Excessive nitrogen application under moderate soil water deficit decreases photosynthesis, respiration, carbon gain and water use efficiency of maize

Background: Water use efficiency (WUE) is an important adaptive trait for soil water deficit. The molecular and physiological bases of WUE regulation in crops have been studied in detail in the context of plant breeding. Knowledge for most forest tree species lags behind, despite the need to identify populations or genotypes able to cope with the longer, more intense drought periods likely to result from climate warming. Results: We aimed to bridge this gap in knowledge for sessile oak (Quercus Petraeae Matt. L.), one of the most ecologically and economically important tree species in Europe, using a factorial design including two genotypes (low and high WUE) and two watering regimes (control and drought). By monitoring the ecophysiological response, we were able to identify groups of genotypes with high and low WUE. We then performed RNA-seq to quantify gene expression for the most extreme genotypes exposed to two watering regimes. By analyzing the interaction term, we were able to capture the molecular strategy of each group of plants for coping with drought. Regardless of water availability, the high WUE genotypes overexpressed genes associated with drought responses, and the control of stomatal density and distribution, and displayed a downregulation of genes associated with early stomatal closure and high transpiration rate. High-WUE genotypes, thus, coped with drought by fine-tuning the expression of genes with known functions in the regulation of stomatal size, density, movement or aperture and transpiration rate. Conclusion: Fine physiological screening of sessile oaks with contrasting WUE, and their molecular characterization i) highlighted subtle differences in transcription between low and high WUE genotypes, identifying key molecular players in the genetic control of this trait, and ii) revealed the genes underlying the molecular strategy that had evolved in each group to cope with water deficit, providing new insight into the value of WUE for adaptation to drought.

Download Full-text

Relationship between water use efficiency (WUE) and production of different wheat genotypes at soil water deficit

Colloids and Surfaces B Biointerfaces ◽

10.1016/j.colsurfb.2006.10.002 ◽

2006 ◽

Vol 53 (2) ◽

pp. 271-277 ◽

Cited By ~ 15

Author(s):

Ya-Chen Hu ◽

Hong-Bo Shao ◽

Li-Ye Chu ◽

Wu Gang

Keyword(s):

Water Use Efficiency ◽

Soil Water ◽

Water Deficit ◽

Water Use ◽

Soil Water Deficit ◽

Wheat Genotypes ◽

Use Efficiency

Download Full-text

Productivity and water use efficiency of sweet sorghum as affected by soil water deficit occurring at different vegetative growth stages

European Journal of Agronomy ◽

10.1016/s1161-0301(99)00032-5 ◽

1999 ◽

Vol 11 (3-4) ◽

pp. 207-215 ◽

Cited By ~ 64

Author(s):

Marcello Mastrorilli ◽

Nader Katerji ◽

Gianfranco Rana

Keyword(s):

Water Use Efficiency ◽

Soil Water ◽

Water Deficit ◽

Water Use ◽

Vegetative Growth ◽

Sweet Sorghum ◽

Growth Stages ◽

Soil Water Deficit ◽

Use Efficiency

Download Full-text

Understanding the genetic bases of adaptation to soil water deficit in trees through the examination of water use efficiency and cavitation resistance: maritime pine as a case study

Journal of Plant Hydraulics ◽

10.20870/jph.2016.e008 ◽

2016 ◽

Vol 3 ◽

pp. e008 ◽

Cited By ~ 10

Author(s):

Christophe Plomion ◽

Jérome Bartholomé ◽

Laurent Bouffier ◽

Oliver Brendel ◽

Hervé Cochard ◽

...

