High Level Of Plasticity Research Articles

Provenances vs. microhabitat influence on field performance of Quercus robur seedlings

Provenance trials, as the subject of continuous analyses, provide empirical information about the plasticity of tree species. Changing climate and environmental conditions likely favor genotypes with high levels of plasticity. Finding the suitable provenance for the reintroduction of pedunculate oak to habitats that are threatened and where this species no longer exists provides important information for the targeted use of the available gene pool. The dominant ecological factors in the development of pedunculate oak forests are groundwater level and changes in the hydrological regime of habitats. In this study, we established nursery and field provenance trials to test two pedunculate oak seed provenances from different hydrological conditions to investigate the influence of seedlings' provenance and field microhabitat on growth parameters and survival. In the nursery trial, the height and ground level diameter were measured. After three years in the pilot object, the height and diameter were analyzed again, as well as the survival. To determine the microhabitat influence planting area was divided in two ways: three repetitions and two planting blocks. In this study, significant differences in analyzed growth parameters between the chosen provenances were obtained at the end of the first vegetation period. In later ontogenetic phases influence of the provenance is missing. As the difference between provenances disappears, the influence of microhabitat occurs (significant differences between repetition or planting blocks). After the second year of development, no significant difference was observed between the two provenances of different hydrological regimes, but there are significant differences between the microhabitats in the afforested area (established pilot object).

Ecological plasticity and stability of cabbage crop ptoductivity as affected by method of sowing

Purpose. To establish the peculiarities of the formation of ecological plasticity and productivity stability of winter cabbage crops as affected by the components of agricultural technology, specifically the width of the rows and the application rates of mineral fertilizers.
 Methods. The research was carried out in the years 2018–2021 in the Chernihiv region at the Nizhyn Agricultural Technical Institute of the National University of Life and Environmental Sciences of Ukraine). Conventional methods were used in the research. The field experiment design provided for the cultivation of typhoon variety ‘Orakam’ under different methods of sowing (width between rows of 15, 30 and 45 cm) and rates of mineral fertilizers (without fertilizers, N80P60K60 and N120P90K90). Parameters of ecological stability (b) and plasticity (W) of seed yield and energy yield from biomass were calculated according to the Eberhard-Russell method using the Mathcad Prime 3.1 software.
 Results. The lowest stability of both seed yield (0.55–0.79) and energy yield from biomass (0.55–0.81) was noted in the treatments without fertilizers, while with N80P60K60 and N120P90K90 it was almost twice as high (1.03–1.33 and 0.97–1.32, respectively). At the same time, within all three fertilization backgrounds, a clear tendency of decreasing crop productivity stability along with increasing row width was observed. In particular, the highest coefficient of stability of seed yield in the experiment (1.33) was obtained on the background of N80P60K60 at a row spacing of 15 cm, at the same time as the row spacing increased to 30 and 45 cm, it decreased to 1.19 and 1.05, respectively. As for the plasticity parameters of the productive indicators, they were approximately at the same level in all treatments.
 Conclusions. The best conditions for the formation of high seed yield and total energy yield from the biomass of typhoon variety ‘Orakam’ were provided at a row width of 15 and 30 cm and the application of mineral fertilizers N80P60K60 and N120P90K90. In this case, the formation of crop productivity demonstrated a high level of plasticity. In general, intensive cultivation conditions contributed to the full realization of the crop biological potential and effective utilization of fertilizers.

Anatomical structure interpretation of the effect of soil environment on fine root function.

