomic regions containing quantitative trait loci (QTLs) associated with temperature and light requirements for germination. In particular, LsNCED4, a temperature-regulated gene in the biosynthetic pathway for abscisic acid (ABA), a germination inhibitor, mapped to the center of a previously detected QTL for high temperature germination (Htg6.1) from UC96US23. Three sets of sister BC3S2 near-isogenic lines (NILs) that were homozygous for the UC96US23 allele of LsNCED4 at Htg6.1 were developed by backcrossing to cv. Salinas and marker-assisted selection followed by selfing. The maximum temperature for germination of NIL seed lots with the UC96US23 allele at LsNCED4 was increased by 2–3°C when compared with sister NIL seed lots lacking the introgression. In addition, the expression of LsNCED4 was two- to threefold lower in the former NIL lines as compared to expression in the latter. Together, these data strongly implicate LsNCED4 as the candidate gene responsible for the Htg6.1 phenotype and indicate that decreased ABA biosynthesis at high imbibition temperatures is a major factor responsible for the increased germination thermotolerance of UC96US23 seeds.Electronic supplementary materialThe online version of this article (doi:10.1007/s00122-010-1425-3) contains supplementary material, which is available to authorized users.

Freezing and desiccation tolerance of imbibed canola seed

Depending on the environmental conditions, imbibed seeds survive subzero temperatures either by supercooling or by tolerating freezing‐induced desiccation. We investigated what the predominant survival mechanism is in freezing canola (Brassica napus cv. Quest) and concluded that it depends on the cooling rate. Seeds cooled at 3°C h−1 or faster supercooled, whereas seeds cooled over a 4‐day period to −12°C and then cooled at 3°C h−1 to−40°C did not display low temperature exotherms. Both differential thermal analysis and nuclear magnetic resonance (NMR) spectroscopy confirmed that imbibed canola seeds undergo freezing‐induced desiccation at slow cooling rates. The freezing tolerance of imbibed canola seed (LT50) was determined by slowly cooling to −12°C for 48 h, followed with cooling at 3°C h−1 to −40°C, or by holding at a constant −6°C (LD50). For both tests, the loss in freezing tolerance of imbibed seeds was a function of time and temperature of imbibition. Freezing tolerance was rapidly lost after radicle emergence. Seeds imbibed in 100 μM abscisic acid (ABA), particularly at 2°C, lost freezing tolerance at a slower rate compared with water‐imbibed seeds. Seeds imbibed in water either at 23°C for 16 h, or 8°C for 6 days, or 2°C for 6 days were not germinable after storage at −6°C for 10 days. Seeds imbibed in ABA at 23°C for 24 h, or 8°C for 8 days, or 2°C for 15 days were highly germinable after 40 days at a constant −6°C. Desiccation injury induced at a high temperature (60°C), as with injury induced by freezing, was found to be a function of imbibition temperature and time.

Teste de condutividade elétrica em sementes de amendoim

O teste de condutividade elétrica (CE) tem potencial para ser empregado no controle de qualidade pelas empresas produtoras de sementes, no entanto há fatores que podem afetar os resultados obtidos. Neste sentido, o trabalho teve como objetivo estudar os efeitos do tamanho da semente, do número de sementes da amostra e do período e temperatura de embebição que podem influenciar a interpretação dos resultados do teste de CE, em sementes de amendoim. Utilizou-se o delineamento experimental inteiramente casualizado em esquema fatorial 3 x 3: três lotes de semente, classificados em três tamanhos (peneiras 18, 20 e 22). Avaliou-se a CE em dez tempos de embebição (3, 6, 9, 12, 15, 18, 21, 24, 27 e 30 horas). O trabalho foi composto de quatro ensaios, onde se combinou número de sementes e temperatura de exposição das mesmas à embebição: a) quatro repetições de 25 sementes a 20ºC; b) quatro repetições de 50 sementes a 20ºC; c) quatro repetições de 25 sementes a 25ºC; d) quatro repetições de 50 sementes a 25ºC. A leitura da CE foi realizada por condutivímetro e os resultados expressos em µS.cm-1.g-1. O tamanho da semente afetou os resultados da CE; o tempo de embebição pode ser reduzido para até 3 horas; a temperatura de embebição de 25ºC mostrou-se mais promissora do que 20ºC, assim como a utilização de 50 sementes puras.

Ageing increases the sensitivity of neem (Azadirachta indica) seeds to imbibitional stress

Imbibitional stress was imposed on neem (Azadirachta indica) seeds by letting them soak for 1 h in water at unfavourable, low temperatures before further incubation at 30°C. Sensitivity to low imbibition temperatures increased with a decrease in seed moisture content (MC). To investigate a possible involvement of seed age in the extent of imbibitional damage, initially high-quality seed lots that differed in storage history (10 weeks versus 10 months) were examined at 4 and 7% MC (fresh weight basis). After 10 months of storage, the 7% MC seeds had become sensitive to imbibitional stress. Further drying (1 week) to 4% MC affected aged seeds more than non-aged seeds. Barrier properties of cellular membranes in axes excised after 1 d of rehydration were estimated using a spin-probe technique. The proportion of cells with intact membranes increased with increasing imbibition temperature. For each temperature tested, there were more cells with leaky membranes after 10 months than after 10 weeks of dry storage. Localization of embryo cells displaying loss of turgor and abnormal cellular structure was accomplished using cryo-planing, followed by cryo-scanning electron microscopy. Inspection of the cryo-planed surfaces confirmed that imbibitional damage was temperature dependent, occurring at the periphery. Ageing increased the number of imbibitionally damaged, peripheral cell layers. Germination was estimated to fail when less than 70% of axis cells were alive. We conclude that ageing increases the sensitivity to imbibitional stress. Both the fast ageing and the sensitivity to imbibitional stress might explain the apparent controversies about neem seed desiccation tolerance and storage behaviour.

