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The contribution of spike photosynthesis to grain yield (GY) has been overlooked in the accurate spectral prediction of yield. Thus, it’s essential to construct and estimate a yield-related phenotypic trait considering spike photosynthesis. Based on field and spectral reflectance data from 19 wheat cultivars under two nitrogen fertilization conditions in two years, our objectives were to (i) construct a yield-related phenotypic trait (spike–leaf composite indicator, SLI) accounting for the contribution of the spike to photosynthesis, (ii) develop a novel spectral index (enhanced triangle vegetation index, ETVI3) sensitive to SLI, and (iii) establish and evaluate SLI estimation models by integrating spectral indices and machine learning algorithms. The results showed that SLI was sensitive to nitrogen fertilizer and wheat cultivar variation as well as a better predictor of yield than the leaf area index. ETVI3 maintained a strong correlation with SLI throughout the growth stage, whereas the correlations of other spectral indices with SLI were poor after spike emergence. Integrating spectral indices and machine learning algorithms improved the estimation accuracy of SLI, with the most accurate estimates of SLI showing coefficient of determination, root mean square error (RMSE), and relative RMSE values of 0.71, 0.047, and 26.93%, respectively. These results provide new insights into the role of fruiting organs for the accurate spectral prediction of GY. This high-throughput SLI estimation approach can be applied for wheat yield prediction at whole growth stages and may be assisted with agronomical practices and variety selection. [ABSTRACT FROM AUTHOR]

The need for consumption of mustard plant (Brassica juncea L.) has increased every year. One of the efforts to increase its production and quality by applications of inorganic and organic fertilizer. This study aimed to evaluate the productivity of mustard plants treated with liquid organic fertilizer, a byproduct of black soldier fly (BSF), and inorganic fertilizer (NPK). Mustard plants were grown at Karanggayam Research Station, Caturtunggal, Depok, Sleman, Yogyakarta were treated with water as a control, NPK fertilizer, DoctoRS organic fertilizer at 0.05%, organic fertilizer A, and B at 0.1, 0.15, 0.20, and 0.25%. The effects of treatments to the phenotypic and the chlorophyll of the mustards were done after 2 weeks of treatments. The results showed that there were significant different on the stem height, number of leaves, leaf width, leaf length, and wet weight. These were in line with the total chlorophyll. Liquid organic fertilizer content analysis showed that DoctoRS liquid organic fertilizer and liquid organic fertilizer A were the most in accordance with the national standards for organic fertilizers on the parameters of pH, Mg, Ca, and TPC. [ABSTRACT FROM AUTHOR]

Plant roots exhibit plasticity in their branching patterns to forage efficiently for heterogeneously distributed resources, such as soil water. The xerobranching response represses lateral root formation when roots lose contact with water. Here, we show that xerobranching is regulated by radial movement of the phloem-derived hormone abscisic acid, which disrupts intercellular communication between inner and outer cell layers through plasmodesmata. Closure of these intercellular pores disrupts the inward movement of the hormone signal auxin, blocking lateral root branching. Once root tips regain contact with moisture, the abscisic acid response rapidly attenuates. Our study reveals how roots adapt their branching pattern to heterogeneous soil water conditions by linking changes in hydraulic flux with dynamic hormone redistribution. [ABSTRACT FROM AUTHOR]

The regulation of resource allocation in biological systems observed today is the cumulative result of natural selection in ancestral and recent environments. To what extent are observed resource allocation patterns in different photosynthetic types optimally adapted to current conditions, and to what extent do they reflect ancestral environments? Here, we explore these questions for C3, C4, and C3–C4 intermediate plants of the model genus Flaveria. We developed a detailed mathematical model of carbon fixation, which accounts for various environmental parameters and for energy and nitrogen partitioning across photosynthetic components. This allows us to assess environment-dependent plant physiology and performance as a function of resource allocation patterns. Models of C4 plants optimized for conditions experienced by evolutionary ancestors perform better than models accounting for experimental growth conditions, indicating low phenotypic plasticity. Supporting this interpretation, the model predicts that C4 species need to re-allocate more nitrogen between photosynthetic components than C3 species to adapt to new environments. We thus hypothesize that observed resource distribution patterns in C4 plants still reflect optimality in ancestral environments, allowing the quantitative inference of these environments from today's plants. Our work allows us to quantify environmental effects on photosynthetic resource allocation and performance in the light of evolutionary history. [ABSTRACT FROM AUTHOR]

Floral morphology and pigmentation are both charismatic and economically relevant traits associated with cultivated sunflower (Helianthus annuus L.). Recent work has linked floral morphology and pigmentation to pollinator efficiency and seed yield. Understanding the genetic architecture of such traits is essential for crop improvement, and gives insight into the role of genetic constraints in shaping floral diversity. A diversity panel of 288 sunflower genotypes was phenotyped for a variety of morphological, phenological, and color traits in both a greenhouse and a field setting. Association mapping was performed using 5788 SNP markers using a mixed linear model approach. Several dozen markers across 10 linkage groups were significantly associated with variation in morphological and color trait variation. Substantial trait plasticity was observed between greenhouse and field phenotyping, and associations differed between environments. Color traits mapped more strongly than morphology in both settings, with markers together explaining 16% of petal carotenoid content in the greenhouse, and 17% and 24% of variation in disc anthocyanin presence in the field and greenhouse, respectively. Morphological traits like disc size mapped more strongly in the field, with markers together explaining up to 19% of disc size variation. Loci identified here through association mapping within cultivated germplasm differ from those identified through biparental crosses between modern cultivated sunflower and either its wild progenitor or domesticated landraces. Several loci lie within genomic regions involved in domestication. Differences between phenotype expression under greenhouse and field conditions highlight the importance of plasticity in determining floral morphology and pigmentation. [ABSTRACT FROM AUTHOR]

Recognition and exploitation of hybrid vigor or heterosis among individual crosses of plants and animals has a long and distinguished history. Its manifestation is influenced by a combination of genetic, epigenetic, phenotypic, and environmental factors. Although heterosis is known to be governed by both dominant and epistatic gene action, its expression is greatly influenced by nonlinear interaction among epigenetic and phenotypic (phenomic) components. The magnitude of heterosis is generally inferred post hoc by the phenotypic performance of hybrids among laboriously made individual crosses. The expression of dominance, however, is nonlinear at the cellular level and obeys the principles underlying metabolic flux. Then, is it possible to exploit these relationships to predict heterosis? Vasseur and colleagues have indeed demonstrated the feasibility of such an approach in a series of experiments taking integrated biochemical and computational approaches, as well as testing these results on large samples of model organisms. The results offer promise toward phenomic prediction of heterosis across a wide array of organisms. [ABSTRACT FROM AUTHOR]

Heterosis describes the phenotypic superiority of hybrids over their parents in traits related to agronomic performance and fitness. Understanding and predicting nonadditive inheritance such as heterosis is crucial for evolutionary biology as well as for plant and animal breeding. However, the physiological bases of heterosis remain debated. Moreover, empirical data in various species have shown that diverse genetic and molecular mechanisms are likely to explain heterosis, making it difficult to predict its emergence and amplitude from parental genotypes alone. In this study, we examined a model of physiological dominance initially proposed by Sewall Wright to explain the nonadditive inheritance of traits like metabolic fluxes at the cellular level. We evaluated Wright's model for two fitness-related traits at the whole-plant level, growth rate and fruit number, using 450 hybrids derived from crosses among natural accessions of A. thaliana. We found that allometric relationships between traits constrain phenotypic variation in a nonlinear and similar manner in hybrids and accessions. These allometric relationships behave predictably, explaining up to 75% of heterosis amplitude, while genetic distance among parents at best explains 7%. Thus, our findings are consistent with Wright's model of physiological dominance and suggest that the emergence of heterosis on plant performance is an intrinsic property of nonlinear relationships between traits. Furthermore, our study highlights the potential of a geometric approach of phenotypic relationships for predicting heterosis of major components of crop productivity and yield. [ABSTRACT FROM AUTHOR]

