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Low temperature studies with winter-dormant buds are severely limited by the lack of a rapid,non-destructive assay for their viability. Investigations involving the winter harvest of ecodormant buds of woody subjects, including cryopreservation, are restricted if viability cannot be assessed until dormancy is broken. If post-treatment grafting indicates low survival of the harvested population then further collection and study has to be delayed until the next winter season. This study trials the use of a portable gas exchange system able to discriminate between live and dead buds rapidly, with the assay confirmed as non-destructive by subsequent micropropagation. Active respiration was recorded for 85% of a winter-dormant Malus domestica buds population that showed 91% viability when grafted (n = 45). Lethally stressed material gave no false positive results. When micropropagated after respiratory measurement, a population viability of 76% was recorded. There was a significant, positive correlation between respiration and fresh weight for buds of mass >10 mg, from a population with a mean fresh weight of 17 mg.

Interrogative proteome analyses are used to identify and quantify the expression of proteins involved in heat tolerance and to identify associated physiological processes in heat-stressed plants. The objectives of the study were to identify and quantify the expression of proteins involved in heat tolerance and to identify associated physiological processes in chickpea (Cicer arietinum L.) heat-tolerant (Acc#7) and sensitive genotype (Acc#8) from a field study. Proteomic and gene ontological analyses showed an upregulation in proteins related to protein synthesis, intracellular traffic, defence and transport in the heat-tolerant genotype compared to the susceptible one at the warmer site. Results from KEGG analyses indicate the involvement of probable sucrose-phosphate synthase (EC 2.4.1.14) and sucrose-phosphate phosphatase (EC 3.1.3.24) proteins, that were upregulated in the heat-tolerant genotype at the warmer site, in the starch and sucrose pathway. The presence of these differentially regulated proteins including HSP70, ribulose bisphosphate carboxylase/oxygenase activase, plastocyanin and protoporphyrinogen oxidase suggests their potential role in heat tolerance, at flowering growth stage, in field-grown chickpea. This observation supports unaltered physiological and biochemical performance of the heat-tolerant genotypes (Acc#7) relative to the susceptible genotype (Acc#8) in related studies (Makonya et al. 2019). Characterisation of the candidate proteins identified in the current study as well as their specific roles in the tolerance to heat stress in chickpea are integral to further crop improvement initiatives.

The effects of individual climatic factors on crops are well documented, whereas the interaction of such factors in combination has received less attention. The frequency of salinity and waterlogging stress is increasing with climate change, accompanied by elevated CO2 concentration (e[CO2]). This study explored how these three variables interacted and affected two tomato genotypes. Cultivated and wild tomato (Solanum lycopersicum and Solanum pimpinellifolium) were grown at ambient [CO2] and e[CO2], and subjected to salinity, waterlogging, and combined stress. Leaf photosynthesis, chlorophyll fluorescence, quenching analysis, pigment, and plant growth were analyzed. The response of tomatoes depended on both genotype and stress type. In cultivated tomato, photosynthesis was inhibited by salinity and combined stress, whereas in wild tomato, both salinity and waterlogging stress, alone and in combination, decreased photosynthesis. e[CO2] increased photosynthesis and biomass of cultivated tomato under salinity and combined stress compared with ambient [CO2]. Differences between tomato genotypes in response to individual and combined stress were observed in key photosynthetic and growth parameters. Hierarchical clustering and principal component analysis revealed genetic variations of tomatoes responding to the three climatic factors. Understanding the interacting effects of salinity and waterlogging with e[CO2] in tomato will facilitate improvement of crop resilience to climate change.

Computational estimation, typically construed as an approximate mental calculation of an arithmetical problem, is an important skill in everyday life and a wide range of professional contexts. Despite its importance, textbooks and curricula address it inadequately, with the consequence that many teachers are uncertain as to why and how they should teach it. In this paper, we present a narrative literature review that brings together the extensive research of the cognitive psychologists and the limited research of the mathematics educators to clarify the nature of computational estimation and its development. Focused initially on the strategies used in computational estimation before turning to children’s and adults’ computational estimation competence, the review shows that computational estimation, which develops over time, draws on a wide range of strategies reciprocally dependent on a secure understanding of numbers and arithmetic. It shows that the poor estimation competence of children and adults’ is susceptible to interventions, particularly with respect to addressing a common misconception that the purpose of computational estimation is the mental calculation of exact solutions.

