Laboratory Freezing Research Articles

Dormancy dynamics and cold hardiness of apple trees grown in a mild winter region

In temperate fruit plants, climate is the main factor correlating changes in plant physiology, mainly those related to entry and exit from dormancy and cold hardiness. Acclimation to cold and its relationship with dormancy are still unknown in areas with a subtropical climate. Therefore, this study aimed to investigate the dormancy dynamics and their interaction with the cold hardiness of different tissues of apple cultivars with different chilling requirements in two cultivation sites in a mild winter region in southern Brazil. The analyses were conducted from 2018 to 2022. The cultivars Gala, Fuji, and Eva were used in two environments with different altitudes. The dormancy dynamics were analyzed using the single-node cutting test, and the cold hardiness of the different tissues of each genotype was evaluated through electrolyte leakage in laboratory freezing tests. Cultivars Gala and Fuji had a greater depth of dormancy than Eva. Plants grown in orchards with higher chill accumulation had a greater depth of dormancy. Cold hardiness varied among cultivars, with the Eva cultivar having the lowest cold hardiness in mid-winter. The tissues (bud, bark, and wood) had different cold hardiness in early winter, with wood having the greatest cold hardiness, followed by bud and bark. As Eva did not go into deep dormancy, a superficial and short acclimation to cold was observed, in addition to rapid sprouting, even in winter. This condition predisposed it to cold damage to tissues in the pre-sprouting period. In this study, we found that maximum cold hardiness occurred after the end of the deep-endodormancy phase. Deacclimation of all cultivars occurred very quickly.

Winter hardiness of apple clonal rootstocks in Southern Cisbaikalia

The paper presents the results of a study of apple clonal rootstocks carried out in 2017-2022 in the trial plots located in the Irkutsk region. The objects of the study were clonal rootstocks from various scientific institutions. The conducted fieldwork allows us to state that the ecological conditions of the Southern Cisbaikalia are generally favorable for the use of clonal rootstocks in the regional horticulture. It was found that the most adaptive forms of all the studied clonal rootstocks are the rootstocks of the Ural selection (Ural and Ural 2) and the rootstock of the Estonian selection (E-56). The clonal rootstocks 70-6-8, Arm18, and K-2 withstood winter worst of all. According to the fieldwork results, the rest of the rootstocks showed medium winter hardiness. As a result of laboratory freezing experiments, E-56 high winter hardiness was confirmed. The study of cultivar-rootstock combinations showed good compatibility of clonal rootstocks with semi-cultivated apple trees. The variety and type of the rootstock were statistically proven to affect the degree of temperature damage to fruit trees. The clonal rootstocks with high winter hardiness and those with medium winter hardiness and high recovery ability were selected for further breeding work.

Determination of frost resistance of sweet cherry varieties using laboratory freezing

Determination of frost resistance of sweet cherry varieties using laboratory freezing

Partitioning of Dissolved Organic Carbon, Major Elements, and Trace Metals during Laboratory Freezing of Organic Leachates from Permafrost Peatlands

Climate change is likely to modify the freezing–thawing cycles in soils and surface waters of permafrost-affected and subarctic regions. However, the change of solution chemical composition during ice formation and the evolution of the remaining fluids remain very poorly known. Towards a better understanding of dissolved (<0.45 µm) organic carbon, as well as major and trace element behavior in permafrost peatland environments, here we performed laboratory freezing of peat leachates, from complete freezing to complete thawing, in order to quantify the partitioning of solutes between the aqueous solution and the remaining ice. Freezing experiments were conducted, with and without polyurethane insulation. Two main types of experiments involved (i) progressive freezing, when we started from liquid leachates (filtered <0.45 µm) and allowed them to freeze at −18 °C, and (ii) progressive thawing, where first, we froze solid a series of <0.45 µm filtered leachates and then monitored their thawing at room temperature, 20 °C. We hypothesized the existence of two main groups of solutes, behaving conservatively or non-conservatively during freezing, depending on their incorporation into the ice or their ability to coagulate in the form of insoluble minerals or amorphous materials in the fluid phase. An unexpected result of this work was that, despite a sizable degree of element concentration in the remaining fluid and possible coagulation of organic, organo-mineral, and inorganic compounds, the freezing and subsequent thawing produced final concentrations of most solutes which were not drastically different from the initial concentrations in the original leachates prior to freezing. This demonstrates the high stability of dissolved (<0.45 µm) organic carbon, iron, aluminum, and some trace metals to the repetitive freezing and thawing of surface waters in permafrost peatlands.

