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Environmentally induced transgenerational plasticity can increase success of progeny and thereby be adaptive if progeny experiences the similarly parental environment. The ecological and evolutionary significance of transgenerational plasticity in plant has been studied mainly in the context of sexual generations. A pot experiment using the stoloniferous herb Centella asiatica was conducted to investigate the effects of high/low light treatment experienced by parental ramets (F 0 generation) on morphological and physiological properties of offspring ramets (F 2 generation) as well as growth performance. Light environment experienced by parental ramets (F 0 generation) significantly influenced petiole length, specific petiole length, internode length of stolon, leaf area, specific leaf area (SLA), leaf nitrogen and chlorophyll contents, potential maximum net photosynthetic rate ( P max ) in offspring ramets subjected to parental or non-parental environments even after they were detached from the parental ramets. Potential maximum net photosynthetic rate ( P max ) of offspring ramets (F 2 generation) from parental ramets (F 0 generation) subjected to low light treatment was significantly greater than that of offspring ramets (F 2 generation) from parental ramets (F 0 generation) subjected to high light treatment. Potential maximum net photosynthetic rate ( P max ) of offspring ramets (F 2 generation) subjected to parental light environment was greater than that of offspring ramets (F 2 generation) subjected to non-parental light environment. The greatest biomass accumulation and total stolon length were observed in offspring ramets (F 2 generation) subjected to low light treatment as parental ramets (F 0 generation) experienced. When parental ramets (F 0 generation) were subjected to low light treatment, biomass accumulation and total stolon length of offspring ramets (F 2 generation) experiencing parental light environment were significantly greater than those of offspring ramets (F 2 generation) experiencing non-parental light environment. Opposite pattern was observed in offspring ramets (F 2 generation) from parental ramets subjected to high light treatment. Our work provides evidence that transgenerational plasticity through both morphological and physiological flexibility was triggered across vegetative generations for stoloniferous herb C. asiatica subjected to high/low light treatment. The transgenerational plasticity can allow offspring ramets to present adaptive phenotype early without lag time in response to the current environment. Thus, it is very important for clonal plants in adapting temporally and spatially heterogeneous habitats.

The utility of plant functional traits for predictive ecology relies on our ability to interpret trait variation across multiple taxonomic and ecological scales. Using extensive data sets of trait variation within species, across species and across communities, we analysed whether and at what scales leaf economics spectrum (LES) traits show predicted trait-trait covariation. We found that most variation in LES traits is often, but not universally, at high taxonomic levels (between families or genera in a family). However, we found that trait covariation shows distinct taxonomic scale dependence, with some trait correlations showing opposite signs within vs. across species. LES traits responded independently to environmental gradients within species, with few shared environmental responses across traits or across scales. We conclude that, at small taxonomic scales, plasticity may obscure or reverse the broad evolutionary linkages between leaf traits, meaning that variation in LES traits cannot always be interpreted as differences in resource use strategy., (© 2018 John Wiley & Sons Ltd/CNRS.)

Leaf photosynthesis of crops acclimates to elevated CO 2 and temperature, but studies quantifying responses of leaf photosynthetic parameters to combined CO 2 and temperature increases under field conditions are scarce. We measured leaf photosynthesis of rice cultivars Changyou 5 and Nanjing 9108 grown in two free-air CO 2 enrichment (FACE) systems, respectively, installed in paddy fields. Each FACE system had four combinations of two levels of CO 2 (ambient and enriched) and two levels of canopy temperature (no warming and warmed by 1.0-2.0°C). Parameters of the C 3 photosynthesis model of Farquhar, von Caemmerer and Berry (the FvCB model), and of a stomatal conductance (g s ) model were estimated for the four conditions. Most photosynthetic parameters acclimated to elevated CO 2 , elevated temperature, and their combination. The combination of elevated CO 2 and temperature changed the functional relationships between biochemical parameters and leaf nitrogen content for Changyou 5. The g s model significantly underestimated g s under the combination of elevated CO 2 and temperature by 19% for Changyou 5 and by 10% for Nanjing 9108 if no acclimation was assumed. However, our further analysis applying the coupled g s -FvCB model to an independent, previously published FACE experiment showed that including such an acclimation response of g s hardly improved prediction of leaf photosynthesis under the four combinations of CO 2 and temperature. Therefore, the typical procedure that crop models using the FvCB and g s models are parameterized from plants grown under current ambient conditions may not result in critical errors in projecting productivity of paddy rice under future global change., (© 2017 John Wiley & Sons Ltd.)