Abiotic stress due to climate change with continuous rise of atmospheric CO2 concentration is predicted to cause severe changes to crop productivity. Thus, research into wheat cultivars, capable of maintaining yield under limiting conditions is necessary. The aim of this study was to investigate the physiological responses of spring wheat to individual and combined drought- and heat events and their interaction with CO2 concentration. Two heat sensitive (LM19, KU10) and two heat tolerant (LM62, GN5) genotypes were selected and grown under ambient (400 ppm, aCO2) and elevated (800 ppm, eCO2) CO2 concentrations. At the tillering stage, the wheat plants were subjected to different treatments: control, progressive drought, heat and combined drought and heat stress. Our results showed that eCO2 mitigated the negative impact of the moderate stress in all genotypes. However, no distinctive responses were observed in some of the measured parameters between heat sensitive and tolerant genotypes. All genotypes grown at eCO2 had significantly higher net photosynthetic rates and maintained maximum quantum efficiency of PSII photochemistry under heat and combined stress compared to aCO2. Under heat and combined stress, the chlorophyll a:b ratios decreased only in heat tolerant genotypes at eCO2 compared to the control. Furthermore, the heat tolerant genotypes grown at eCO2 showed an increased glucose and fructose contents and a decreased sucrose content under combined stress compared to aCO2. These findings provide new insights into the underlying mechanisms of different genotypic responses to combined abiotic stresses at eCO2 that differ from the response to individual stresses.

Deep-rooted crops, such as rapeseed have access to deep stored soil moisture unavailable to more shallow-rooted crops. However, it appears that the presence of deep roots in moist soil does not necessarily ensure full water supply and prevent drought stress during progressive soil drying. Thus, there is a need to quantify the contribution of deep roots to water uptake and investigate the role of deep roots in delaying drought stress.In large parts of Europe, climate change will lead to lower precipitation in the growing season and higher outside the growing season. This imbalance can be levelled out by growing summer crops on winter precipitation. However, it requires crops that a capable of utilizing previous surplus precipitation stored deep in the soil profile.We grew rapeseed in a large-scale semi-field setup, allowing root growth down to 4 meters depth. We monitored the development in root growth, water uptake, stomatal conductance, leaf ABA, photosynthesis, and soil water content during progressive soil drying. This allowed us to investigate the ability of rapeseed to compensate for a lack of water in the upper root zone with water uptake in the deeper root zone and to identify the onset of stress responses.

Our aim was to understand how moderately increased light intensities influenced the response of chickpea to high temperature. Three chickpea genotypes (Acc#3, Acc#7 and Acc#8) were treated at control (26 °C and 300 μmol m −2 s −1 photosynthetic photon flux density/PPFD), high temperature (38 °C and 300 μmol m −2 s −1 PPFD), increased light intensity (26 °C and 600 μmol m −2 s −1 PPFD) and combination of increased light and temperature (38 °C and 600 μmol m −2 s −1 PPFD). The net photosynthetic rate (P N) of Acc#3 and Acc#8 significantly decreased at high temperature regardless of light intensity. The P N of all three genotypes at increased light intensity was significantly higher than that at high temperature. The intracellular CO 2 concentration (C i), stomatal conductance (g s) and transpiration rate (E) of Acc#3 and Acc#8 at increased light intensity with or without high temperature significantly decreased in comparison with control and individually high temperature treatment. The relative water content of Acc#3 at high temperature and the combination treatment decreased as compared with control. The relative water content of Acc#7 at control was higher than the other three treatments. The F v/F m (Maximum quantum efficiency of photosystem II) of leaves from the three genotypes at 38 °C were lower than at 26 °C regardless of light intensity. The high temperature decreased chlorophyll content in the lower bottom leaf of Acc#7 and Acc#8 than control. In conclusion, chickpeas showed a higher net photosynthetic rate at increased light intensity to withstand heat stress, which was genotype-dependent. Physiological responses of different chickpea genotypes to increased temperature and light intensity indicated that distinct responsive mechanism of photosynthesis. This study provides information on how chickpea respond to high temperature and increased light intensity, which will help us to improve chickpea to deal with future climate changes.