Use of screw pile foundations to reduce temperature of warming permafrost: Lab tests and numerical modeling

Steel screw piles may be a viable pile foundation type in the permafrost region of the Canadian Arctic but the effects of climate change may accelerate the creep settlement rate of the pile. Reducing the temperature around a pile is an effective way of enhancing the long-term performance of a pile. This study proposes a technique that combines the steel screw pile with the artificial ground freezing method, where liquid coolant is circulated through the hollow screw pile shaft to lower the temperature of surrounding permafrost. A series of laboratory experiments of freezing tests was conducted to verify the feasibility of the proposed technique. A finite element model was then developed to evaluate the cooling effect of this technique by analysing the duration of the permafrost freezing and the power of removing the heat from the soil. The numerical model was calibrated against laboratory freezing tests. A series of numerical analyses were performed to investigate the effects of soil properties and screw pile shaft configuration on the ground freezing process in field application. The duration required for freezing the soil at a radial distance of 450 mm to −2 °C was estimated and compared. The results showed that the proposed method was applicable in the field. Numerical results showed that the power of removing the heat from the soil was larger when using the screw segment than the smooth segment. The results are expected to guide the field application of artificial ground freezing around screw piles installed in permafrost.

Морозостійкість великоплідних сортів черешні (Cerasus avium Moench.) в умовах правобережної частини Західного Лісостепу

The results of determining the potential level of frost resistance of 27 promising large-fruited cherry varieties using the laboratory freezing method are presented. The purpose of the research was to study the adaptive potential of promising large-fruited cherry varieties of Ukrainian breading program in terms of determining their resistance to the impact of critical low temperatures. The degree of tissues frost damage of shoots and buds was assessed according to intensity of their browning on transverse anatomical sections based on microscopic analysis on a six-point scale. According to the results of research, varieties with the highest level of frost resistance were selected. Laboratory freezing of one-year branches of large-fruited cherries varieties during a period of relative rest under the temperatures of -25 and -30 °С, should the features of freezing of their tissues and parts of growths. A higher degree of freezing of the tops of one-year branches compared to their middle part was established. It also was revealed a high potential frost resistance of the researched varieties at temperatures of minus 25 °С. At the same time, at – 30 °С, severe damage of individual tissues of one-year branches was found in the varieties Dzherelo, Regina, Prostir, Vasylisa Prekrasna and Temporion, which were marked by a high indexed score of damage - 61.8-72.3 % (for the minimum permissible 50 %). Against their background, the most frost-resistant varieties were selected, such as Donchanka, Anons, Kazka, Etyka, Krupnoplidna, Valeriia and Anshlag, which had the lowest indexed damage score (30.4-43.8 %) and may be promising for growing in the right bank part of the west Lisosteppe of Ukraine, because they were characterized by a greater adaptability to the impact of low critical temperatures during a period of relative rest. Key words: cherry, cultivar, laboratory freezing, temperature, critical tissue damage, frost resistance.

The basis of cell cryopreservation

Cryopreservation (banking) techniques have been known to nature for centuries. Many species of insects, amphibians, fish and even reptiles use natural cryopreservation methods to survive the harsh conditions of winter or to live in extremely cold temperatures. Cryopreservation and dreams of immortality have intrigued humanity for years. The first reports of observing the effects of freezing sperm (stored in snow) date back to 1776. In 1866, Montegazza was the first to suggest a vision completely unimaginable for the time: "a man dying on the battlefield can conceive an heir from sperm frozen and stored at home". The first, at that time still unsuccessful, reports of laboratory freezing of human sperm date back to the 1930s [1]. Finally, mankind "learned" cryopreservation in the middle of the twentieth century, when on October 15, 1949, the article "Revival of spermatozoa after vitrification and dehydration at low temperatures" appeared in print in the Nature journal, summarising the pioneering research of scientists from the National Institute for Medical Research, Mill Hill, London [2]. This concerned the freezing of fowl sperm in the presence of glycerol, ethylene glycol and propylene glycol in such a way that after thawing it was able to fertilise eggs effectively. The subsequent use of dimethyl sulfoxide (DMSO) revolutionised modern cryobiology [3-5]. Thus began the era of cryopreservation, without which today it is difficult to imagine the work of cell biology laboratories, modern animal breeding, or the development of modern medicine.

A finite volume-based model for the hydrothermal behavior of soil under freeze-thaw cycles.