Fine root anatomy plays an important role in understanding the relationship between fine root function and soil environment. However, in different soil environments, the variation of fine root anatomical structure in different root sequences is not well studied. We measured the soil conditions and anatomical structure characteristics (root diameter, cortical tissue, vascular tissue and xylem) of fine roots of Cupressus funebris in four experimental sites, and analyzed each level of fine roots separately. We link these data to understand the relationship between fine root anatomy and soil conditions. We found that the anatomical structure of fine roots is closely related to soil environmental factors. The fine roots of lower root order are mainly affected by soil nutrients. Among them, the cortical tissue of first-order fine roots was positively correlated with potassium and phosphorus, but negatively correlated with nitrogen, while second- and third-order fine roots was positively correlated with soil total potassium and negatively correlated with nitrogen and phosphorus. For the fine roots of high root order, the cortical tissue disappeared, and the secondary vascular tissue was mainly affected by soil moisture. In addition, we also found that the division of fine root functional groups is not fixed. On the one hand, the function of third-order fine roots will slip. For example, the decrease of soil moisture will promote the transformation of third-order fine roots into transport roots, and the reduction of nitrogen will promote the transformation of third-order fine roots into absorption roots to fix nitrogen. This transformation strategy can effectively prevent the restriction of soil nutrients on plant growth. On the other hand, with the change of habitat, the first- and second-order fine roots are still the absorbing root, and the fourth- and fifth-order fine roots are still the transport root, but the efficiency of absorption and transport will be affected. In conclusion, our findings emphasize the fine roots in different soil environment to show high levels of plasticity, shows that fine root anatomical structure changes may make plants, and reveals that the fine is just order of reaction and its mechanism in the soil environment.

Population structure, regeneration potential and leaf morphological traits of Rhododendron campanulatum D.Don along an altitudinal gradient in Western Himalaya

The vegetation of the alpine treeline ecotone is among the most vulnerable and sensitive to global climate change. Treeline species respond to global warming through changes in their population structure, regeneration, plant functional traits and shift in their habitat. This study was carried out on Rhododendron campanulatum D.Don, a typical plant species of the Himalayan treeline ecotone, to understand the variation in population structure, regeneration potential and leaf morphological traits along the altitudinal gradient (3100–3550 m.a.s.l.) in Tungnath, Western Himalaya. We reported the higher seedling (3480 stem ha−1) and juvenile (2210 stem ha−1) density of the species above the treeline at 3400 m.a.s.l. This clearly shows a good regeneration status and indicates the upward shift of the species. Leaf morphological traits such as length, width, and the specific leaf area decreased with an increase in elevation but leaf thickness increased with an increase in elevation. SLA was higher (71.14 cm2/g; p < 0.001) at 3100 m.a.s.l. located below the treeline than 3550 m.a.s.l. (60.08 cm2/g; p < 0.001)) located above the treeline. The results indicate that the species has large flexibility in the morphological performance and its high level of plasticity in morphological traits may explain its wider niche and ability to survive in harsh alpine conditions.

Regional Patterning of Adult Neurogenesis in the Homing Pigeon's Brain.

In the avian brain, adult neurogenesis has been reported in the telencephalon of several species, but the functional significance of this trait is still ambiguous. Homing pigeons (Columba livia f.d.) are well-known for their navigational skills. Their brains are functionally adapted to homing with, e.g., larger hippocampi. So far, no comprehensive mapping of adult neuro- and gliogenesis or studies of different developmental neuronal stages in the telencephalon of homing pigeons exists, although comprehensive analyses in various species surely will result in a higher understanding of the functional significance of adult neurogenesis. Here, adult, free flying homing pigeons were treated with 5-bromo-deoxyuridine (BrdU) to label adult newborn cells. Brains were dissected and immunohistochemically processed with several markers (GFAP, Sox2, S100ß, Tbr2, DCX, Prox1, Ki67, NeuN, Calbindin, Calretinin) to study different stages of adult neurogenesis in a quantitative and qualitative way. Therefore, immature and adult newborn neurons and glial cells were analyzed along the anterior–posterior axis. The analysis proved the existence of different neuronal maturation stages and showed that immature cells, migrating neurons and adult newborn neurons and glia were widely and regionally unequally distributed. Double- and triple-labelling with developmental markers allowed a stage classification of adult neurogenesis in the pigeon brain (1: continuity of stem cells/proliferation, 2: fate specification, 3: differentiation/maturation, 4: integration). The most adult newborn neurons and glia were found in the intercalated hyperpallium (HI) and the hippocampal formation (HF). The highest numbers of immature (DCX+) cells were detected in the nidopallium (N). Generally, the number of newborn glial cells exceeded the number of newborn neurons. Individual structures (e.g., HI, N, and HF) showed further variations along the anterior–posterior axis. Our qualitative classification and the distribution of maturing cells in the forebrain support the idea that there is a functional specialization, respectively, that there is a link between brain-structure and function, species-specific requirements and adult neurogenesis. The high number of immature neurons also suggests a high level of plasticity, which points to the ability for rapid adaption to environmental changes through additive mechanisms. Furthermore, we discuss a possible influence of adult neurogenesis on spatial cognition.