In recent decades climate change has impacted ecosystems negatively globally with Mediterranean systems being particularly vulnerable. Changes in rainfall pattern and amounts have led to increases in flooding and droughts in certain areas of the world. Many important agricultural crops such as Aspalathus linearis (Burm.f.) R. Dahlgren, rooibos tea, rely on the Mediterranean-type seasonality in the Western Cape, South Africa. Aspalathus linearis plants, which occur naturally in the Cedarberg, grow in hot and dry summer conditions and have a root that penetrates the soil down to 2 m, yet no work has looked at the root response to drought under low rainfall environments. The objective of this study was to determine the physiological and morphological response of A. linearis plants grown at two different water regimes to drought. A potted glasshouse experiment was carried out where drought stress (withdrawing watering) was imposed on well-watered and low moisture supplied plants. The low moisture droughted plants exhibited drought tolerant mechanisms which included higher root/shoot ratios as well as thinner roots, both of which are effective for water and nutrient uptake. Overall, plants in the 30% FC treatment recorded lower Pmax, gs and E after three days in the drought conditions while 70% FC plants were only affected after five days. Furthermore, plants grown under low moisture conditions produced 50% lower biomass compared to plants grown under adequate moisture conditions. This implies that low rainfall and the occurrences of dry spells and drought, associated with climate change are likely to reduce the production of A. linearis in the Cederberg area.

The analysis of the content of school textbooks, particularly in a time of cross-cultural borrowing, is a growing field restricted by the tools currently available. In this paper, drawing on the analyses of three English year-one mathematics textbooks, we show how two approaches to the analysis of sequential data not only supplement conventional frequency analyses but highlight trends in the content of such textbooks hidden from frequency analyses alone. The first, moving averages, is conventionally used in science to eliminate noise and demonstrate trends in data. The second, Lorenz curves, is typically found in the social sciences to compare different forms of social phenomena. Both, as we show, extend the range of questions that can be meaningfully asked of textbooks. Finally, we speculate as to how both approaches can be used with other forms of ordered classroom data. FoNS

Ultraviolet radiation (UV, 280-400 nm) as an environmental signal triggers metabolic acclimatory responses. However, how different light qualities affect UV acclimation during growth is poorly understood. Here, cucumber plants (Cucumis sativus) were grown under blue, green, red, or white light in combination with UV. Their effects on leaf metabolites were determined using untargeted metabolomics. Blue and white growth light triggered the accumulation of compounds related to primary and secondary metabolism, including amino acids, phenolics, hormones, and compounds related to sugar metabolism and the TCA cycle. In contrast, supplementary UV in a blue or white light background decreased leaf content of amino acids, phenolics, sugars, and TCA-related compounds, without affecting abscisic acid, auxin, zeatin, or jasmonic acid levels. However, in plants grown under green light, UV-induced accumulation of phenolics, hormones (auxin, zeatin, dihydrozeatin-7-N-dihydrozeatin, jasmonic acid), amino acids, sugars, and TCA cycle-related compounds. Plants grown under red light with UV mainly showed decreased sugar content. These findings highlight the importance of the blue light component for metabolite accumulation. Also, data on interactions of UV with green light on the one hand, and blue or white light on the other, further contributes to our understanding of light quality regulation of plant metabolism., Funding agency:GUDP (Danish Ministry of Food, Agriculture and Fisheries), Denmark

In this paper, motivated in part by evidence that Swedish teachers are sceptical of parents’ abilities to offer appropriate support, we present an exploratory investigation of the activities Swedish parents initiate to facilitate their year-one (first grade) children’s learning of mathematics. Data, derived from 25 semi-structured interviews conducted with parents from three demographically different schools, were subjected to constant comparison analyses and yielded three broad categories of activity. These concerned the use of games in the learning of mathematics, contextualised mathematics activities like cooking and shopping, and decontextualised mathematics activities like systematic counting. Collectively, the results indicate that while parents of year-one children are confident supporting their children’s learning of mathematics, they are also conscious of the need to avoid both undermining schools’ efforts and exacerbating educational inequity. With few exceptions, the activities parents described were age-appropriate and more likely to complement teachers’ actions than not. FoNS