Freeze–thaw cycles in soil are driven by water migration, phase transitions, and heat transfer, which themselves are closely coupled variables in the natural environment. To simulate this complex periglacial process at different time and length scales, a multi-physics model was established by solving sets of equations describing fluid flow and heat transfer, and a dynamic equilibrium equation for phase changes in moisture. This model considers the effects of water–ice phase changes on the hydraulic and thermal properties of soil and the effect of latent heat during phase transition. These equations were then discretized by using the finite volume method and solved using iteration. The open-source software OpenFOAM was used to generate computational code for simulation of coupled heat and fluid transport during freezing and thawing of soil. A set of laboratory freezing tests considering two thermal boundary conditions were carried out, of which the results were obtained to verify the proposed model. In general, the numerical solutions agree well with the measured data. A railway embankment problem, incorporating soil hydrothermal behavior in response to seasonal variations in surface temperature, was finally solved with the finite volume-based approach, indicating the algorithm’s robustness and flexibility.

Зимостійкість та перспективи використання рослин-інтродуцентів Rodgersia aesculifolia Batalin в умовах міста Києва

Зимостійкість та перспективи використання рослин-інтродуцентів Rodgersia aesculifolia Batalin в умовах міста Києва

Cold hardiness of peach flowers at different phenological stages

At the colder peach production regions it is important to know the cold hardiness of peach cultivars at different phenological stages of flowering. In our experiment, artificial freezing tests were conducted in a climate chamber in five selected years between the period of 2007 and 2016 to determine the freeze tolerance of generative organs of three peach cultivars (‘Venus’, ‘Redhaven’, ‘Piroska’) at different phenological stages of bloom. Based on the results of the laboratory freezing tests LT<sub>50</sub> values were calculated. Our results showed that LT<sub>50</sub> values of examined peach cultivars in swelled bud stage averaged over five years were between –6.8 and –11.2°C according to cultivar, and as phenological phases progressed, cold hardiness of generative organs decreased. At the end of bloom LT<sub>50</sub> values varied between –1.7 and –4.1°C. Cultivar ‘Piroska’ had the highest freeze tolerance and cultivar ‘Venus’ showed the lowest in each year studied. This study shows that trees with delayed development are more prone to cold damage to flowers.

Cold hardiness of peach flowers at different phenological stages

At the colder peach production regions it is important to know the cold hardiness of peach cultivars at different phenological stages of flowering. In our experiment, artificial freezing tests were conducted in a climate chamber in five selected years between the period of 2007 and 2016 to determine the freeze tolerance of generative organs of three peach cultivars (‘Venus’, ‘Redhaven’, ‘Piroska’) at different phenological stages of bloom. Based on the results of the laboratory freezing tests LT<sub>50</sub> values were calculated. Our results showed that LT<sub>50</sub> values of examined peach cultivars in swelled bud stage averaged over five years were between –6.8 and –11.2°C according to cultivar, and as phenological phases progressed, cold hardiness of generative organs decreased. At the end of bloom LT<sub>50</sub> values varied between –1.7 and –4.1°C. Cultivar ‘Piroska’ had the highest freeze tolerance and cultivar ‘Venus’ showed the lowest in each year studied. This study shows that trees with delayed development are more prone to cold damage to flowers.

THE WINTER-HARDINESS OF THE VARIETIES AND FORMS OF FILBERT (CORYLUS DOMESTICA KOSENKO ET OPALKO), PLANTED IN UKRAINE

The results of the study of winter-hardiness of the varieties and forms of filbert (Сorylus domestica Кosenko еt Оpalko), planted in Ukraine, are presented. The aim was to determine the suitableness of filbert plants for industrial planting in the gardening zone of Ukraine that needed the most exact assessment of potential of their winter and frost resistance. For attaining this aim we introduced in the research the laboratory freezing of tissues and organs of prospective varieties of filbert with modeling of influence of the low negative temperatures at the level - 25, - 30 and - 35 °С. As the material of research were used the filbert plants of varieties and forms, prospective for planting in Ukrainian conditions. The study and procurement of slip material was carried out in parent filbert plants of decennial age of research-productive district of the National dendrologic part “Sofiivka”, NAS of Ukraine during 2015–2016 according to conventional methods and recommendations. Incomplete coincidence of the data of frost resistance of studied filbert variants in the natural conditions and at the different modes of direct freezing can be explained by the varietal features. Despite the unfavorable conditions of wintering 2015–2016, the freezing of studied filbert plants under the garden conditions was completely insufficient (summary point of damage was less 10) and insufficient (the level of disorder is limited by 11–20 points). Besides the ability to endure the short-term strong frosts, the high winter-hardiness is demonstrated only by filbert plants, less sensitive to the provoking influence of thaw. The complex assessment of the winter and frost resistance of filbert plants by the field and instrumental methods proved the sufficient adaptability of studied samples to the conditions of studied gardening zone. The varieties and forms of filbert Sofiiivsky-1 and especially Pavlenko’s gift were recognized as the best by the frost resistance and potential of winter-hardiness.