Gene regulation in Escherichia coli is commonly selected for both high plasticity and low noise.

Bacteria often respond to dynamically changing environments by regulating gene expression. Despite this regulation being critically important for growth and survival, little is known about how selection shapes gene regulation in natural populations. To better understand the role natural selection plays in shaping bacterial gene regulation, here we compare differences in the regulatory behaviour of naturally segregating promoter variants from Escherichia coli (which have been subject to natural selection) to randomly mutated promoter variants (which have never been exposed to natural selection). We quantify gene expression phenotypes (expression level, plasticity and noise) for hundreds of promoter variants across multiple environments and show that segregating promoter variants are enriched for mutations with minimal effects on expression level. In many promoters, we infer that there is strong selection to maintain high levels of plasticity, and direct selection to decrease or increase cell-to-cell variability in expression. Taken together, these results expand our knowledge of how gene regulation is affected by natural selection and highlight the power of comparing naturally segregating polymorphisms to de novo random mutations to quantify the action of selection.

Children's Evolved Learning Abilities and Their Implications for Education.

In this article, I examine children’s evolved learning mechanisms that make humans the most educable of animals. These include (1) skeletal perceptual and cognitive mechanisms that get fleshed out over the course of development, mainly through play; (2) a high level of plasticity that is greatest early in life but that persists into adulthood; (3) remarkable social-learning capabilities; and (4) dispositions toward exploration and play. I next examine some evolutionary mismatches—conflicts between psychological mechanisms evolved in ancient environments and their utility in modern ones—specifically with respect to modern educational systems. I then suggest some ways educators can take advantage of children’s evolved learning abilities to minimize the effects of evolutionary mismatches, including (1) following developmentally appropriate practices (which are also evolutionarily appropriate practices), (2) increasing opportunities for physical activities, (3) increasing opportunities to learn through play, and (4) taking advantage of stress-adapted children’s “hidden talents.” I argue that evolutionary theory informs teachers and parents about how children evolved to learn and can result in more-enlightened teaching methods that will result in a more enjoyable and successful learning experiences for children.

Drug-Tolerant Persister Cells in Cancer Therapy Resistance.

One of the current stumbling blocks in our fight against cancer is the development of acquired resistance to therapy, which is attributable to approximately 90% of cancer-related deaths. Undercutting this process during treatment could significantly improve cancer management. In many cases, drug resistance is mediated by a drug-tolerant persister (DTP) cell subpopulation present in tumors, often referred to as persister cells. This review provides a summary of currently known persister cell subpopulations and approaches to target them. A specific DTP cell subpopulation with elevated levels of aldehyde dehydrogenase (ALDH) activity has stem cell-like characteristics and a high level of plasticity, enabling them to switch rapidly between high and low ALDH activity. Further studies are required to fully elucidate the functions of ALDH-high DTP cells, how they withstand drug concentrations that kill other cells, and how they rapidly adapt under levels of high cellular stress and eventually lead to more aggressive, recurrent, and drug-resistant cancer. Furthermore, this review addresses the processes used by the ALDH-high persister cell subpopulation to enable cancer progression, the ALDH isoforms important in these processes, interactions of ALDH-high DTPs with the tumor microenvironment, and approaches to therapeutically modulate this subpopulation in order to more effectively manage cancer.

The impact of collagen protein ingestion on musculoskeletal connective tissue remodeling: a narrative review.