In this paper we present analyses of three textbooks currently used in the teaching of mathematics to year-one children in England. One is an established English-authored textbook, while the others are Singaporean-authored imports promoted by government as solutions to perceptions of systemic failure. Every task in each textbook was coded against a set of eight number-related competences known to support children’s learning in both short and long terms. Such a framework, which is literature-derived and curriculum-independent, enables meaningful comparison of materials deriving from different cultural contexts. Analyses of the proportions of all tasks coded for the different competences showed that none of the three books adequately addresses all eight competences, although the English-authored comes closest. Moving averages, undertaken to show the temporal location of the opportunities presented for children to acquire the eight competences, showed them distributed throughout the school year in the English-authored textbook but only during the first half of the school year in the two Singaporean-authored textbooks. Some implications for the importation of such materials are discussed. FoNS

Heat and drought events often occur concurrently as a consequence of climate change and have a severe impact on crop growth and yield. Besides, the accumulative increase in the atmospheric CO

We hypothesized that elevated [CO

Motivated by earlier research highlighting Swedish teachers’ beliefs that the setting of homework compromises deep-seated principles of educational equity, this paper presents an exploratory study of Swedish parents’ perspectives on homework in their year-one children’s learning. Twenty-five parents, drawn from three demographically different schools in the Stockholm region, participated in semi-structured interviews. The interviews, broadly focused on how parents support their children’s learning and including questions about homework in general and mathematics homework in particular, were transcribed and data subjected to a constant comparison analytical process. This yielded four broad themes, highlighting considerable variation in how parents perceive the relationship between homework and educational equity. First, all parents spoke appreciatively of their children receiving reading homework and, in so doing, indicated a collective construal that reading homework is neither homework nor a threat to equity. Second, four parents, despite their enthusiasm for reading homework, opposed the setting of any homework due to its potential compromise of family life. Third, seven parents indicated that they would appreciate mathematics homework where it were not a threat to equity. Finally, fourteen parents, despite acknowledging homework’s potential compromise to equity, were unequivocally in favour of mathematics homework being set to their children. FoNS

Expression of cucumber (Cucumis sativus) genes encoding the phenylpropanoid and flavonoid biosynthetic enzymes phenylalanine ammonia lyase (PAL), cinnamic acid 4-hydroxylase (C4H), and chalcone synthase (CHS), was studied under control light conditions (photosynthetically active radiation, PAR) in root, stem, and leaf. Furthermore, the expression was quantified in leaves illuminated with PAR and supplemental ultraviolet-A (315–400 nm) or ultraviolet-B (280–315 nm) radiation. The expression patterns of all twelve CsPAL, three CsC4H, and three CsCHS genes were established. Among the genes regulated by UV two general expression patterns emerge. One pattern applies to genes primarily regulated by enriched UV-A illumination (pattern 1). Another pattern (pattern 2) was found for the genes regulated by enriched UV-B. Three of the pattern 2 genes (CsPAL4, CsPAL10, and CsCHS2) displayed a particular sub-pattern (pattern 2b) with transcription enriched by at least 30-fold. In contrast to the other genes studied, the promoters of the genes regulated according to pattern 2b contained a combination of a number of cis-acting regulatory elements (MREs, ACEs, and G-boxes) that may be of importance for the particularly high enhancement of expression under UV-B-containing light. The regulation of phenylpropanoid and flavonoid biosynthesis genes in cucumber resembles that of a number of other plants. However, cucumber, due to its greater size, is an attractive species for combining more detailed studies of the morphology, physiological parameters and fine regulation of spatial and temporal expression of key genes. This, in turn, can facilitate the quantitative investigation of the relationships among different promoter motifs, the expression levels of each of these three genes, and metabolite accumulation profiles.

Ultraviolet (UV)-A- or UV-B-enrichment of growth light resulted in a stocky cucumber (Cucumis sativus L.) phenotype exhibiting decreased stem and petiole lengths and leaf area. Effects were larger in plants grown in UV-B- than in UV-A-enriched light. In plants grown in UV-A-enriched light, decreases in stem and petiole lengths were similar independently of tissue age. In the presence of UV-B radiation, stems and petioles were progressively shorter the younger the tissue. Also, plants grown under UV-A-enriched light significantly reallocated photosynthate from shoot to root and also had thicker leaves with decreased specific leaf area. Our data therefore imply different morphological plant regulatory mechanisms under UV-A and UV-B radiation. There was no evidence of stress in the UV-exposed plants, neither in photosynthetic parameters, total chlorophyll content, nor in accumulation of damaged DNA (cyclobutane pyrimidine dimers). The ABA content of the plants also was consistent with non-stress conditions. Parameters such as total leaf antioxidant activity, leaf adaxial epidermal flavonol content and foliar total UV-absorbing pigment levels revealed successful UV acclimation of the plants. Thus, the stocky UV-phenotype was displayed by healthy cucumber plants, implying a strong morphological response and regulatory adjustment as part of UV acclimation processes involving UV-A and/or UV-B photoreceptors.