Background and Aims Depending on the species, water stress affects different growth and developmental processes, mainly due to changes in hydraulic properties and hormonal signalling. This study compared the impact of water stress on tree development and organ growth in three apple cultivars. Methods Trees were differentially irrigated to induce water stress or to provide well-watered conditions in their second and third years of growth. Effects of water stress were evaluated at tree scale by shoot number and proportions of the different types of shoots, and at shoot scale by metamer appearance rate, growth duration and arrest time, as well as organ size. Key Results Water stress promoted early growth cessation, prolonged summer arrests and decreased growth resumptions, thus modifying within-tree shoot demography in favour of short shoots. Growth cessations occurred in mild water stress conditions before any difference in stem water potential appeared. No major impact was observed on organ size. Consistently with tree ontogeny, the number of shoots that resumed growth after summer arrest decreased with years, but more in water-stressed than well-watered conditions. Conclusions Even though the impact of water stress differed slightly among cultivars, the reduction in neoformation and increase in summer arrest played a common role in apple tree morphological responses and led to stress avoidance by early reduction of tree leaf area. [ABSTRACT FROM AUTHOR]

Highlights • At the Lake Garda, Cistus albidus is in conditions of extreme range marginality. • Here, it shows a high adaptive potential due to genetic and ecological factors. • It has a high phenotypic plasticity and good levels of genetic variation. • Phenological response is much higher than what is known for the Mediterranean species. • Bayesian analysis does not support any genetic structuring of the population. Abstract The potential effects of climate change on the distribution of Mediterranean plants at their peripheral range make them extremely vulnerable to environmental fluctuations. The northern-most Italian population of Cistus albidus provides an outstanding case for study, as it grows at the extreme northern edge of its range and because phenological data have been available since the early XIX century. In the period 2012–2017, we analysed the population demography and spatial structure, growth and flowering phenology, and genetic variability to understand the history, current state and possible evolution of this population. Lastly, the population data were tested for association with environmental factors. The population studied consists of plants on average 10 years old, showing the highest growth rates in spring and autumn. Anthesis starts in April and ends in early June and is significantly dependent on temperature. High levels of genetic variability are present (average H e = 0.471), with heterozygote excess detected at four loci out of five. Bayesian analysis does not support any genetic structuring of the population. The aggregated pattern in the distribution of individuals and their phenological traits, together with the absence of genetic structuring, seem to suggest that this extreme geographical population is not currently endangered. [ABSTRACT FROM AUTHOR]

Understanding intraspecific variation in the vulnerability of the xylem to hydraulic failure during drought is critical in predicting the response of forest tree species to climate change. However, few studies have assessed intraspecific variation in this trait, and a likely limitation is the large number of measurements required to generate the standard 'vulnerability curve' used to assess hydraulic failure. Here we explore an alternative approach that requires fewer measurements, and assess within species variation in leaf xylem vulnerability in Eucalyptus globulus Labill., an ecologically and economically important species with known genetic variation in drought tolerance. Using this approach we demonstrate significant phenotypic differences and evidence of plasticity among two provenances with contrasting drought tolerance. Few studies assess the range in drought tolerance that exists among individuals of the same species, yet this is critical in accurately predicting the effect of climate change on plants. This may be the result of the labour intensive process of assessing drought tolerance, which typically requires multiple measurements per individual. Here we present an alternative approach for large-scale analysis that reduces the number of measurements, thereby improving efficiency and increasing our ability to assess a broader range of individuals. [ABSTRACT FROM AUTHOR]

In general, studies on plant phenotypic plasticity concentrate on plant responses to different levels of a single environmental factor. Under natural conditions, however, multiple environmental factors often vary simultaneously. I studied the consequences for lifetime fitness caused by single treatments or treatment combinations by investigating patterns of phenotypic plasticity within and between generations. The parental plants (three genotypes of the annual plant Arabidopsis thaliana) received zero, one or two stress treatments at an early life‐stage. The treatments included wounding, shading, chilling, and their pairwise combinations. In the second generation, offspring of treated plants received either the parental or no treatment. Offspring of non‐treated plants were reared under all treatment conditions. Plants responded strongly to the treatments, especially through delayed reproduction, which positively affected lifetime fitness. Notably, treatment combinations triggered stronger plastic responses on average. Because the delay in reproduction was offset by a delay in senescence, the treatments resulted in a fitness gain instead of a loss. However, under adverse environmental conditions, this delay represents a potential fitness cost, especially when the time for reproduction is limited. The treatments 'wounding' and 'shading' triggered parental effects that increased fitness only in plants that themselves received the treatment. Untreated offspring of wounded or shaded parents performed like control plants. Also, these parental effects were not accompanied by potential fitness costs, such as delayed reproduction. Chilling triggered genotype‐specific parental effects that increased or reduced fitness. Of the treatment combinations only 'wounding' and 'shading' resulted in genotype‐specific parental effects that increased or reduced fitness independently of offspring treatment. These results suggest that the response of annual plants to treatment combinations triggers predominantly within‐generation plastic responses that include potential fitness costs, which cannot be inferred from studies that manipulate environmental factors individually. Therefore, single treatment studies likely underestimate the costs of plasticity in natural environments. [ABSTRACT FROM AUTHOR]

Ecological stability and plasticity of maize hybrids in different groups of ripeness - Knezha 307, Knezha 435, Knezha 509 and Knezha M625 by the traits grain yield and length of the ear was evaluated. The ecological parameters were determined by using the method of Eberhart and Russell (1966) and of Pakudin and Lopatina (1984). In the period of study (2014-2017) the hybrids demonstrate different plasticity and stability by the examined traits. The results of the analysis of the variances demonstrate reliable differences of the hybrids and the conditions for the two traits and primarily reliable interaction genotype - environment. The variances of the regression Si2 of all hybrids for the trait grain yield reliably differ from their theoretical value which determines them as plastic, i.e. responsive to more favourable conditions of growth. According to the values of bi the hybrid Knezha 435 (bi<1) is stable by the trait grain yield, the hybrids Knezha 307 and Knezha M625 are with values of bi close to one and have relatively medium stability and Knezha 509 with bi>1 is unstable. With reliable values of Si2 for the trait length of the ear is only the hybrid Knezha M625. The ecological stability of the other hybrids was evaluated by the value of the coefficient of regression (bi). Increased stability by this trait is demonstrated by Knezha 435, followed by Knezha 509. Knezha 307 is with medium stability (bi=1.1) by the respective trait. [ABSTRACT FROM AUTHOR]

This paper demonstrates the application of aerial multispectral images in cotton plant phenotyping. Four phenotypic traits (plant height, canopy cover, vegetation index, and flower) were measured from multispectral images captured by a multispectral camera on an unmanned aerial system. Data were collected on eight different days from two fields. Ortho-mosaic and digital elevation models (DEM) were constructed from the raw images using the structure from motion (SfM) algorithm. A data processing pipeline was developed to calculate plant height using the ortho-mosaic and DEM. Six ground calibration targets (GCTs) were used to correct the error of the calculated plant height caused by the georeferencing error of the DEM. Plant heights were measured manually to validate the heights predicted from the imaging method. The error in estimation of the maximum height of each plot ranged from -40.4 to 13.5 cm among six datasets, all of which showed strong linear relationships with the manual measurement (R2 > 0.89). Plot canopy was separated from the soil based on the DEM and normalized differential vegetation index (NDVI). Canopy cover and mean canopy NDVI were calculated to show canopy growth over time and the correlation between the two indices was investigated. The spectral responses of the ground, leaves, cotton flower, and ground shade were analyzed and detection of cotton flowers was satisfactory using a support vector machine (SVM). This study demonstrated the potential of using aerial multispectral images for high throughput phenotyping of important cotton phenotypic traits in the field. [ABSTRACT FROM AUTHOR]