Collagen is the central structural component of extracellular connective tissue, which provides elastic qualities to tissues. For skeletal muscle, extracellular connective tissue transmits contractile force to the tendons and bones. Connective tissue proteins are in a constant state of remodeling and have been shown to express a high level of plasticity. Dietary-protein ingestion increases muscle protein synthesis rates. High-quality, rapidly digestible proteins are generally considered the preferred protein source to maximally stimulate myofibrillar (contractile) protein synthesis rates. In contrast, recent evidence demonstrates that protein ingestion does not increase muscle connective tissue protein synthesis. The absence of an increase in muscle connective tissue protein synthesis after protein ingestion may be explained by insufficient provision of glycine and/or proline. Dietary collagen contains large amounts of glycine and proline and, therefore, has been proposed to provide the precursors required to facilitate connective tissue protein synthesis. This literature review provides a comprehensive evaluation of the current knowledge on the proposed benefits of dietary collagen consumption to stimulate connective tissue remodeling to improve health and functional performance.

Sexually-manifested variations in pigmentation of Boeckella poppei (Copepoda, Calanoida) from Livingston Island (Maritime Antarctica)

Antarctic environments are exposed to high levels of ultraviolet radiation (UVR) that are often detrimental to their biota. Recent studies suggest that the genus Boeckella (Copepoda, Calanoida) has a high level of plasticity in terms of its reaction to UVR, which enables its wide distribution in various water bodies in Antarctica. Boeckella poppei is common in freshwater habitats of all three main biogeographic regions in Antarctica: sub-Antarctic islands, maritime and continental. We present for the first time a specific photoprotective response in populations of B. poppei from Livingston Island, Maritime Antarctica. In non-ovigerous females and in males, we observed uniform distribution of carotenoids in the body, while these pigments were almost entirely concentrated in the ovisacs of mature females. We consider this as a means of progeny protection from the teratogenic influence of the high level of UVR in Antarctic environments. Unequivocally, such adaptation would facilitate the expansion of B. poppei on the continent through colonisation and survival in shallow freshwater habitats. Given that the Antarctic environment is dynamically changing over the past decades and the accelerated retreat of permanent ice cover is a premise for the formation of shallow ponds, B. poppei could be a suitable indicator for reflecting the ongoing global environmental changes in Antarctica.

Економно легована сталь для потреб гірничодобувної промисловості

It has been established that the downtime of ball mills due to the low durability of cast parts is 70...80 % of the total number of downtime, while material damage is estimated in hundreds of thousands of hryvnia. One of the weakest units of these mills are the discharge grids and scoops of the cochlear feeder, the durability of which reaches 5.5...6 months and 1.0...1.5 months, respectively, with the resource of operation of other parts of the mill 9...12 months. As a result of the analysis of the operating conditions of the gratings and scoops of the MSHR, it was found that the duration of operation and the mechanical properties of these parts depend mainly on the material from which they are made. Steel with a high level of plasticity and toughness (35GFL, 35HNL, 34HNML, etc.) had insufficient wear resistance due to low strength, hardness. Materials with a high level of hardness and strength (60Kh2SML) had a low impact toughness, which was the reason for emergency shutdowns of the mills as a result of breakdowns of parts. The analysis of the mechanical properties of ladles and gratings has established the required level of properties of these parts; σВ ≥ 850 MPa; НВ ≥ 2600 МPa; δ ≥ 8 %; Ψ ≥ 20 %, KCU ≥ 0,20 MJ/m2. The effect of changing the silicon concentration on the mechanical properties and wear resistance of steel containing 1.5% chromium and 0.40% manganese with different carbon contents has been studied. With an increase in the silicon content, the strength and hardness indicators increase. The effect of silicon on the plastic properties of steel, impact strength and wear resistance is nonlinear, with 0.9% manganese in this case, a monotonic decrease is observed not only in plastic properties and toughness, but also in wear resistance. This is explained by the fact that with an increase in the manganese content in steel, the segregation heterogeneity and stability of supercooled austenite increase, leading, after normalization, to the formation of a martensite-like structure. It is shown that in the production of castings operating under conditions of abrasive wear in combination with shock loads, it is advisable to observe the ratio of silicon to carbon 2.0...2.5. Mathematical planning of the experiment made it possible to obtain models that adequately describe the effect of the composition of steel on the level of its mechanical and operational properties. Based on the processing of the data obtained from the «STATISTICA» software package, a wear-resistant economically alloyed steel of the following composition was proposed: 0.45...0.50 % carbon; 1.7...2.0 % chromium; 0.5...0.7 % manganese; 1.2...1.5 % silicon. The use of such a composition of steel for the manufacture of unloading gratings and scoops of snail feeder allowed to increase their service life by 1.5 times by improving performance, and, consequently, reduce the maintenance cycle of ball mills, which increased economic efficiency. Keywords: ball grinding mill, alloy steel, mathematic modeling, structure, mechanical properties.