As drought and heat stress are major challenges for crop productivity under future climate changes, tolerant cultivars are highly in demand. This study investigated the potential of existing Nordic wheat genotypes to resist unfavorable conditions. Four genotypes were selected based on their heat sensitivity (heat-sensitive: LM19, SF1, heat-tolerant: LM62, NS3). At the tillering stage, the plants were subjected to four treatments under controlled conditions: control, drought, heat and combined drought and heat stress. The morpho-physiological performance was quantified during the early and late phase of stress, as well as the recovery phase. We applied an integrative image-based phenotyping approach monitoring plant growth dynamics by structural Red Green Blue (RGB) imaging, photosynthetic performance by chlorophyll fluorescence imaging and transpiration efficiency by thermal infrared imaging. The results demonstrated that the selected genotypes were moderately affected in their photosynthetic efficiency and growth under drought stress, whereas heat and combined stress caused rapid reductions in photosynthesis and growth. Furthermore, drought stress had a major impact on canopy temperature. The NS3 genotype was the most robust genotype, as indicated by its improved response under all stress treatments due to its relatively small biomass. However, the genotypes showed different tolerance to individual and combined stress.

Ultraviolet B (UV-B, 280 – 315 nm) and ultraviolet A (UV-A, 315-400 nm) radiation comprise small portions of the solar radiation but regulate many aspects of plant development, physiology and metabolism. Until now, how plants respond to UV-B in the presence of different light qualities is poorly understood. This study aimed to assess the effects of a low UV-B dose (0.912± 0.074 kJ m-2 day-1, at a 6 h daily UV exposure) in combination with four light treatments (blue, green, red and broadband white at 210 μmol m-2 s-1 Photosynthetic active radiation [PAR]) on morphological and physiological responses of cucumber (Cucumis sativus cv. ‘Lausanna RZ F1’). We explored the effects of light quality backgrounds on plant morphology, leaf gas exchange, chlorophyll fluorescence, epidermal pigment accumulation, and on acclimation ability to saturating light intensity. Our results showed that supplementary UV-B significantly decreased biomass accumulation in the presence of broad band white, blue and green light, but not under red light. UV‐B also reduced the photosynthetic efficiency of CO2 fixation (α) when combined with blue light. These plants, despite showing high accumulation of anthocyanins, were unable to cope with saturating light conditions. No significant effects of UV-B in combination with green light were observed for gas exchange and chlorophyll fluorescence parameters, but supplementary UV-B significantly increased chlorophyll and flavonol contents in the leaf epidermis. Plants grown under red light and UV-B significantly increased maximum photosynthetic rate and dark respiration compared to pure red light. Additionally, red and UV-B treated plants during with saturating light intensity showed an higher quantum yield of photosystem II (PSII), fraction of open PSII centres and electron transport rate and showed no effect on the apparent maximum quantum efficiency of PSII photochemistry (Fv/Fm) or non-photochemical quenching in contrast to solely red-light conditions. These findings provide new insights into how plants respond to UV-B radiation in the presence of different light spectra., Funding Agencies:GUDP (Danish Ministry of Food, Agriculture and Fisheries) Research center iFood Faculty for Business, Science and Technology at Örebro University Örebro University Vice Chancellor's strategic research programme on 'Food and Health'