Background and Aims: Despite the importance of growth [CO 2 ] and water availability for tree growth and survival, little information is available on how the interplay of these two factors can shape intraspecific patterns of functional variation in tree species, particularly for conifers. The main objective of the study was to test whether the range of realized drought tolerance within the species can be affected by elevated [CO 2 ]., Methods: Intraspecific variability in leaf gas exchange, growth rate and other leaf functional traits were studied in clones of maritime pine. A factorial experiment including water availability, growth [CO 2 ] and four different genotypes was conducted in growth rooms. A 'water deficit' treatment was imposed by applying a cycle of progressive soil water depletion and recovery at two levels of growth [CO 2 ]: 'ambient [CO 2 ]' (aCO 2 400 μmol mol -1 ) and 'elevated [CO 2 ]' (eCO 2 800 μmol mol -1 )., Key Results: eCO2 had a neutral effect on the impact of drought on growth and leaf gas exchange of the most drought-sensitive genotypes while it aggravated the impact of drought on the most drought-tolerant genotypes at aCO2. Thus, eCO2 attenuated genotypic differences in drought tolerance as compared with those observed at aCO2. Genotypic variation at both levels of growth [CO2] was found in specific leaf area and leaf nitrogen content but not in other physiological leaf traits such as intrinsic water use efficiency and leaf osmotic potential. eCO2 increased Δ 13 C but had no significant effect on δ 18 O. This effect did not interact with the impact of drought, which increased δ 18 O and decreased Δ 13 C. Nevertheless, correlations between Δ 13 C and δ 18 O indicated the non-stomatal component of water use efficiency in this species can be particularly sensitive to drought., Conclusions: Evidence from this study suggests elevated [CO 2 ] can modify current ranges of drought tolerance within tree species., (© The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com)

The high-yielding indica rice variety, 'Takanari', has the high rate of leaf photosynthesis compared with the commercial japonica varieties. Among backcrossed inbred lines from a cross between 'Takanari' and a japonica variety, 'Koshihikari', two lines, BTK-a and BTK-b, showed approximately 20% higher photosynthetic rate than that of 'Takanari' for a flag leaf at full heading. This is a highest recorded rate of rice leaf photosynthesis. Here, the timing and cause of the increased leaf photosynthesis in the BTK lines were investigated by examining the photosynthesis and related parameters, as well as mesophyll cell anatomy during ontogenesis. Their photosynthetic rate was greater than that of 'Takanari' in the 13th leaf, as well as the flag leaf, but there were no differences in the 7th and 10th leaves. There were no consistent differences in the stomatal conductance, or the leaf nitrogen and Rubisco contents in the 13th and flag leaves. The total surface area of mesophyll cells per leaf area (TA mes ) in the 13th and flag leaves increased significantly in the BTK lines due to the increased number and developed lobes of mesophyll cells compared with in 'Takanari'. The mesophyll conductance (g m ) became greater in the BTK lines compared with 'Takanari' in the flag leaves but not in the 10th leaves. A close correlation was observed between TA mes and g m . We concluded that the increased mesophyll conductance through the development of mesophyll cells during the reproductive period is a probable cause of the greater photosynthetic rate in the BTK lines.

Premise of the Study: Timing of budburst ( D BB ) may be related to the functional traits and distributions of woody species in temperate regions. Although many previous studies have investigated D BB in a number of temperate species, it has seldom been linked to multiple plant trait relationships., Methods: D BB and plant traits were investigated for 24 woody species for 2 years in a warm-temperate secondary forest in Japan. Particular attention was paid to differences in trait relationships between coexisting deciduous and evergreen broad-leaved species., Key Results: D BB was later for deciduous species with greater leaf mass, leaf area, vessel diameter, and leaf nitrogen content per unit mass. In addition, D BB was later for deciduous species with greater leaf mass, leaf area, vessel diameter, and leaf nitrogen content per unit mass. In addition, D BB was later for species with more northern distributions in deciduous and evergreen species., Conclusions: Clear differences in the trait relationships between deciduous and evergreen broad-leaved species might be caused by different selection pressures on D BB ; selection is expected to be more severe in deciduous species. Overall, the continuous variable of vessel diameter might be used as a simple and effective trait to predict D BB of deciduous species regardless of wood anatomy; however, no such traits were detected as effective predictors of D BB in evergreen species at this study site. In addition, D BB was earlier for the species of more southern distributions, suggesting that such species benefit more from warming., (© 2017 Botanical Society of America.)