Effects of elevated temperature, reduced hydroperiod, and invasive bullfrog larvae on pacific chorus frog larvae.

Climate change and invasive species threaten many ecosystems, including surface freshwater systems. Increasing temperatures and reduced hydroperiod due to climate change may promote the persistence of invasive species and facilitate new invasions due to potentially higher tolerance to environmental stress in successful invaders. Amphibians demonstrate high levels of plasticity in life history characteristics, particularly those species which inhabit both ephemeral and permanent water bodies. We tested the influence of two projected effects of climate change (increased temperature and reduced hydroperiod) on Pacific chorus frog (Pseudacris regilla) tadpoles alone and in combination with the presence of tadpoles of a wide-spread invasive amphibian, the American bullfrog (Lithobates catesbeianus). Specifically, we explored the effects of projected climate change and invasion on survival, growth, mass at stage 42, and development rate of Pacific chorus frogs. Direct and indirect interactions between the invasive tadpole and the native tadpole were controlled via a cage treatment and were included to account for differences in presence of the bullfrog compared to competition for food resources and other direct effects. Overall, bullfrogs had larger negative effects on Pacific chorus frogs than climate conditions. Under future climate conditions, Pacific chorus frogs developed faster and emerged heavier. Pacific chorus frog tadpoles developing in the presence of American bullfrogs, regardless of cage treatment, emerged lighter. When future climate conditions and presence of invasive American bullfrog tadpoles were combined, tadpoles grew less. However, no interaction was detected between climate conditions and bullfrog presence for mass, suggesting that tadpoles allocated energy towards mass rather than length under the combined stress treatment. The maintenance of overall body condition (smaller but heavier metamorphs) when future climate conditions overlap with bullfrog presence suggests that Pacific chorus frogs may be partially compensating for the negative effects of bullfrogs via increased allocation of energy towards mass. Strong plasticity, as demonstrated by Pacific chorus frog larvae in our study, may allow species to match the demands of new environments, including under future climate change.

Population Variability of Almond-Leaved Willow (Salix triandra L.) Based on the Leaf Morphometry: Isolation by Distance and Environment Explain Phenotypic Diversity

Almond-leaved willow (Salix triandra L., Salicaceae) is a dioecious shrub, rarely a small tree that grows under various environmental conditions. We examined the population structure of 12 populations of almond-leaved willow using nine leaf morphological traits and specific leaf area. Populations were selected from a range of habitats, from continental to the sub-Mediterranean zone, to examine the influence of environmental conditions (climate and altitude) and geographic distance on leaf variability. Significant differences were confirmed among all populations for all traits, with significant correlations between geographic location of populations and morphological traits, and between environmental conditions and morphological traits. Large-leaved populations were found in continental and sub-Mediterranean climates, while small-leaved populations were found in higher elevations and smaller karstic rivers. In addition, populations from floodplains showed greater variability than populations from the karstic habitats, indicating a positive influence of lowland habitats and possible underlying differences in gene pool size. In conclusion, we found that environmental conditions and geographical distances in addition to genetic drift, are the main influences on the variability in almond-leaved willow, with the species showing a high level of plasticity and adaptation to local environmental conditions.

Root and Rhizosphere Processes under Drought: Digging Deeper to Enhance Ecosystem Resilience

Root and Rhizosphere Processes under Drought: Digging Deeper to Enhance Ecosystem Resilience

Into the wild-a field study on the evolutionary and ecological importance of thermal plasticity in ectotherms across temperate and tropical regions.