We hypothesized that elevated [CO2] only increases sorghum photosynthesis under low nitrogen availability and evaluated whether cultivars BRS373 (grain), BRS511 (saccharine) and BRS655 (forage) differ in their sensitivity to nitrogen and [CO2]. Plants were grown in growth chambers where air [CO2] was 400 (a[CO2]) or 800 (e[CO2]) μmol CO2 mol−1 and supplied with nutrient solution containing 211 (HN) or 48 (LN) ppm N for 45 days. Photosynthetic traits were measured in fully expanded leaves as well as leaf nitrogen and biomass accumulation. e[CO2] increased the sensitivity of photosynthesis to LN, with all sorghum cultivars having lower maximum Rubisco carboxylation rate, effective quantum efficiency of PSII and stomatal conductance at LN than at HN. As compared to HN, LN caused lower photosynthesis of BRS373 at a[CO2] and lower maximum PEPC carboxylation rate at e[CO2]. Actually, the metabolic limitation of photosynthesis by LN (Lm) was high in BRS373 at a[CO2] and slightly reduced at e[CO2]. On the other hand, Lm was increased in BRS511 and BRS655 at e[CO2]. Based on photosynthesis, the grain cultivar BRS373 was the most sensitive to LN. Although the number of leaves and of tillers and the leaf area were lower at LN than at HN for BRS373 and BRS655 after 45 days of growth, shoot biomass was not significantly affected. We found significant variation in photosynthetic responses to LN and e[CO2] among sorghum cultivars, likely associated with different patterns of nitrogen and carbon partitioning. Such findings must be considered when predicting crop performance in a changing environment.

The effect of considering cultivar differences in stomatal conductance (gs) on relative air humidity (RH)-related energy demand was addressed. We conducted six experiments in order to study the variation in evapotranspiration (ETc) of six pot rose cultivars, investigate the underlying processes and parameterise a gs-based ETc model. Several levels of crop ETc were realised by adjusting the growth environment. The commonly applied Ball–Woodrow–Berry gs-sub-model (BWB-model) in ETc models was validated under greenhouse conditions, and showed a close agreement between simulated and measured ETc. The validated model was incorporated into a greenhouse simulator. A scenario simulation study showed that selecting low-gs cultivars reduces energy demand (≤5.75%), depending on the RH set point. However, the BWB-model showed poor prediction quality at RH lower than 60% and a good fit at higher RH. Therefore, an attempt was made to improve model prediction: the in situ-obtained data were employed to adapt and extend either the BWB-model, or the Liu-extension with substrate water potential (Ψ; BWB-Liu-model). Both models were extended with stomatal density (Ds) or pore area. Although the modified BWB-Liu-model (considering Ds) allowed higher accuracy (R2 = 0.59), as compared to the basic version (R2 = 0.31), the typical lack of Ψ prediction in greenhouse models may be problematic for implementation into real-time climate control. The current study lays the basis for the development of cultivar specific cultivation strategies as well as improving the gs sub-model for dynamic climate conditions under low RH using model-based control systems.

Using dill (Anethum graveolens L.) as a model herb, we revealnovel associations between metabolite profile and sensory quality, by integrating non-target metabolomics with sensory data. Low night temperatures and exposure to UV-enriched light was used to modulate plant metabolism, thereby improving sensory quality. Plant age is a crucial factor associated with accumulation of dill ether and α-phellandrene, volatile compounds associated with dill flavour. However, sensory analysis showed that neither of these compounds has any strong association with dill taste. Rather, amino acids alanine, phenylalanine, glutamic acid, valine, and leucine increased in samples exposed to eustress and were positively associated with dill and sour taste. Increases in amino acids and organic acids changed the taste from lemon/grass to a more bitter/pungent dill-related taste. Our approach reveals a novel approach to establish links between effects of eustressors on sensory quality, and may be applicable to a broad range of crops., Funding Agencies:Faculty for Business, Science and Technology at Örebro University Örebro University Vice Chancellor's strategic research programme on 'Food and Health' Science Foundation Ireland S16/IA/4418

In this paper we present statistical analyses of three textbooks used by Swedish teachers to support year one children’s learning of mathematics. One, Eldorado, is authored by Swedish teachers, another, Favorit, is a Swedish adaptation of a popular Finnish series and the third, Singma, is a Swedish adaptation of a Singapore series. Data were coded against the eight categories of foundational number sense, which are the number-related competences literature has shown to be essential for the later mathematical success of year one learners. Two analyses were undertaken; the first was a frequency analysis of the tasks coded for a particular category, the second was a time-series analysis highlighting the temporal location of such opportunities. The frequency analyses identified statistically significant differences with respect to children’s opportunities to acquire foundational number sense. Additionally, the time series showed substantial differences in the ways in which such tasks were located in the structure of the textbooks. Such differences, we argue, offer substantial didactical challenges to teachers trying to adapt their practices to the expectations of such imports.