Морозостійкість рослин культиварів acer platanoides l. у насадженнях м. Києва з різним ступенем антропогенної трансформації

In order to develop recommendations for future using in urban plantings most hard cultivars of such species as Acer platanoides L. the grounded studies of their frost resistance in city ecotypes with different levels of transformation are important. The potential frost resistance of the specimens we determined by direct laboratory freezing of the annual shoots with subsequent analysis of tissue damages using an anatomical and microscopic evaluation in the Plant Physiology Laboratory of the Institute of Horticulture of the National Academy of Agrarian Sciences of Ukraine (IH NAAS). The objects of the research were plants of A. platanoides species and its 5 cultivars – A. p. 'Globosum', A. p. 'Crimson King', A. p. 'Drummondii', A. p. 'Schwedlerii' and A. p. 'Reitenbachii'. The samples of annual shoots of three ecological and phytocoenotic zones of Kyiv city – parks, public gardens and streets or squares were taken. It was established, that the such cultivars as A. p. 'Reitenbachii' and A. p. 'Schwedlerii' were characterized by the highest resistance to low temperatures in urban conditions, which ones can be recommended for wide use in various ecotypes of the city. All cultivars and species other than A. p. 'Schwedlerii' were characterized by a decrease of frost resistance in difficult urban conditions.

Poultry marketing controls – Inter-laboratory validation of a method to detect previously frozen chicken breasts by determination of HADH activity

EU poultry marketing legislation requires that poultry be marketed either as fresh (chilled) poultry or as frozen (or quick-frozen) poultry. It is not permitted to market poultry which has been previously frozen as if it were fresh. A robust analytical method that is capable of distinguishing between fresh and previously frozen poultry is therefore required for the enforcement of the legislation. A method to detect whether poultry and other meats have been previously frozen was developed and validated by an earlier collaborative study in 1997. The method is based on measuring the HADH activity of intracellular juice pressed from the test samples. The ratio of the HADH activity of sub-samples tested before and after laboratory freezing is compared to a reference cut-off limit, to determine whether the sample has previously been frozen. In a subsequent study in 2010, improvements were made to the analytical procedure and a revised cut-off limit for chicken of 0.5 was determined. The aim of the current study was to validate the improved analytical procedure and the revised cut-off value for chicken via a collaborative trial with 12 European NRLs and 12 UK OCLs. Each laboratory was asked to analyse 24 chicken breast samples and to use the results to determine their thermal history (chilled or previously frozen) according to the SOP provided. All samples were supplied as chilled blind samples. The results of the study showed inter-laboratory variation between the results obtained for chilled and for previously frozen chicken breasts, however despite this, almost all of the samples were correctly identified and reported in terms of their thermal history. Although some reduction in the analytical variability of the method would be beneficial, the results confirmed the suitability of the method and the revised cut-off limit of 0.5 for the official control of marketing of chicken breasts within the EU.

Importance of vapor flow in unsaturated freezing soil: a numerical study

The role of vapor flow in unsaturated freezing soils is unclear, and usually ignored when analyzing water migration. Indeed, vapor flow is seldom considered in geotechnical design. On the other hand, frost heave damages were recently observed in a cold and arid region in China, where the groundwater table is about 20m deep, and cannot be explained using the classical frost heave theory which focuses on the coupled flow of heat and liquid water. This paper presents a new approach for modeling moisture and heat movement in unsaturated freezing soils, in which the phase change of evaporation, condensation of vapor flow are taken into account. The method enables numerically stable solutions with energy and mass conservation. The performance of the proposed model was evaluated by a series of laboratory freezing experiments, which involve a 60cm long soil column subjected to different initial conditions and boundary temperatures. It is shown that the proposed model is capable of effectively simulating the freezing process of an unsaturated soil. The vapor flux is shown to be significant, especially at the end stage where the freezing process is stabilized. Parametric analysis was carried out to clarify the role of vapor in moisture migration. The results show that vapor flow apparently contributes to ice formation and generally accounts for more than 10% of total water flux. The percentage of vapor flux in total flux (vapor flux ratio) positively relates to temperature gradient and freezing depth, but negatively relates to initial water content. Relations between vapor flux ratio and hydraulic parameters are less clear.