Understanding how environmental factors affect the thermal tolerance of species is crucial for predicting the impact of thermal stress on species abundance and distribution. To date, species' responses to thermal stress are typically assessed on laboratory-reared individuals and using coarse, low-resolution, climate data that may not reflect microhabitat dynamics at a relevant scale. Here, we examine the daily temporal variation in heat tolerance in a range of species in their natural environments across temperate and tropical Australia. Individuals were collected in their habitats throughout the day and tested for heat tolerance immediately thereafter, while local microclimates were recorded at the collection sites. We found high levels of plasticity in heat tolerance across all the tested species. Both short- and long-term variability of temperature and humidity affected plastic adjustments of heat tolerance within and across days, but with species differences. Our results reveal that plastic changes in heat tolerance occur rapidly at a daily scale and that environmental factors on a relatively short timescale are important drivers of the observed variation in thermal tolerance. Ignoring such fine-scale physiological processes in distribution models might obscure conclusions about species' range shifts with global climate change. This article is part of the theme issue 'Species' ranges in the face of changing environments (part 1)'.

Giant room temperature compression and bending in ferroelectric oxide pillars

Plastic deformation in ceramic materials is normally only observed in nanometre-sized samples. However, we have observed high levels of plasticity (>50% plastic strain) and excellent elasticity (6% elastic strain) in perovskite oxide Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3, under compression along <100>pc pillars up to 2.1 μm in diameter. The extent of this deformation is much higher than has previously been reported for ceramic materials, and the sample size at which plasticity is observed is almost an order of magnitude larger. Bending tests also revealed over 8% flexural strain. Plastic deformation occurred by slip along {110} <1bar{1}0 > . Calculations indicate that the resulting strain gradients will give rise to giant flexoelectric polarization. First principles models predict that a high concentration of oxygen vacancies weaken the covalent/ionic bonds, giving rise to the unexpected plasticity. Mechanical testing on oxygen vacancies-rich Mn-doped Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 confirmed this prediction. These findings will facilitate the design of plastic ceramic materials and the development of flexoelectric-based nano-electromechanical systems.

Fatigue crack growth in Ti-6Al-4V specimens produced by Laser Powder Bed Fusion and submitted to Hot Isostatic Pressing

The fatigue crack growth (FCGR) behaviour of titanium alloy Ti-6Al-4V submitted to Hot Isostatic Pressing through CT specimens manufactured by Laser Powder Bed Fusion (LPBF) is analysed. Both the crack growth under constant amplitude loading and the transient crack growth behaviour after the application of overloads or underloads were studied. The effect of the mean stress and the transient delay behaviour were studied using the crack closure parameter. The HIP treatment showed an increment in the FCGR strength increasing the fatigue threshold, the critical stress intensity factor and the FCGR resistance. Crack closure induced by plasticity for the stress ratio R = 0 was observed and for R = 0.4 no crack closure was detected. The applied overloads caused a FCGR retardation due to the increase of crack closure effect induced by plasticity resulting from the overloads while for underloads application no change in the FCGR behaviour and crack closure levels was observed. The overloads applied with 100% intensity for R = 0.4 achieved a high level of plasticity in the crack tip leading to higher crack retardation and superior transient period due to a higher zone affected by the overloads.

Сезонний ритм розвитку рослин актинідії (Actinidia arguta) в умовах Північного Степу Причорномор’я

The relevance of research on actinidia plants, which is a non-traditional uncommon fruit crop for Ukraine, is highlighted. In the conditions of introduction of the northern steppe of the Black Sea coast as a result of experimental researches dates of passing of phenological phases of two forms - female and male French selection are established. Female plants begin flowering 7 days earlier than males and bloom three days longer, regardless of the type of maturity. It was found that the biological maturity of actinidia fruits begins in the second decade of September (early - in the first), their full maturity was recorded in the late second to early third decade of September. The duration of the vegetation period of plants of different varieties and forms in the 2020 season was 229-236 days, in 2021 221-232 days, which indicates a direct dependence of plant growth and development on weather conditions. In terms of varieties, plants of medium type of development formed a yield higher than the early by 4464 g on average for two years of research. Assessment of resistance to pests and diseases in the 2020-2021 seasons showed that these objects are absent on actinidia plants, which is probably due to their absence in the new environment. The decrease in air temperature to -2… -5 oC at night in 2020 led to the freezing of young shoots and flower buds in plants of both forms. As a result, the fruit harvest was much lower than next year - 2021. For the successful cultivation of actinidia in the conditions studied, developed agronomic recommendations for the prevention of damage by low temperatures. The conclusion is made about carrying out selection works on creation of new grades of this culture, with a high level of plasticity and resistance to frosts during the growing season.