Ultraviolet (UV) light induces a stocky phenotype in many plant species. In this study, we investigate this effect with regard to specific UV wavebands (UV-A or UV-B) and the cause for this dwarfing. UV-A- or UV-B-enrichment of growth light both resulted in a smaller cucumber (Cucumis sativus L.) phenotype, exhibiting decreased stem and petiole lengths and leaf area (LA). Effects were larger in plants grown in UV-B- than in UV-A-enriched light. In plants grown in UV-A-enriched light, decreases in stem and petiole lengths were similar independent of tissue age. In the presence of UV-B radiation, stems and petioles were progressively shorter the younger the tissue. Also, plants grown under UV-A-enriched light significantly reallocated photosynthates from shoot to root and also had thicker leaves with decreased specific LA. Our data therefore imply different morphological plant regulatory mechanisms under UV-A and UV-B radiation. There was no evidence of stress in the UV-exposed plants, neither in photosynthetic parameters, total chlorophyll content, or in accumulation of damaged DNA (cyclobutane pyrimidine dimers). The abscisic acid content of the plants also was consistent with non-stress conditions. Parameters such as total leaf antioxidant activity, leaf adaxial epidermal flavonol content and foliar total UV-absorbing pigment levels revealed successful UV acclimation of the plants. Thus, the UV-induced dwarfing, which displayed different phenotypes depending on UV wavelengths, occurred in healthy cucumber plants, implying a regulatory adjustment as part of the UV acclimation processes involving UV-A and/or UV-B photoreceptors., Funding agencies:Science Foundation Ireland (S16/IA/4418)Flemish Science Foundation (FWO, grant G000515N)China Scholarship Council (CSC no. 201406320076)

During recent years we have advanced our understanding of plant molecular responses to ultraviolet radiation (UV, 280-400 nm); however, how plants respond to UV radiation under different spectral light qualities is poorly understood. In this study, cucumber plants (Cucumis sativus ‘Lausanna RZ F1’) were grown under monochromatic blue, green, red and broadband white light in combination with UV radiation. The effects of light quality and UV radiation on acclimatory responses were assessed by measuring transcript accumulation of ELONGATED HYPOCOTYL 5 (HY5), CHALCONE SYNTHASE 2 (CHS2) and LIGHT HARVESTING COMPLEX II (LHCII), and the accumulation of flavonoids and hydroxycinnamic acids in the leaves. The growth light backgrounds differentially regulated gene expression and metabolite accumulation. While HY5 and CHS2 transcripts were induced by blue and white light, LHCII was induced by white and red light. Furthermore, UV radiation antagonized the effects of blue, red, green, and white light on transcript accumulation in a gene dependent manner. Plants grown under blue light with supplementary UV radiation increased phenylalanine, flavonol disaccharide I and caffeic acid contents compared to those exposed only to blue light. UV radiation also induced the accumulation of flavonol disaccharide I and II, ferulic acid hexose and coumaric acid hexose in plants grown under green light. Our findings provide further understanding of plant responses to UV radiation in combination with different light spectra and contribute to the design of light recipes for horticultural practices that aim to modify plant metabolism and ultimately improve crop quality., Funding agencies:GUDP (Danish Ministry of Food, Agriculture and Fisheries)Faculty for Business, Science and Technology at Örebro UniversityÖrebro University

Abiotic stress tolerance in plants is said to be induced by pre‐stress events (priming) during the vegetative phase. We aimed to test whether drought priming could improve the heat and drought tolerance in wheat cultivars. Two wheat cultivars “Gladius” and “Paragon” were grown in a fully controlled gravimetric platform and subjected to either no stress or two drought cycles during the tillering stage. At anthesis, both batches were either subjected to high temperature stress, drought stress or kept as control. No alleviation of grain yield reduction due to priming was observed. Higher CO2 assimilation rates were achieved due to priming under drought stress. Yield results showed that priming was not damage cumulative to wheat. Priming was responsible to alleviated biochemical photosynthetic limitations under drought stress and sustained photochemical utilization under heat stress in “Paragon.” Priming as a strategy in abiotic stress alleviation was better evidenced in the stress susceptible cultivar “Paragon” than tolerant cultivar “Gladius”; therefore, the type of response to priming appears to be cultivar dependable, and thus phenotypical variation should be expected when studying the effects of abiotic priming.

Abiotic stress due to climate change with continuous rise of atmospheric CO