Summary: Heteromorphic diaspores (fruits and seeds) are an adaptive bet‐hedging strategy to cope with spatiotemporally variable environments, particularly fluctuations in favourable temperatures and unpredictable precipitation regimes in arid climates.We conducted comparative analyses of the biophysical and ecophysiological properties of the two distinct diaspores (mucilaginous seed (M+) vs indehiscent (IND) fruit) in the dimorphic annual Aethionema arabicum (Brassicaceae), linking fruit biomechanics, dispersal aerodynamics, pericarp‐imposed dormancy, diaspore abscisic acid (ABA) concentration, and phenotypic plasticity of dimorphic diaspore production to its natural habitat and climate.Two very contrasting dispersal mechanisms of the A. arabicum dimorphic diaspores were revealed. Dehiscence of large fruits leads to the release of M+ seed diaspores, which adhere to substrata via seed coat mucilage, thereby preventing dispersal (antitelechory). IND fruit diaspores (containing nonmucilaginous seeds) disperse by wind or water currents, promoting dispersal (telechory) over a longer range.The pericarp properties confer enhanced dispersal ability and degree of dormancy on the IND fruit morph to support telechory, while the M+ seed morph supports antitelechory. Combined with the phenotypic plasticity to produce more IND fruit diaspores in colder temperatures, this constitutes a bet‐hedging survival strategy to magnify the prevalence in response to selection pressures acting over hilly terrain. [ABSTRACT FROM AUTHOR]

ContentsSummary1253I.Introduction1253II.What is the rate and molecular spectrum of spontaneous epimutations?1254III.Do spontaneous epimutations have phenotypic consequences?1257IV.Conclusion and discussion1258Acknowledgements1258References1258 Summary: Heritable gains or losses of cytosine methylation can arise stochastically in plant genomes independently of DNA sequence changes. These so‐called 'spontaneous epimutations' appear to be a byproduct of imperfect DNA methylation maintenance and epigenome reinforcement events that occur in specialized cell types. There is continued interest in the plant epigenetics community in trying to understand the broader implications of these stochastic events, as some have been shown to induce heritable gene expression changes, shape patterns of methylation diversity within and among plant populations, and appear to be responsive to multi‐generational environmental stressors. In this paper we synthesized our current knowledge of the molecular basis and functional consequences of spontaneous epimutations in plants, discuss technical and conceptual challenges, and highlight emerging research directions. [ABSTRACT FROM AUTHOR]

Phenotypic plasticity is important for species responses to global change and species coexistence. Phenotypic plasticity differs among species and traits and changes across environments. Here, we investigated phenotypic plasticity of the widespread grass Arrhenatherum elatius in response to winter warming and frost stress by comparing phenotypic plasticity of 11 geographically and environmentally distinct populations of this species to phenotypic plasticity of populations of different species originating from a single environment. The variation in phenotypic plasticity was similar for populations of a single species from different locations compared to populations of functionally and taxonomically diverse species from one environment for the studied traits (leaf biomass production and root integrity after frost) across three indices of phenotypic plasticity (RDPI, PIN, slope of reaction norm). Phenotypic plasticity was not associated with neutral genetic diversity but closely linked to the climate of the populations' origin. Populations originating from warmer and more variable climates showed higher phenotypic plasticity. This indicates that phenotypic plasticity can itself be considered as a trait subject to local adaptation to climate. Finally, our data emphasize that high phenotypic plasticity is not per se positive for adaptation to climate change, as differences in stress responses are resulting in high phenotypic plasticity as expressed by common plasticity indices, which is likely to be related to increased mortality under stress in more plastic populations. Phenotypic plasticity of populations within a single species varied as much as phenotypic plasticity among functionally and taxonomically diverse species, all stemming from the same environment, indicating a high degree of selection on the studied traits across three indices of phenotypic plasticity (RDPI, PIN, slope of reaction norm). Levels of phenotypic plasticity were not associated with neutral genetic diversity but closely linked to the climate of origin of the populations with populations stemming from warmer and more variable climates showing higher phenotypic plasticity, implying local adaptation of phenotypic plasticity itself. Finally, our data emphasizes that high phenotypic plasticity is not per se positive for adaptation to climate change, as mortality increased in parallel. [ABSTRACT FROM AUTHOR]

Increasingly large presence‐only survey datasets are becoming available for use in conservation assessments. Potentially, these records could be used to determine spatial patterns of plant species rarity and endemism. We test the integration of a large South Korean species record database with Rabinowitz rarity classes. Rabinowitz proposed seven classes of species rarity using three variables: geographic range, habitat specificity, and local population size. We estimated the range size and local abundance of 2,215 plant species from species occurrence records and habitat specificity as the number of landcover types each species' records were found in. We classified each species into a rarity class or as common, compared species composition by class to national lists, and mapped the spatial pattern of species richness for each rarity class. Species were classed to narrow or wide geographic ranges using 315 km, the average from a range size index of all species (Dmax), based on maximum distance between observations. There were four classes each within the narrow and wide range groups, sorted using cutoffs of local abundance and habitat specificity. Nationally listed endangered species only appeared in the narrow‐range classes, while nationally listed endemic species appeared in almost all classes. Species richness in most rarity classes was high in northeastern South Korea especially for species with narrow ranges. Policy implications. Large presence‐only surveys may be able to estimate some classes of rarity better than others, but modification to include estimates of local abundance and habitat types, could greatly increase their utility. Application of the Rabinowitz rarity framework to such surveys can extend their utility beyond species distribution models and can identify areas that need further surveys and for conservation priority. Future studies should be aware of the subjectivity of the rarity classification and that regional scale implementations of the framework may differ. Increasingly available large species observation datasets provide opportunity for greater insights about landscape biodiversity and patterns of species rarity than simply applying species distribution models. We assess the species rarity classification and spatial results of integrating Rabinowitz (1981) species rarity classes with 2,215 plant species from a national‐scale survey. [ABSTRACT FROM AUTHOR]

Intraspecific trait variation within natural populations (i.e. intra‐population trait variation, IPTV) is the basic source for selection and can have significant ecological consequences. Higher IPTV may increase a population's niche breath and benefit interspecies competition under a resource‐limited environment, thus affecting the ability of a species to move into novel habitats. However, the reciprocal influences of variation in environmental conditions and phenotypic trait expression in spreading plant populations are not clearly defined. We propose that during invasion, IPTV and its relative change in response to key resource enrichment may increase with the resource deficit of invaded sites, and that this relationship may facilitate plant invasions into resource‐limited environments. We analyzed the invasion trend, IPTV and its response to water enrichment, and moisture variability among populations of an annual grass Brachypodium hybridum in California, United States. We incorporated a genotyping‐by‐sequencing approach, a common garden experiment that had two water level treatments, and public plant and climate databases. Our hypothesis was supported by the observation that for populations that invaded sites with higher spring moisture deficit, both their seed biomass IPTV (for the water‐enriched treatment only) and relative change of the IPTV across water treatments were larger when examined in the common garden experiment. A generally north to south spreading direction was found in these B. hybridum populations, towards a drier and warmer climate exhibiting higher moisture deficit for plant growth. Our results suggest a role for interactions between IPTV (rather than trait means) and environmental resource availability in promoting plant invasions, providing new insights into the significance of IPTV in shaping plant geographic distributions. [ABSTRACT FROM AUTHOR]