Laboratory freezing desalination of seawater

Freeze desalination of samples of seawater from Umluj beach, Red Sea, in Saudi Arabia, was investigated by laboratory experiments using nondirect freezing. The influence of kinetic parameters including degree of crystallization, freezing–melting cycles, and gradual melting on the total dissolved solids (TDS) and salt rejection was examined. The melted ice water produced by partial crystallization of single-stage freezing has two times less salt concentration than the feed seawater (TDS, 40,916 mg/l). Continuous cycling of the freezing–melting process reduced the dissolved salts to 1.5% with TDS 610 mg/l, in the level of drinking water. The TDS of the melted ice decreased with gradual melting time and reached 693 mg/l after 6 h. The results indicated that the laboratory freezing desalination could decrease sea ice salinity from 4.1 to 0.06% without using chemical additives.

Immersion freezing of supermicron mineral dust particles: freezing results, testing different schemes for describing ice nucleation, and ice nucleation active site densities.

Ice nucleation on mineral dust particles is known to be an important process in the atmosphere. To accurately implement ice nucleation on mineral dust particles in atmospheric simulations, a suitable theory or scheme is desirable to describe laboratory freezing data in atmospheric models. In the following, we investigated ice nucleation by supermicron mineral dust particles [kaolinite and Arizona Test Dust (ATD)] in the immersion mode. The median freezing temperature for ATD was measured to be approximately -30°C compared with approximately -36 °C for kaolinite. The freezing results were then used to test four different schemes previously used to describe ice nucleation in atmospheric models. In terms of ability to fit the data (quantified by calculating the reduced chi-squared values), the following order was found for ATD (from best to worst): active site, pdf-α, deterministic, single-α. For kaolinite, the following order was found (from best to worst): active site, deterministic, pdf-α, single-α. The variation in the predicted median freezing temperature per decade change in the cooling rate for each of the schemes was also compared with experimental results from other studies. The deterministic model predicts the median freezing temperature to be independent of cooling rate, while experimental results show a weak dependence on cooling rate. The single-α, pdf-α, and active site schemes all agree with the experimental results within roughly a factor of 2. On the basis of our results and previous results where different schemes were tested, the active site scheme is recommended for describing the freezing of ATD and kaolinite particles. We also used our ice nucleation results to determine the ice nucleation active site (INAS) density for the supermicron dust particles tested. Using the data, we show that the INAS densities of supermicron kaolinite and ATD particles studied here are smaller than the INAS densities of submicron kaolinite and ATD particles previously reported in the literature.

An experimental study on the frost heave properties of coarse grained soils

We investigated the impact of fines content on frost heave and compaction in subgrade construction materials, in order to determine the optimum fines content of coarse-grained soils (CGS) required to achieve reduced frost susceptibility and efficient compaction simultaneously. We conducted laboratory freezing tests simulating thermal conditions in the field, and compared open and closed systems. We studied 47 samples with different fines content, dry density, overburden pressure, and water supply (open or closed) by compaction tests and frost heave tests. Among other significant effects observed, the freezing temperature decreased gradually with incremental increases in the percent content of fines. Fines content proved to be an important factor influencing the amount of frost heave of CGS. Overburden pressure restrained the amount of frost heave to some extent. The frost heave ratio of CGS samples increased first before reaching the peak value of dry density and then decreased. Overall, our results show that the optimum fines content at which the CGS could be compacted effectively with low frost heave susceptibility was 9%. We also conclude that in the field, it is imperative to employ waterproofing and drainage measures.

Frost Heaving Characteristics of Subgrade Soils Using Laboratory Freezing System

Frost Heaving Characteristics of Subgrade Soils Using Laboratory Freezing System

실내 동상시스템을 이용한 노상토의 동상민감성 평가

The Korean Peninsula is considered as a seasonal frozen area that is thawed in the spring and frozen in the winter. The influence of fines of the frost susceptibility of subgrade soils were established by laboratory freezing tests simulating closely the thermal conditions in the field. During the winter season, the climate is heavily influenced by the cold and dry continental high pressure. Because of siberian air mass, the temperature of January is on average. This chilly weather generate the frost heaving by freezing the moisture of soil and damage potential of the geotechnical structure. In the freezing soil, the ice lenses increase the freeze portion of soil by absorbing the ground water with capillary action. However, the capillary characteristics differ from the sort of soil on the state of freezing condition. In this study, ten soil samples are prepared. The basic physical property tests were performed by following the Korean Industrial Standard and the soil specimens were classified by the Unified Soil Classification System (USCS). These classified soils are used to perform the laboratory opened systems freezing test in order to determine the frost heaving characteristics of soils such as unfrozen water content, heaving amount, and freezing depth.