The Effect of Exposure to Ascending/Descending Imbibition Temperatures in Saline Solutions on Shoot and Root Growth Allocation in Germinating Sorghum Seed

AbstractSorghum (Sorghum bicolor L. Moench) seeds were examined to determine the influence of exposure to ascending and descending imbibition temperature regimes on plumule and radicle axes behaviour of seed after treatment. Treatments included soaking in distilled water, 4.5 % NaCl or 4.5 % KCl for 3 days at three ascending or descending temperatures ranging from 11 to 21 °C. Root growth was enhanced by descending temperatures (21, 16 and 11 °C) over the 3‐day period, whereas ascending temperatures (11, 16 and 21 °C) increased growth differences between shoots and roots. Shoot–root growth was affected by imbibition temperature to a greater extent than germination. However, seed soaking treatments in NaCl or KCl did not improve root or shoot growth, but did improve germination rates.

Imbibition Temperature Affects on Seedling Vigor: In Crops and Shrubs

Imbibition at cold temperatures reduces seedling vigor of some species, but is beneficial to others. We used 3 rangeland shrubs and 8 agronomic crop species to test for a general relationship between imbibition temperature (5 to 30°C) and seedling vigor measured as post-germination growth; and to test for an effect of imbibition temperature on seed water uptake and dry weight loss during imbibition. Imbibition temperatures between 5 and 15°C were correlated with greater seedling length of the shrubs while most crops were favored by imbibition temperatures between 20 and 30°C. Winter wheat (Triticum aestivum L.) response to imbibition temperature was similar to that of the shrubs. Generally, shrubs had lower post-germination growth than crops, and during imbibition most crop seeds lost less weight than shrub seeds. Winter wheat had high weight loss as well as high seedling vigor. Seed water content generally increased with increasing imbibition temperature; however, winter wheat, kochia (Kochia prostrata (L.) Schrad.), and big sagebrush (Artemisia tridentata Nutt.) had significantly less water when imbibed at 30°C than when imbibed at lower temperatures. The differences due to temperature suggest the relationship between imbibition temperature and seedling vigor is a general phenomenon related to the physiology of water uptake and to seed respiration (as indicated by weight loss). Therefore, we recommend that optimum imbibition temperatures be defined by species and incorporated into seed-testing guidelines. This appears particularly important for species that do not have a long history of cultivation and whose response to temperature may differ significantly from that of crops.

Imbibition temperatures affect bitterbrush seed dormancy and seedling vigor

Bitterbrush first-year seedling survival is low. To determine whether imbibition temperatures affected seedling vigor, I compared post-imbibition seed weight, germination, and early growth among untreated, thiourea-treated, and cool-moist-treated seeds from three collections. Seedling axial lengths from untreated seeds averaged 28 mm among all imbibition temperatures. This compared to 31 mm from thiourea-treated seeds, 68 mm from seed held at 5°C for 14 days, and 118 mm from seeds held at 2°C for 28 days. There was no imbibition temperature for untreated or thiourea-treated seeds that compensated for the lack of a cool-moist treatment. Seed treatments or seedbed conditions which fully remove dormancy and reduce dormant-seed respiration appear likely to increase seedling survival during the first growing season.

Imbibition Temperature Affects Winterfat (Eurotia Lanata (Pursh) Moq.) Seed Hydration and Cold-Hardiness Response

Winterfat (Eurotia lanata (Pursh) Moq.) diaspores harvested from 1 Canadian and 2 USA sites were imbibed at 0, 5, 10, and 20 degrees C. It was hypothesized that imbibition temperature affects seed hydration which is related to cold-hardiness of winterfat. Weight gain was measured at 8-hour intervals until full hydration, and embryo water content was determined. Water content of fully hydrated seeds differed among collections and lower imbibition temperatures were always associated with greater seed water content. Differences in water content of seeds imbibed at different temperatures was related to cold-hardiness. When water content of embryos was measured, differences among imbibition temperatures existed, but were reduced. Differences in seed water content among imbibition temperatures were mainly due to endosperm other than the embryo because the embryo hydrated faster than other seed parts. Suggestions were made for modeling seed water relations based on this study.

Evidence of Cell Deterioration in Winterfat Seeds during Refrigerated Storage

Effective storage of wildland seeds helps alleviate supply shortages and mitigates variable production associated with annual weather patterns. The storage environment is critical for seeds like winterfat [Eurotia lanata (Pursh) Moq.] that rapidly lose viability under ambient conditions. Defining seed response to storage conditions is basic to effective seed storage programs. We used electron micrographs of freshly collected, and of stored winterfat seeds, with vigor tests to compare seedling vigor and to relate seed performance to seed cell biology as influence by; (a) seed age under known storage conditions, and (b) imbibition temperatures. We found that imbibition temperatures had little influence on the vigor of fresh seeds but significantly influenced aged seeds. Mitochondrial deterioration was evident in winterfat seeds stored 5-6 years at 5 degrees C, and in fresh, but incompletely hydrated seeds held at 20 degrees C. We recommend seeds be held at -18 degrees C or colder for long-term storage and that field seedings be done during the cold season to reduce the chance that incompletely hydrated seeds will be exposed to warm temperatures.