The plasticity of functional traits promotes invasiveness of a species. Biomass allocation, as one of these traits, is responsible for resource acquisition, and its plastic modifications can be of adaptive value in new environments before any genetic adaptations may occur. Our aim was to compare in situ biomass allocation in aboveground and belowground organs in an Antarctic and a Polish population of annual bluegrass (Poa annua), the only alien plant species successfully invading Antarctica. The Antarctic population was characterised by three times lower aboveground biomass, more compact plant growth habit and higher fraction of biomass allocated into belowground organs than in the Polish population. The differences between populations are probably a result of adaptation to local conditions. The modifications of the studied traits in the Antarctic population are most likely a response to extreme atmospheric and edaphic conditions and enable the species to survive and spread in this hostile environment. Our results are in accordance with the balanced growth hypothesis. At the same time, these trait values enhance species performance under Antarctic conditions making P. annua a potential threat to local plant communities under altering climate changes and growing human impact scenario. [ABSTRACT FROM AUTHOR]

Seasonal developmental plasticity, which consists of season‐dependent alternations of developmental processes, has evolved to produce optimal phenotypes depending on specific periods in a year. For example, many phenological events in plants, such as flowering, fruiting, bud blast, bud formation, and growth cessation, are often controlled seasonally. Although temperature and photoperiod are the two major seasonal cues for such responses, the importance of phase lag between annual oscillations of the two signals has been unexplored, despite its universal nature in the context of seasonal environments. In this article, the phase‐lag calendar hypothesis (New Phytologist, 210, 2016, 399), especially the one between temperature and photoperiod, is explained using meteorological data obtained from central Japan as an example. We set forth to show how, for a narrow window in time of a couple of weeks in a year, simple threshold responses to these two signals that differ in annual oscillation phases are enough to make developmental plasticity to be expressed as phenological events. The properties of the underlying mechanisms of the events in different seasons are further predicted, and the responses are compared with reported empirical examples. Because many organisms have evolved under the phase lag between photoperiod and temperature, the developmental plasticity in response to the phase lag should be evaluated for diverse organisms. Although temperature and photoperiod are the two major seasonal cues for organismal responses, the importance of phase lag between annual oscillations of the two signals has been unexplored, despite its universal nature in the context of seasonal environments. In this article, the phase‐lag calendar hypothesis, especially the one between temperature and photoperiod, is explained using meteorological data obtained from central Japan as an example. [ABSTRACT FROM AUTHOR]

Premise of the Study: Ecologists generally agree that weak interspecific competition for light contributes to high plant species diversity in ecosystems with nutrient‐poor soils. However, the role of competition for light in such ecosystems that are also maintained by fire is poorly understood. I quantified intra‐ and interspecific competition for light in a fire‐maintained nutrient‐poor pine savanna by contrasting the effects of conspecific and heterospecific neighbors of the pale pitcher plant, Sarracenia alata. Methods: Accounting for initial neighbor abundance/aboveground production and initial transplant size, I measured growth and survival of small and large pitcher plant ramets of Sarracenia alata transplanted to the vicinity of natural, undisturbed mixtures of large pitcher plants and their heterospecific neighbors in the field. I tested competition for light and nutrients by clipping conspecific neighbors and by excluding prey from unclipped neighbors of transplants. I tested interspecific competition by uprooting heterospecific neighbors. Key Results: Plant survivorship increased when conspecific neighbors were clipped and/or starved but not when heterospecific neighbors were uprooted. Small pitcher plants benefited from clipping large conspecific neighbors, suggesting that competition for light was important. Large pitcher plants benefited from excluding prey from their neighbors, with no additional benefit of clipping, suggesting that competition for prey limited their survival. Transplants produced new pitchers that were taller with narrower openings (i.e., shade avoidance) when heterospecific neighbors were left intact but not when conspecifics were unclipped. Conclusions: Results demonstrate size‐dependent intraspecific competition for light and nutrients and interspecific shade avoidance in Sarracenia alata, which could be important to understanding species coexistence in fire‐maintained nutrient‐poor ecosystems. [ABSTRACT FROM AUTHOR]

The aim of this project was to compare the phenotypic responses of global populations of Lythrum salicaria in cold/dry and hot/humid environments to determine if phenotypic plasticity varied between the native and invasive ranges, and secondarily if this variation was linked to genetic diversity. Common garden studies were conducted in Třeboň, Czech Republic, and Lafayette, Louisiana, USA (cold/dry vs. hot/humid garden, respectively), using populations from latitudinal gradients in Eurasia and North America. Lythrum salicaria seeds collected from the same maternal plants across these latitudinal gradients were germinated and grown in Třeboň and Lafayette. Tissue masses (above-, below-ground, inflorescence and total) of these individuals were assessed at the end of each growing season (2006–2008). Worldwide field measurements of L. salicaria height were made by volunteers from 2004–2016. Biomass and height data were analyzed using the General Linear Model framework and multivariate techniques. Molecular markers (amplified fragment length polymorphisms) of individuals used in the common garden study were analyzed using traditional genetic diversity metrics and Bayesian clustering algorithms in STRUCTURE. Reaction norms were developed from differences in maternal plant responses in Třeboň versus Lafayette. In the common garden studies, stem/leaf, root and total biomass generally were highest for individuals grown from seeds collected in the southern part of the range in the cold garden, particularly by the third year of the study. In contrast, inflorescence biomass in the cold garden was higher by the third year in individuals from mid-latitude populations. As measured by volunteers, plants were taller in Eurasia than in North America moving from north to south with the pattern switching southward of 40°N latitude. Genetic diversity was similar between native and non-native invasive populations regardless of geographical origin of the seed and was not significantly different in the GLM Select model (p > 0.05). Reaction norm slopes showed that Eurasia had larger values than North America for reaction norms for above-ground and total biomass. Plants from the seeds of mother plants from Turkey had wide variation in total biomass when grown in Třeboň versus Lafayette; this variation in response within certain populations may have contributed to the lack of population-level differences in plasticity. These results indicate no loss of genetic diversity for L. salicaria during its North American invasion, nor reduction in plastic tissue allocation responses to a varying environment, which may help explain some of its invasive qualities and which could be of adaptive value under changing future environments. [ABSTRACT FROM AUTHOR]

Highlights • Grain quality associated with environmental conditions between GS31 and 200 °Cd after flowering. • In stressful environments, trade-offs between yield and quality were important. • Water soluble carbohydrates were the crux of these trade-offs. • Breeding targets "specialist" phenotypes for grain and fodder but traits meeting market standards spread across types. • "Generalist" phenotypes can accommodate multiple agronomic uses but specialists are required where trade-offs are involved. Abstract The profitability of oat crops depends on quality attributes in relation to milling and hay marketing standards. The aims of this paper were to (i) quantify grain and hay quality traits in varieties and advanced grain, hay and grazing oat lines, and (ii) analyse the effect of line, environment and their interaction from the viewpoint of phenotypic plasticity. The experiment included 29 lines grown in the winter-rainfall region of South Australia. Grain traits included hectolitre weight, screenings, groat percentage, brightness and concentration of oil and protein. Hay traits, measured at GS71, included digestibility, crude protein, water soluble carbohydrates, acid detergent fibre, and neutral detergent fibre. High temperature, high vapour pressure deficit, and water deficit in the developmental window from GS31 to 200 °Cd after GS60 reduced hectolitre weight and groat percentage, and increased screenings. For hay, the proportion of water soluble carbohydrates declined, the proportion of both acid detergent fibre and neutral detergent fibre increased, and digestibility decreased with higher minimum temperature in a window from approx. −500 to +500 °Cd centred at anthesis. For both grain and hay, current lines returned high yield and high quality in favourable environments, where further improvement could focus on yield and maintenance of quality. In stressful environments, trade-offs between yield and quality were important; water soluble carbohydrates were the crux of these trade-offs. For grain, high concentration of water soluble carbohydrates favoured high hectolitre weight, low screenings and high groat percentage, at the expense of yield. For hay, high concentration of water soluble carbohydrates associated with higher digestibility and lower fibre, at the expense of yield. Nitrogen adds a layer of complexity to these relations, which were partially captured by leaf greenness measured with SPAD. Greener leaves associated with lower concentration of water soluble carbohydrates, hence capturing the established negative correlation between nitrogen and water soluble carbohydrates. Greener leaves associated positively with yield and protein concentration in grain and hay, lower digestibility and higher neutral (and acid) detergent fibre. Whereas the breeding program targets "specialist" phenotypes for grain and fodder, quality traits meeting market standards were spread across types. "Generalist" phenotypes can accommodate multiple agronomic uses but specialists are required where trade-offs are involved. [ABSTRACT FROM AUTHOR]