Adaptive variability of basil cultivars (Ocimum basilicum L.)

Purpose of the research was to estimate the state of varietal resources and adaptive-and-productive potential of basil plants. Methods. Field, laboratory, statistical and calculation-analytical. The field work included marking out of the experimental plot and field work. The laboratory method was used to analyze plants, assess the quality of the crop, and study physical, chemical and microbiological properties of the soil. Statistical and analytical calculation methods were used to calculate the results. Results. The varieties of ‘Temnyi Opal’, ‘MFI-2’, ‘Siaivo’ and ‘Badioryi’ where the regression coefficient was in the range of 0.57–0.78 can be included to the group of highly plastic varieties by the “commodity yield” feature according to the results of research. The highest rate of breeding value by the “plant weight” trait was observed in the variety of ‘Temnyi Opal’, Sc = 347.22. The group of highly plastic varieties on the basis of “plant weight” trait included the varieties ‘Mister Barns’, ‘MFI-2’, ‘Rutan’, ‘Siaivo’ and ‘Badioryi’, where the regression coefficient was in the range of 0.91–0.99. The varieties ‘Temnyi Opal’, ‘Yerevanskyi’, ‘Ametyst’ and ‘Lymonnyi Aromat’ were classified as intensive. The regression coefficient of these varieties was in the range of 1.03–1.16. The analysis of the combination of high productivity, quantitative characteristics of the crop structure with the level of ecological plasticity and stability indicates different ways of these indicators formation in separate varieties. It was revealed that a high level of plasticity and yield stability did not guarantee a similar result on some quantitative features of its structure. Conclusions. The degree of adaptability of basil varieties can also be assessed by the value of the parameters of features variation. The obtained results will allow more objectively assessing the adaptive-and-productive potential of varieties and qualitatively selecting initial forms for further breeding for adaptability.

Living in a Fluctuating Environment Increases Tolerance to Marine Heatwaves in the Free-Living Coralline Alga Phymatolithon lusitanicum

Recently, increased attention is being paid to the importance of environmental history in species’ responses to climate-change related stressors, as more variable and heterogeneous environments are expected to select for higher levels of plasticity in species tolerance traits, compared to stable conditions. For example, organisms inhabiting environments with highly fluctuating thermal regimes might be less susceptible to the increasing frequency and intensity of marine heatwaves (MHWs). In this study, we assessed the metabolic and calcification responses of the rhodolith-bed forming Phymatolithon lusitanicum, from a coastal region that is strongly influenced by frequent changes between upwelling and downwelling conditions, to a simulated MHW scenario, with and without prior exposure to a moderate thermal stress. This allowed determining not only the influence of the species’ long-term thermal history on its resilience against MHWs, but also the rhodoliths capacity for short-term thermal stress memory and its importance during posterior MHW-exposure. Our findings indicate that the rhodoliths experienced negative impacts on daily net primary production (DNP) and calcification (DNC) during the MHW. The effect on the former was only temporary at the beginning of the MHW, while DNC was highly impacted, but exhibited a quick recovery after the event, suggesting a high resilience of the species. Furthermore, prior exposure to a moderate temperature increase, such as those occurring frequently in the natural habitat of the species, mitigated the effects of a subsequent MHW on DNP, while promoting a faster recovery of DNC after the event. Thus, our findings (1) support the hypothesis that benthic organisms living in nearshore habitats may benefit from the natural short-term temperature fluctuations in these environments with an increased resistance to MHW impacts and (2) provide first-time evidence for thermally induced stress memory in coralline algae.