The Experts below are selected from a list of 2421 Experts worldwide ranked by ideXlab platform

Catherine Picon-cochard - One of the best experts on this subject based on the ideXlab platform.

  • The resilience of perennial grasses under two climate scenarios is correlated with carbohydrate metabolism in Meristems
    Journal of Experimental Botany, 2020
    Co-Authors: Florence Volaire, Annette Morvan-bertrand, Marie-pascale Prud’homme, Marie-lise Benot, Angela Augusti, Marine Zwicke, Jacques Roy, Damien Landais, Catherine Picon-cochard
    Abstract:

    Extreme climatic events (ECEs) such as droughts and heat waves affect ecosystem functioning and species turnover. This study investigated the effect of elevated CO2 on species' resilience to ECEs. Monoliths of intact soil and their plant communities from an upland grassland were exposed to 2050 climate scenarios with or without an ECE under ambient (390 ppm) or elevated (520 ppm) CO2 . Ecophysiological traits of two perennial grasses (Dactylis glomerate and Holcus lanatus) were measured before, during, and after ECE. At similar soil water content, Leaf elongation was greater under elevated CO2 for both species. The resilience of D. glomerate increased under enhanced CO2 (+60%) whereas H. lanatus mostly died during ECE. D. glomerate accumulated 30% more fructans, which were more highly polymerized, and 4-fold less sucrose than H. lanatus. The fructan concentration in Leaf Meristems was significantly increased under elevated CO2. Their relative abundance changed during the ECE, resulting in a more polymerized assemblage in H. lanatus and a more depolymerized assemblage in D. glomerate. The ratio of low degree of polymerization fructans to sucrose in Leaf Meristems was the best predictor of resilience across species. This study underlines the role of carbohydrate metabolism and the species-dependent effect of elevated CO2 on the resilience of grasses to ECE.

Xiaodan Wang - One of the best experts on this subject based on the ideXlab platform.

  • Leaf Meristems an easily ignored component of the response to human disturbance in alpine grasslands
    Ecology and Evolution, 2016
    Co-Authors: Jiangtao Hong, Xiaodan Wang
    Abstract:

    Grazing and fencing are two important factors that influence productivity and biomass allocation in alpine grasslands. The relationship between root (R) and shoot (S) biomass and the root: shoot ratio (R/S) are critical parameters for estimating the terrestrial carbon stocks and biomass allocation mechanism responses to human activities. Previous studies have often used the belowground: aboveground biomass ratio (M-b/M-a) to replace the R/S in alpine ecosystems. However, these studies may have neglected the Leaf meristem biomass, which belongs to the shoot but occurs below the soil surface, leading to a significant overestimation of the R/S ratio. We conducted a comparative study to explore the differences between the R/S and M-b/M-a at both the species (Stipa purpurea, Carex moorcroftii, and Artemisia nanschanica) and community levels on a Tibetan alpine grassland with grazing and fencing management blocks. The results revealed that the use of the M-b/M-a to express the R/S appeared to overestimate the actual value of the R/S, both at species and community levels. For S. purpurea, the M-b/M-a was three times higher than the R/S. The M-b/M-a was approximately two times higher than the R/S for the species of C. moorcroftii and A. nanschanica and at the community level. The relationships between the R-S and M-b-M-a exhibited different slopes for the alpine plants across all the management practices. Compared to the fenced grasslands, the plants in the grazing blocks not only allocated more biomass to the roots but also to the Leaf Meristems. The present study highlights the contribution of Leaf Meristems to the accurate assessment of shoot and belowground biomasses. The R/S and M-b/M-a should be cautiously used in combination in the future research. The understanding of the distinction between the R-S and M-b-M-a may help to improve the biomass allocation mechanism response to human disturbances in an alpine area.

Florence Volaire - One of the best experts on this subject based on the ideXlab platform.