Summary: With the advent of rapid genotyping and next‐generation sequencing technologies, genome‐wide association study (GWAS) has become a routine strategy for decoding genotype–phenotype associations in many species. More than 1000 such studies over the last decade have revealed substantial genotype–phenotype associations in crops and provided unparalleled opportunities to probe functional genomics. Beyond the many 'hits' obtained, this review summarizes recent efforts to increase our understanding of the genetic architecture of complex traits by focusing on non‐main effects including epistasis, pleiotropy, and phenotypic plasticity. We also discuss how these achievements and the remaining gaps in our knowledge will guide future studies. Synthetic association is highlighted as leading to false causality, which is prevalent but largely underestimated. Furthermore, validation evidence is appealing for future GWAS, especially in the context of emerging genome‐editing technologies. Significance Statement: This review summarizes the latest advances in generating an overall view of the genetic architecture associated with crop complex traits, and discusses how these updated insights will guide future studies. A multiple‐causal‐allele hypothesis was formulated to explain the increasingly common artifact/synthetic associations. [ABSTRACT FROM AUTHOR]

Kernel moisture content at harvest stage (KMC) is an important factor affecting maize production, especially for mechanical harvesting. We investigated the genetic basis of KMC using an association panel comprising of 144 maize inbred lines that were phenotypically evaluated at two field trial locations. Significant positive or negative correlations were identified between KMC and a series of other agronomic traits, indicating that KMC is associated with other such traits. Combining phenotypic values and the Maize SNP3K Beadchip to perform a genome-wide association study revealed eight single nucleotide polymorphisms (SNPs) associated with KMC at P = 0.001 using a mixed linear model (PCA+K). These significant SNPs could be converted into five quantitative trait loci (QTLs) distributed on chromosomes 1, 5, 8, and 9. Of these QTLs, three were colocalized with genomic regions previously reported. Based on the phenotypic values of the alleles corresponding to significant SNPs, the favorable alleles were mined. Eight maize inbred lines with low KMC and harboring favorable alleles were identified. These QTLs and elite maize inbred lines with low KMC will be useful in maize breeding. [ABSTRACT FROM AUTHOR]

Grain number per panicle is a major component of rice yield that is typically controlled by many quantitative trait loci (QTLs). The identification of genes controlling grain number per panicle in rice would be valuable for the breeding of high-yielding rice. The Oryza glaberrima chromosome segment substitution line 9IL188 had significantly smaller panicles compared with the recurrent parent 9311. QTL analysis in an F2 population derived from a cross between 9IL188 and 9311 revealed that qgnp7(t), a major QTL located on the short arm of chromosome 7, was responsible for this phenotypic variation. Fine mapping was conducted using a large F3 population containing 2250 individuals that were derived from the F2 heterozygous plants. Additionally, plant height, panicle length, and grain number per panicle of the key F4 recombinant families were examined. Through two-step substitution mapping, qgnp7(t) was finally localized to a 41 kb interval in which eight annotated genes were identified according to available sequence annotation databases. Phenotypic evaluation of near isogenic lines (NIL-qgnp7 and NIL-qGNP7) indicated that qgnp7(t) has pleiotropic effects on rice plant architecture and panicle structure. In addition, yield estimation of NILs indicated that qGNP7(t) derived from 9311 is the favorable allele. Our results provide a foundation for isolating qgnp7(t). Markers flanking this QTL will be a useful tool for the marker-assisted selection of favorable alleles in O. glaberrima improvement programs. [ABSTRACT FROM AUTHOR]

Summary: Arbuscular mycorrhizal (AM) symbioses can improve plant tolerance to multiple stresses. We compared three AM fungi (AMF) from different genera, one of them isolated from a dry and saline environment, in terms of their ability to increase tomato tolerance to moderate or severe drought or salt stress. Plant physiological parameters and metabolic profiles were compared in order to find the molecular mechanisms underlying plant protection against stress.Mycorrhizal growth response was determined, and ultrahigh‐performance LC‐MS was used to compare the metabolic profile of plants under the different treatments.All AMF increased plant tolerance to stress, and the positive effects of the symbiosis were correlated with the severity of the stress. The AMF isolated from the stressful environment was the most effective in improving plant tolerance to salt stress. Differentially accumulated compounds were identified and the antistress properties of some of them were confirmed.We demonstrate that AM symbioses increase plant metabolic plasticity to cope with stress. Some responses were common to all AMF tested, while others were specifically related to particular isolates. Important metabolism reprograming was evidenced upon salt stress, and we identified metabolic pathways and compounds differentially accumulated in mycorrhizas that may underlie their enhanced tolerance to stress. [ABSTRACT FROM AUTHOR]

Highlights • Phenotypic plasticity is exceptionally high in A. adscensionis. • Survival in environmental heterogeneity is due to specific anatomical modifications. • Sclerification protects plants organs from collapse and desiccation. • Water conservation is a prime strategy in A. adscensionis for survival. Abstract Aristida adscensionis L. is a widely distributed grass species that particularly invades Potohar region (arid/semi-arid conditions) of the country. Exploration of adaptive components in this grass in relation to altitudinal gradient is the first attempt. Plant samples were collected from 6 different altitudinal ranges, viz. 400, 600, 800, 1000, 1200 and 1400 m a.s.l. Morpho-anatomical and physiological features along altitudinal gradient varied significantly that showed phenotypic plasticity in this species to inhabit a variety of environmental conditions. Stomata at 400 m altitude were larger and rhomboid-shaped, which changed to narrowly elliptic at moderate elevations and circular at high elevations. Growth and biomass production were maximum at 800–1000 m a.s.l. along with most of the morpho-anatomical and physiological features like proportion of vascular tissue, nutrient uptake, and chlorophyll pigments. Xeromorphy was high in plants colonisng at 1200 m elevations, which was indicated by an intensive sclerification, increased amount of storage parenchyma, increased vascular bundle number, deeply grooved bulliform cells, and dense pubescence on adaxial leaf surface. Leaf succulence was the unique feature in plants inhabiting 1400 m elevation. Another prominent feature was the development of chlorenchyma inner to stem epidermis. All these features reflect the tolerance capacity of A. adsecnsionis against environmental adversaries like salinity, aridity and low temperatures of the Potohar region. [ABSTRACT FROM AUTHOR]