Keyword(s):

Water Use Efficiency ◽

Soil Water ◽

Water Deficit ◽

Water Use ◽

Maritime Pine ◽

Environment Interaction ◽

Soil Water Deficit ◽

Cavitation Resistance ◽

Use Efficiency ◽

Genetic Bases

This article provides a comprehensive view on the existing knowledge related to adaptation to soil water deficit in maritime pine, a conifer species widely planted in the southwestern Europe. It synthesizes discoveries made in ecophysiology, quantitative and population genetics as well as in genomics, combining several layers of information at the genotypic, phenotypic and environmental levels. Particular focus is given to two major traits: water-use efficiency (WUE) and cavitation resistance (CR). The former is related the maintenance of productivity during periods of lower soil water availability, whereas the latter is tightly linked to survival during severe drought. The development of high throughput phenotypic technologies have made it possible to estimate genetic and environmental variance components of these key traits, providing clues about their suitability for breeding and the evolutionary forces that have shaped their variability. Both CR and WUE were screened in different ecotypes as well as in the Aquitaine breeding population, the main genetic resource of the most advanced maritime pine breeding program in Europe.While the unexpectedly low level of variation of CR within and between natural populations will most likely hamper its use in breeding application, for WUE the medium heritability, absence of unfavorable phenotypic and genetic correlations with diameter growth, as well as the high inter-site correlation and weak genotype-by-environment interaction indicates that artificial selection could be applied for this trait without unfavorable consequences for radial growth, at least within the Aquitaine provenance. On the other hand, recent advances in sequencing and genotyping technologies have contributed to reveal the genetic architecture (i.e. number, location and effect of quantitative trait loci) of these two traits. In combination with ultra-dense genetic linkage map and functional genomics approaches, these findings will contribute to identify positional and expressional candidate genes that should be validated by association genetics and eventually introduced in genomic prediction models to make such knowledge useful to improve tree breeding.This review also opens up new research avenues and raises key questions on how to promote adaptation to the challenge of soil water deficit through genetic approaches in this species. If the results obtained so far in maritime pine can only applied to the tested genetic material, we however believe that the overall strategy presented here can be considered and cited as an example of integrative research to better understand the genetic bases of adaptation to soil water deficit in any forest tree species.

Download Full-text

Water Deficit Modulates the CO2 Fertilization Effect on Plant Gas Exchange and Leaf-Level Water Use Efficiency: A Meta-Analysis

Frontiers in Plant Science ◽

10.3389/fpls.2021.775477 ◽

2021 ◽

Vol 12 ◽

Author(s):

Fei Li ◽

Dagang Guo ◽

Xiaodong Gao ◽

Xining Zhao

Keyword(s):

Gas Exchange ◽

Water Use Efficiency ◽

Soil Water ◽

Water Deficit ◽

Water Use ◽

Future Climate Change ◽

Leaf Level ◽

Fertilization Effect ◽

Use Efficiency ◽

Stimulation Of

Elevated atmospheric CO2 concentrations ([eCO2]) and soil water deficits significantly influence gas exchange in plant leaves, affecting the carbon-water cycle in terrestrial ecosystems. However, it remains unclear how the soil water deficit modulates the plant CO2 fertilization effect, especially for gas exchange and leaf-level water use efficiency (WUE). Here, we synthesized a comprehensive dataset including 554 observations from 54 individual studies and quantified the responses for leaf gas exchange induced by e[CO2] under water deficit. Moreover, we investigated the contribution of plant net photosynthesis rate (Pn) and transpiration rates (Tr) toward WUE in water deficit conditions and e[CO2] using graphical vector analysis (GVA). In summary, e[CO2] significantly increased Pn and WUE by 11.9 and 29.3% under well-watered conditions, respectively, whereas the interaction of water deficit and e[CO2] slightly decreased Pn by 8.3%. Plants grown under light in an open environment were stimulated to a greater degree compared with plants grown under a lamp in a closed environment. Meanwhile, water deficit reduced Pn by 40.5 and 37.8%, while increasing WUE by 24.5 and 21.5% under ambient CO2 concentration (a[CO2]) and e[CO2], respectively. The e[CO2]-induced stimulation of WUE was attributed to the common effect of Pn and Tr, whereas a water deficit induced increase in WUE was linked to the decrease in Tr. These results suggested that water deficit lowered the stimulation of e[CO2] induced in plants. Therefore, fumigation conditions that closely mimic field conditions and multi-factorial experiments such as water availability are needed to predict the response of plants to future climate change.

Download Full-text