  • The resilience of perennial grasses under two climate scenarios is correlated with carbohydrate metabolism in Meristems
    Journal of Experimental Botany, 2020
    Co-Authors: Florence Volaire, Annette Morvan-bertrand, Marie-pascale Prud’homme, Marie-lise Benot, Angela Augusti, Marine Zwicke, Jacques Roy, Damien Landais, Catherine Picon-cochard
    Abstract:

    Extreme climatic events (ECEs) such as droughts and heat waves affect ecosystem functioning and species turnover. This study investigated the effect of elevated CO2 on species' resilience to ECEs. Monoliths of intact soil and their plant communities from an upland grassland were exposed to 2050 climate scenarios with or without an ECE under ambient (390 ppm) or elevated (520 ppm) CO2 . Ecophysiological traits of two perennial grasses (Dactylis glomerate and Holcus lanatus) were measured before, during, and after ECE. At similar soil water content, Leaf elongation was greater under elevated CO2 for both species. The resilience of D. glomerate increased under enhanced CO2 (+60%) whereas H. lanatus mostly died during ECE. D. glomerate accumulated 30% more fructans, which were more highly polymerized, and 4-fold less sucrose than H. lanatus. The fructan concentration in Leaf Meristems was significantly increased under elevated CO2. Their relative abundance changed during the ECE, resulting in a more polymerized assemblage in H. lanatus and a more depolymerized assemblage in D. glomerate. The ratio of low degree of polymerization fructans to sucrose in Leaf Meristems was the best predictor of resilience across species. This study underlines the role of carbohydrate metabolism and the species-dependent effect of elevated CO2 on the resilience of grasses to ECE.

Jiangtao Hong - One of the best experts on this subject based on the ideXlab platform.

  • Leaf Meristems an easily ignored component of the response to human disturbance in alpine grasslands
    Ecology and Evolution, 2016
    Co-Authors: Jiangtao Hong, Xiaodan Wang
    Abstract:

    Grazing and fencing are two important factors that influence productivity and biomass allocation in alpine grasslands. The relationship between root (R) and shoot (S) biomass and the root: shoot ratio (R/S) are critical parameters for estimating the terrestrial carbon stocks and biomass allocation mechanism responses to human activities. Previous studies have often used the belowground: aboveground biomass ratio (M-b/M-a) to replace the R/S in alpine ecosystems. However, these studies may have neglected the Leaf meristem biomass, which belongs to the shoot but occurs below the soil surface, leading to a significant overestimation of the R/S ratio. We conducted a comparative study to explore the differences between the R/S and M-b/M-a at both the species (Stipa purpurea, Carex moorcroftii, and Artemisia nanschanica) and community levels on a Tibetan alpine grassland with grazing and fencing management blocks. The results revealed that the use of the M-b/M-a to express the R/S appeared to overestimate the actual value of the R/S, both at species and community levels. For S. purpurea, the M-b/M-a was three times higher than the R/S. The M-b/M-a was approximately two times higher than the R/S for the species of C. moorcroftii and A. nanschanica and at the community level. The relationships between the R-S and M-b-M-a exhibited different slopes for the alpine plants across all the management practices. Compared to the fenced grasslands, the plants in the grazing blocks not only allocated more biomass to the roots but also to the Leaf Meristems. The present study highlights the contribution of Leaf Meristems to the accurate assessment of shoot and belowground biomasses. The R/S and M-b/M-a should be cautiously used in combination in the future research. The understanding of the distinction between the R-S and M-b-M-a may help to improve the biomass allocation mechanism response to human disturbances in an alpine area.

Hirokazu Tsukaya - One of the best experts on this subject based on the ideXlab platform.

  • behavior of Leaf Meristems and their modification
    Frontiers in Plant Science, 2015
    Co-Authors: Yasunori Ichihashi, Hirokazu Tsukaya
    Abstract:

    A major source of diversity in flowering plant form is the extensive variability of Leaf shape and size. Leaf formation is initiated by recruitment of a handful of cells flanking the shoot apical meristem (SAM) to develop into a complex three-dimensional structure. Leaf organogenesis depends on activities of several distinct Meristems that are established and spatiotemporally differentiated after the initiation of Leaf primordia. Here, we review recent findings in the gene regulatory networks that orchestrate Leaf meristem activities in a model plant Arabidopsis thaliana. We then discuss recent key studies investigating the natural variation in Leaf morphology to understand how the gene regulatory networks modulate Leaf Meristems to yield a substantial diversity of Leaf forms during the course of evolution.