Fruit size and shape are the primary criteria for domestication and improvement of tomato. The varying sizes and shapes of tomato fruit further signify their importance as agronomic traits. Here, we characterized a tomato mutant, smaller fruit (sf), which bears relatively small and ovoid fruits compared with the large and flat fruits of the wild-type (WT). Phenotypic measurements and histological analyses revealed that fruit diameter but not fruit length of the sf mutant decreased compared with that of the WT. This phenotypic change was attributed to significant decreases in locule number and pericarp cell layers in a transverse direction, which resulted in the transition of fruit shape from flat in the WT to ovoid in sf. Comparison of the transcriptomes of ovaries of sf with the WT using RNA-Seq identified 2596 differentially expressed genes, in which 1737 genes significantly were up-regulated and 859 genes were dramatically down-regulated in the sf ovary. Further analyses confirmed that some genes, such as CRCa, CNRs, CYCs, WUS, SUNs, OFRs, CDKs, participate in regulation of fruit size and shape of sf mutant. Thus, our study adds a new genetic resource regarding fruit size and shape of tomato, and provides a valuable basis for understanding molecular regulation of small and ovoid fruit of the sf mutant. [ABSTRACT FROM AUTHOR]

Lactic Acid Bacteria (LAB) are gram-positive, catalase-negative and non-spore forming bacteria known to have many advantages such as starter culture in food fermentation, as antimicrobial agent and plant growth promoter. Limited information on various LAB present in Malaysian fruits hampers further study to explore their potential as autochthonous inoculants in food fermentation, plant disease control and growth promotion. Therefore, the objectives of this study are firstly to isolate and identify LAB from honeydew, ciku, mango and mata kucing by investigating their morphological and biochemical characteristics, secondly to determine the identity of the isolates using 16S rRNA gene sequencing and finally to examine phylogenetic relationship of the LAB present in the fruits. The isolates were subjected to Gram staining, acidity and catalase tests, followed by molecular identification and phylogenetic analysis of the bacteria. Out of 33 isolates, eight isolates were gram-positive, catalase-negative and acid producers, suggesting that they are potentially LAB. 16S rRNA sequencing and NCBI Blast analysis identified the presence of Lactococcus sp., Leuconostoc sp., Weissella sp. and Aerococcus sp. in the fruit samples with sequence identity 94-97%. Phylogenetic tree was constructed based on the 16S rRNA sequences using Neighbor-Joining method. This study has assisted in collecting more information about the diversity of LAB in Malaysian fruits, which can be further explored in future for their application as bioinoculant in food fermentation or as biocontrol agent and plant growth promoter in agricultural field. [ABSTRACT FROM AUTHOR]

Abstract All creatures on earth are affected by their surrounding environment. Animals can move and escape unfavorable environmental changes, whereas plants must respond to environmental stimuli. Plants adapt to changes with cellular-level responses to short-term environmental changes, but may adapt to changes in the environment by regulating their development and growth. In this review, we considered changes in atmospheric CO 2 concentrations, dry/wet moisture conditions, flooding, and temperature as examples of environmental stimuli. We mainly focused on leaf morphology and stomatal density as examples of developmental and growth patterns of plants in response to the environment. [ABSTRACT FROM AUTHOR]

Abstract: Despite growing interest in incorporating intraspecific variation of functional traits in community‐level studies, it remains unclear whether species classified into functional groups based on interspecific trait differences are similar regarding their variation in trait expression in response to varying plant diversity and composition in local communities. In a large biodiversity experiment (Jena Experiment) designed on a trait‐based a priori definition of functional groups (grasses, legumes, small herbs, tall herbs), we studied means, extent of variation (coefficient of variation across communities) and plasticity to increased plant diversity (slopes over a logarithmic species richness ranging from 1, 2, 4, 8 and 16 to 60 species) for nine functional traits. Species means and extent of variation in traits related to nitrogen (N) acquisition and N use differed among functional groups and were more similar in phylogenetically closely related species than expected by chance. Species in the same functional group showed a weak phylogenetic signal and varied widely in means and extent of variation in traits related to shoot architecture and to a smaller extent in leaf traits related to carbon acquisition. This indicated that functional groups were less distinguishable in light than in nitrogen acquisition strategies. The direction and degree of trait plasticity to increasing species richness did not show a phylogenetic signal and were not different among functional groups, but varied largely among species within functional groups. Correlation structures in trait means, extent of trait variation and trait plasticity revealed functional tradeoffs in the acquisition of nitrogen and light across species. While correlations between trait means and extent of trait variation varied from trait to trait (positive, negative or unrelated), trait means and trait plasticity were mostly unrelated. Our results suggest that the concept of functional groups is viable, but context‐specific trait measurements are required to improve our understanding about the functional significance of intraspecific trait variation and interspecific trait differences in local plant communities. [ABSTRACT FROM AUTHOR]

Quantitative genetic analyses require extensive measurements of phenotypic traits, a task that is often not trivial, especially in wild populations. On top of instrumental measurement error, some traits may undergo transient (i.e., nonpersistent) fluctuations that are biologically irrelevant for selection processes. These two sources of variability, which we denote here as measurement error in a broad sense, are possible causes for bias in the estimation of quantitative genetic parameters. We illustrate how in a continuous trait transient effects with a classical measurement error structure may bias estimates of heritability, selection gradients, and the predicted response to selection. We propose strategies to obtain unbiased estimates with the help of repeated measurements taken at an appropriate temporal scale. However, the fact that in quantitative genetic analyses repeated measurements are also used to isolate permanent environmental instead of transient effects requires that the information content of repeated measurements is carefully assessed. To this end, we propose to distinguish "short‐term" from "long‐term" repeats, where the former capture transient variability and the latter help isolate permanent effects. We show how the inclusion of the corresponding variance components in quantitative genetic models yields unbiased estimates of all quantities of interest, and we illustrate the application of the method to data from a Swiss snow vole population. [ABSTRACT FROM AUTHOR]

The influences of maternal origins on plasticity of salt adaptability of Avicennia officinalis seedlings in the Sundarbans of Bangladesh were studied through use of a randomized block design. This study assayed different growth parameters, proline content, osmotic potential, and nutrients accumulation in different parts of A. officinalis seedlings of different maternal origins grown under different salinity regimes. Survival, chlorophyll, growth parameters, phenolic compounds, proline content, osmotic potential, nutrients (N, P, and K) and Na concentration in the roots, stems, bark, and leaves of A. officinalis seedlings originating from medium and high saline zones were higher at high salinities than those originating from low saline zone. Because of the previous exposure to high saline conditions during propagule maturation stage, seedlings of A. officinalis originating from medium and high saline zones adapted to greater salinity and thereby maintained satisfactory growth performance under high saline conditions than those from low saline zone. Thus, different maternal origins of A. officinalis brought about plasticity in salt adaptability which enabled this species to grow in a wide range of saline environments in the Sundarbans. This scientific knowledge will be useful for coastal afforestation and conservation of A. officinalis under increasing saline environments due to climate change. [ABSTRACT FROM AUTHOR]

Plants are thought to be able to regulate local root growth according to its overall nutrient status as well as nutrient contents in a local substrate patch. Therefore, root plastic responses to environmental changes are probably co-determined by local responses of root modules and systematic control of the whole plant. Recent studies showed that the contrast in nutrient availability between different patches could significantly influence the growth and death of local roots. In this study, we further explored, beside nutrient contrast, whether root growth and death in a local patch are also affected by relative root quantity in the patch. We conducted a split-root experiment with different splitting ratios of roots of Canada goldenrod (Solidago canadensis) individuals, as well as high- (5×Hoagland solution versus water) or low- (1ûHoagland solution versus water) contrast nutrient conditions for the split roots. The results showed that root growth decreased in nutrient-rich patches but increased in nutrient-poor patches when more roots co-occurred in the same patches, irrespective of nutrient contrast condition. Root mortality depended on contrasts in both root quantity and nutrients: in the high-nutrient-contrast condition, it increased in nutrientrich patches but decreased in nutrient-poor patches with increasing root proportion; while in the low-nutrient-contrast condition, it showed the opposite trend. These results demonstrated that root growth and death dynamics were affected by the contrast in both nutrient availability and root quantity between patches. Our study provided ecological evidence that local root growth and death are mediated by both the responses of root modules to a nutrient patch and the whole-plant nutrient status, suggesting that future work investigating root production and turnover should take into account the degree of heterogeneity in nutrient and root distribution. [ABSTRACT FROM AUTHOR]