Nitrogen (N) deposition has been increasing globally and has arisen concerns of its impacts on terrestrial ecosystems. Ecological indicators play an important role in ecosystem monitoring, assessment and management in the context of an anthropogenic transformation of the global N cycle. By integrating species composition and leaf N stoichiometry, a new community N indicator was defined and validated in the understory plots of an N enrichment (as NH 4 NO 3 ) experiment in an old-growth boreal forest in Northeast China. Three-year N additions showed no significant effect on the understory species richness, but an obvious shift in species composition occurred. The response of leaf N content to N additions was generally positive but varied by species. Overall, the community N indicator increased significantly with higher N addition level and soil available N content, being in the shape of a non-linear saturation response curve. The results suggest that the community N indicator could be an effective tool to indicate changes in ecosystem N availability. Critical values of the community N indicator for specific vegetation type could potentially provide useful information for nature conservation managers and policy makers., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Increasing the rate of leaf photosynthesis is one important approach for increasing grain yield in rice ( Oryza sativa ). Exploiting the natural variation in CO 2 assimilation rate ( A ) between rice cultivars using quantitative genetics is one promising means to identify genes contributing to higher photosynthesis. In this study, we determined precise location of Carbon Assimilation Rate 8 ( CAR8 ) by crossing a high-yielding indica cultivar with a Japanese commercial cultivar. Fine mapping suggested that CAR8 encodes a putative Heme Activator Protein 3 (OsHAP3) subunit of a CCAAT-box-binding transcription factor called OsHAP3H. Sequencing analysis revealed that the indica allele of CAR8 has a 1-bp deletion at 322 bp from the start codon, resulting in a truncated protein of 125 amino acids. In addition, CAR8 is identical to DTH8/Ghd8/LHD1 , which was reported to control rice flowering date. The increase of A is largely due to an increase of RuBP regeneration rate via increased leaf nitrogen content, and partially explained by reduced stomatal limitation via increased stomatal conductance relative to A . This allele also increases hydraulic conductivity, which would promote higher stomatal conductance. This indicates that CAR8 affects multiple physiological aspects relating to photosynthesis. The detailed analysis of molecular functions of CAR8 would help to understand the association between photosynthesis and flowering and demonstrate specific genetic mechanisms that can be exploited to improve photosynthesis in rice and potentially other crops.

Many exotic species have little apparent impact on ecosystem processes, whereas others have dramatic consequences for human and ecosystem health. There is growing evidence that invasions foster eutrophication. We need to identify species that are harmful and systems that are vulnerable to anticipate these consequences. Species' traits may provide the necessary insights. We conducted a global meta-analysis to determine whether plant leaf and litter functional traits, and particularly leaf and litter nitrogen (N) content and carbon: nitrogen (C : N) ratio, explain variation in invasive species' impacts on soil N cycling. Dissimilarity in leaf and litter traits among invaded and noninvaded plant communities control the magnitude and direction of invasion impacts on N cycling. Invasions that caused the greatest increases in soil inorganic N and mineralization rates had a much greater litter N content and lower litter C : N in the invaded than the reference community. Trait dissimilarities were better predictors than the trait values of invasive species alone. Quantifying baseline community tissue traits, in addition to those of the invasive species, is critical to understanding the impacts of invasion on soil N cycling., (© 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.)

We measured nitrogen stable isotope values (δ 15 N), and total phosphorus (%P) and total nitrogen (%N) contents in leaves of the temperate mangrove ( Avicennia marina sp. australasica ) from three coastal ecosystems exposed to various levels of human impact (Manukau, high; Mangawhai, low; and Waitemata, intermediate) in northern New Zealand. We measured δ 15 N values around 10‰ in environments where the major terrestrial water inputs are sewage. The highest average total nitrogen contents and δ 15 N values were found in the Auckland city region (Manukau Harbour) at 2.2%N and 9.9‰, respectively. The lowest values were found in Mangawhai Harbour, situated about 80 km north of Auckland city, at 2.0%N and 5.2‰, respectively. In the Waitemata Harbour, also located in Auckland city but with less exposure to human derived sewage inputs, both parameters were intermediate, at 2.1%N and 6.4‰. Total phosphorus contents did not vary significantly. Additionally, analysis of historical mangrove leaf herbarium samples obtained from the Auckland War Memorial Museum indicated that a reduction in both leaf total nitrogen and δ 15 N content has occurred over the past 100 years in Auckland's harbors. Collectively, these results suggest that anthropogenically derived nitrogen has had a significant impact on mangrove nutrient status in Auckland harbors over the last 100 years. The observed decrease in nitrogenous nutrients probably occurred due to sewage system improvements. We suggest that mangrove plant physiological response to nutrient excess could be used as an indicator of long-term eutrophication trends. Monitoring leaf nutrient status in mangroves can be used to assess environmental stress (sewage, eutrophication) on coastal ecosystems heavily impacted by human activities. Moreover, nitrogen and phosphorus leaf contents can be used to assess levels of available nutrients in the surrounding environments.