Redox-associated events are important in plant development and responses to environmental stresses. In this study, we investigated spatial redox responses of cucumber ( Cucumis sativus L.) leaves to biotic stress ( Fusarium infection) or abiotic stress (water stress). Plants were grown under hydroponic conditions and either treated with polyethylene glycol to simulate drought or infected with Fusarium oxysporum f. sp. cucumerinum. Both water stress and Fusarium infection restricted cucumber growth and were associated with cellular plasma-membrane damage, reactive oxygen species accumulation, and changes in antioxidants; however, the responses to each stress were distinctive. Under water stress, H 2 O 2 generation at the leaf edge increased 29.7% compared with that at the centre but with Fusarium infection there was a relative 10.4% decrease at the edge. These changes correlated with changes in antioxidants and linked enzyme activities. The key sources of variation in oxidative events were defined by principal component analysis of all of the data and redox balance evaluations. We suggest that these spatial differences under water stress and Fusarium infection arise from discrete regulatory mechanisms, reflecting either developmental effect over the leaf regions or systemic anti-oxidative events occurred following infection. [ABSTRACT FROM AUTHOR]

Abstract: Key messageHistorical data generated during seed regeneration are valuable to populate a bio-digital resource center for barley (Hordeumsp.).Abstract: Precise estimates of trait performance of genetic resources are considered as an intellectually challenging, complex, costly and time-consuming step needed to exploit the phenotypic and genetic diversity maintained in genebanks for breeding and research. Using barley (Hordeum sp.) as a model, we examine strategies to tap into historical data available from regeneration trials. This is a first step toward extending the Federal ex situ Genebank into a bio-digital resource center facilitating an informed choice of barley accessions for research and breeding. Our study is based on historical data of seven decades collected for flowering time, plant height, and thousand grain weight during the regeneration of 12,872 spring and winter barley accessions. Linear mixed models were implemented in conjunction with routines for assessment of data quality. A resampling study highlights the potential risk of biased estimates in second-order statistics when grouping accessions for regeneration according to the year of collection or geographic origin. Based on rigorous quality assessment, we obtained high heritability estimates for the traits under consideration exceeding 0.8. Thus, the best linear unbiased estimations for the three traits are a valuable source to populate a bio-digital resource center for the IPK barley collection. The proposed strategy to leverage historical data from regeneration trials is not crop specific and can be used as a blueprint for other ex situ collections. [ABSTRACT FROM AUTHOR]

Abstract: Local adaptation and phenotypic plasticity are two important characteristics of alpine plants to overcome the threats caused by global changes. Among alpine species, Arabis alpina is characterised by an unusually wide altitudinal amplitude, ranging from 800 to 3,100 m of elevation in the French Alps. Two non‐exclusive hypotheses can explain the presence of A. alpina across this broad ecological gradient: adaptive phenotypic plasticity or local adaptation, making this species especially useful to better understand these phenomena in alpine plant species. We carried out common garden experiments at two different elevations with maternal progenies from six sites that differed in altitude. We showed that (1) key phenotypic traits (morphotype, total fruit length, growth, height) display significant signs of local adaptation, (2) most traits studied are characterised by a high phenotypic plasticity between the two experimental gardens and (3) the two populations from the highest elevations lacked morphological plasticity compared to the other populations. By combining two genome scan approaches (detection of selection and association methods), we isolated a candidate gene (Sucrose‐Phosphate Synthase 1). This gene was associated with height and local average temperature in our studied populations, consistent with previous studies on this gene in Arabidopsis thaliana. Synthesis. Given the nature of the traits involved in the detected pattern of local adaptation and the relative lack of plasticity of the two most extreme populations, our findings are consistent with a scenario of a locally adaptive stress response syndrome in high elevation populations. Due to a reduced phenotypic plasticity, an overall low intra‐population genetic diversity of the adaptive traits and weak gene flow, populations of high altitude might have difficulties to cope with, e.g. a rise of temperature. [ABSTRACT FROM AUTHOR]

Abstract: In temperate deciduous forests, understorey light environments vary dramatically throughout spring, summer and autumn due to tree canopy leaf display. This variability in light level is a physiological challenge for understorey species that produce sun‐adapted leaves in the spring before being shaded by the tree canopy. Similarly, some understorey species display leaves late into autumn after the tree canopy senesces. Many species in North American deciduous forests with extended leaf display are not native to North America. Since many non‐native species have been shown to have greater plasticity than natives, we hypothesized that leaves of non‐native species may be more plastic with respect to seasonal light changes than natives, and that this plasticity may allow them to assimilate more carbon in the same environment. We measured leaf traits and photosynthetic capacity of 17 native and 13 non‐native understorey shrub species in a common garden in Syracuse, New York, during spring, summer and autumn. We tested for the contribution of seasonal mean and variance (plasticity) of leaf traits to a species’ average photosynthetic rate and total leaf production. We also analysed the extent to which leaf adjustments depended on whether plants continued to produce new leaves over the growing season. Leaf traits of both native and non‐native species varied seasonally, but plasticity varied in extent and contribution to overall carbon gain. Non‐native species had the highest seasonal plasticity, but, contrary to our hypothesis, such plasticity did not contribute to their overall carbon gain. However, leaf trait plasticity was adaptive for native species that continued to produce leaves throughout the year, primarily due to increases in quantum efficiency and electron transport rate in leaves produced mid‐year compared to leaves produced early in the year. Synthesis. Despite large adjustments in leaf traits across seasonal light environments for both native species and non‐native species, we found little evidence that leaf‐level plasticity drives non‐native invasion or contributes strongly to annual carbon gain or productivity in understorey species. Instead, differences in mean leaf traits across seasons are sufficient to explain carbon gain advantages of non‐native woody species in deciduous forests. [ABSTRACT FROM AUTHOR]

Plants respond to environmental stimuli in a diversity of ways including the production of secondary metabolites. Biosynthesis of plant phenolics, including flavonoids, is frequently activated in response to a variety of abiotic and biotic stressors (e.g. extreme temperatures, high radiation, pathogens, etc.). This induced reaction is typically assumed to be a plastic response, but the components attributable to plasticity vs genetic variance in these components are poorly understood. Here, we investigate the variation in flavonoid production (anthocyanins and flavones) in petals and in photosynthetic tissues (calyces, leaves and stems) of Silene littorea . We performed a common garden experiment with maternal families from three populations in which plants were exposed to different light treatments (sun exposure and shade). The concentrations of anthocyanins in photosynthetic tissues increased when plants were exposed to sun, except for leaves that showed very low quantities of anthocyanins in both light treatments; yet flavones are produced constitutively in both sun and shade treatments. The synthesis of both anthocyanins and flavones is mostly plastic, with 25 to 43% of total phenotypic variance explained by light environment. We found significant environmental effects in anthocyanin biosynthesis in calyces and stems, and in flavone production in all photosynthetic tissues. Petals showed considerably less plasticity in anthocyanin production in contrast with the accumulation of these compounds in calyces and stems. Flavones exhibited less than half of the degree of phenotypic plasticity compared to anthocyanins in calyces and stems. Overall, these results provide new insights into the degree of tissue-specific plasticity and flavonoid-specific response. Variable plasticity between flavonoids types in petals and photosynthetic tissues may allow this annual plant to differentially respond to changing light environments, while maintaining constitutive petal color in response to pollinators. [ABSTRACT FROM AUTHOR]

Summary: Gene duplications and gene losses are major determinants of genome evolution and phenotypic diversity. The frequency of gene turnover (gene gains and gene losses combined) is known to vary between organisms. Comparative genomic analyses of gene families can highlight such variation; however, estimates of gene turnover may be biased when using highly fragmented genome assemblies resulting in poor gene annotations. Here, we address potential biases introduced by gene annotation errors in estimates of gene turnover frequencies in a dataset including both well‐annotated angiosperm genomes and the incomplete gene sets of four Pinaceae, including two pine species, Norway spruce and Douglas‐fir. We show that Pinaceae experienced higher gene turnover rates than angiosperm lineages lacking recent whole‐genome duplications. This finding is robust to both known major issues in Pinaceae gene sets: missing gene models and erroneous annotation of pseudogenes. A separate analysis limited to the four Pinaceae gene sets pointed to an accelerated gene turnover rate in pines compared with Norway spruce and Douglas‐fir. Our results indicate that gene turnover significantly contributes to genome variation and possibly to speciation in Pinaceae, particularly in pines. Moreover, these findings indicate that reliable estimates of gene turnover frequencies can be discerned in incomplete and potentially inaccurate gene sets. Because gymnosperms are known to exhibit low overall substitution rates compared with angiosperms, our results suggest that the rate of single‐base pair mutations is uncoupled from the rate of large DNA duplications and deletions associated with gene turnover in Pinaceae. [ABSTRACT FROM AUTHOR]

The widespread Mediterranean Pinus pinea showed exceptionally low genetic diversity and low differentiation between traits in the adult phase. We explored the adaptation potential of seedlings from four main Iberian provenances during their regeneration phase. We assessed the variability of shoot growth, allometry, physiological traits, and phenotypic plasticity to the interactive effect of light and water environments during 8-month moderate water-stress cycle and after one-week heat wave. The effect of shade and drought was mainly orthogonal whatever the provenance. The inland La Mancha provenance showed higher shoot growth and biomass compared to the southern coastal Depresión-del-Guadalquivir provenance. Following the heat wave, La Mancha presented higher net photosynthetic rates, a lower decrease in maximal quantum efficiency of PSII, and a higher accumulated relative height growth, thus, showing an adaptive advantage. The observed differences corroborated the ecological grouping of the provenances along latitudinal and inland-coastal gradients. We confirmed the high adaptive plasticity of Pinus pinea to the unpredictable Mediterranean environment. [ABSTRACT FROM AUTHOR]

1. Phenotypic plasticity is essential for the persistence of organisms under changing environmental conditions but the control of the relevant cellular mechanisms including which genes are involved and the regulation of those genes remains unclear. One way to address this issue is to evaluate links between gene expression, methylation and phenotype using transplantation and common garden experiments within genetically homogeneous populations. 2. This approach was taken using the Antarctic limpet Nacella concinna. In this species, two distinct phenotypes are associated with the intertidal and subtidal zones. The in situ gene expression and methylation profiles of intertidal and subtidal cohorts were directly compared before and after reciprocal transplantation as well as after a common garden acclimation to aquarium conditions for 9 months. 3. Expression profiles showed significant modulation of cellular metabolism to habitat zone with the intertidal profile characterised by transcription modules for antioxidant production, DNA repair and the cytoskeleton reflecting the need to cope with continually fluctuating and stressful conditions including wave action, UV irradiation and desiccation. 4. Transplantation had an effect on gene expression. The subtidal animals transplanted to the intertidal zone modified their gene expression patterns towards that of an intertidal profile. In contrast, many of the antioxidant genes were still differentially expressed in the intertidal animals several weeks after transplantation into the relatively benign subtidal zone. 5. Furthermore, a core of genes involved in antioxidation was still preferentially expressed in intertidal animals at the end of the common garden experiment. Thus, acclimation in an aquarium tank for 9 months did not completely erase the intertidal gene expression profile. 6. Significant methylation differences were measured between intertidal and subtidal animals from the wild and after transplantation, which were reduced on common garden acclimation. This suggests that epigenetic factors play an important role in physiological flexibility associated with environmental niche. [ABSTRACT FROM AUTHOR]

Background and Aims Understanding root traits and their trade-off with other plant processes is important for understanding plant functioning in natural ecosystems as well as agricultural systems. The aim of the present study was to determine the relationship between root morphology and the hydraulic characteristics of several orders of fine roots (<2 mm) for species differing in shade tolerance (low, moderate and high). Methods The morphological, anatomical and hydraulic traits across five distal root orders were measured in species with different levels of shade tolerance and life history strategies. The species studied were Acer negundo , Acer rubrum , Acer saccharum , Betula alleghaniensis , Betula lenta , Quercus alba , Quercus rubra , Pinus strobus and Pinus virginiana. Key Results Compared with shade-tolerant species, shade-intolerant species produced thinner absorptive roots with smaller xylem lumen diameters and underwent secondary development less frequently, suggesting that they had shorter life spans. Shade-tolerant species had greater root specific hydraulic conductance among these roots due to having larger diameter xylems, although these roots had a lower calculated critical tension for conduit collapse. In addition, shade-intolerant species exhibited greater variation in hydraulic conductance across different root growth rings in woody transport roots of the same root order as compared with shade-tolerant species. Conclusions Plant growth strategies were extended to include root hydraulic properties. It was found that shade intolerance in trees was associated with conservative root hydraulics but greater plasticity in number of xylem conduits and hydraulic conductance. Root traits of shade-intolerant species were consistent with the ability to proliferate roots quickly for rapid water uptake needed to support rapid shoot growth, while minimizing risk in uncertain environments. [ABSTRACT FROM AUTHOR]

Abstract: Ecological studies often assume that genetically similar individuals will be more similar in phenotypic traits, such that genetic diversity can serve as a proxy for trait diversity. Here, we explicitly test the relationship between genetic relatedness and trait distance using 40 eelgrass (Zostera marina) genotypes from five sites within Bodega Harbor, CA. We measured traits related to nutrient uptake, morphology, biomass and growth, photosynthesis, and chemical deterrents for all genotypes. We used these trait measurements to calculate a multivariate pairwise trait distance for all possible genotype combinations. We then estimated pairwise relatedness from 11 microsatellite markers. We found significant trait variation among genotypes for nearly every measured trait; however, there was no evidence of a significant correlation between pairwise genetic relatedness and multivariate trait distance among individuals. However, at the subpopulation level (sites within a harbor), genetic (FST) and trait differentiation were positively correlated. Our work suggests that pairwise relatedness estimated from neutral marker loci is a poor proxy for trait differentiation between individual genotypes. It remains to be seen whether genomewide measures of genetic differentiation or easily measured “master” traits (like body size) might provide good predictions of overall trait differentiation. [ABSTRACT FROM AUTHOR]

Abstract: The importance of phenotypic plasticity for successful invasion by exotic plant species has been well studied, but with contradictory and inconclusive results. However, many previous studies focused on comparisons of native and invasive species that co‐occur in a single invaded region, and thus on species with potentially very different evolutionary histories. We took a different approach by comparing three closely related Centaurea species: the highly invasive C. solstitialis, and the noninvasive but exotic C. calcitrapa and C. sulphurea. These species have overlapping distributions both in their native range of Spain and in their non‐native range of California. We collected seeds from 3 to 10 populations from each region and species and grew them in common garden greenhouse conditions to obtain an F1 generation in order to reduce maternal effects. Then, F1 seeds were grown subjected to simulated herbivory, variation in nutrient availability, and competition, to explore plasticity in the responses to these conditions. We found little variation in phenotypic plasticity among species and regions, but C. solstitialis plants from California produced more biomass in competition than their Spanish conspecifics. This species also had the highest relative growth rates when in competition and when grown under low nutrient availability. Noninvasive congeners produced intermediate or opposite patterns. [ABSTRACT FROM AUTHOR]