Graham Farquhar - Academia.edu (original) (raw)

Papers by Graham Farquhar

Research paper thumbnail of Correlation between Water‐Use Efficiency and Carbon Isotope Discrimination in Diverse Cowpea Genotypes and Isogenic Lines

Crop Science, 1992

Breeding cultivars with improved water use efficiency (WUE = total biomass production/water use) ... more Breeding cultivars with improved water use efficiency (WUE = total biomass production/water use) has been limited by the lack of suitable screening criteria. Theory has predicted an association between WUE and Δ (leaf discrimination against 13C) that could be used in indirect selection for WUE in C3 plants. Several studies have provided empirical evidence supporting this theory but with some exceptions. Earlier studies showed genotypic and drought‐induced variation in Δ in cowpea (Vigna unguiculata (L.) Walp.) and expected associations with leaf gas exchange for drought‐induced effects but not for genotypic effects. Studies were conducted to evaluate directly the association between seasonal WUE and Δ in cowpea. Five contrasting genotypes and two isogenic lines were grown in the field either in pots or under natural soil conditions and subjected to well‐watered or drought treatments. Genotypic rankings for Δ in leaves were consistent in the wet and dry pot and natural soil condition...

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Research paper thumbnail of Crop growth, water-use efficiency and carbon isotope discrimination in groundnut (Arachis hypogaea L.) genotypes under end-of season drought conditions

Annals of Applied Biology, Apr 1, 1993

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Research paper thumbnail of Carbon Isotope Fractionation and Plant Water-Use Efficiency

Springer eBooks, 1989

ABSTRACT

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Research paper thumbnail of Carbon Isotope Discrimination Varies Genetically in C<sub>4</sub> Species

Plant Physiology, Feb 1, 1990

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Research paper thumbnail of Physiological analysis of peanut cultivar response to timing and duration of drought stress

Australian journal of agricultural research, 1991

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Research paper thumbnail of Carbon Isotope Discrimination and Photosynthesis

Annual review of plant physiology and plant molecular biology, Jun 1, 1989

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Research paper thumbnail of Correlation between the Carbon Isotope Discrimination in Leaf Starch and Sugars of C<sub>3</sub> Plants and the Ratio of Intercellular and Atmospheric Partial Pressures of Carbon Dioxide

Plant Physiology, Dec 1, 1988

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Research paper thumbnail of Photosynthesis and gas exchange

Cambridge University Press eBooks, Oct 27, 1989

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Research paper thumbnail of Erratum: Vegetation effects on the isotope composition of oxygen in atmospheric C02

Nature, Sep 1, 1993

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Research paper thumbnail of A cross-scale analysis to understand and quantify effects of photosynthetic enhancement on crop growth and yield

Photosynthetic manipulation provides new opportunities for enhancing crop yield. However, underst... more Photosynthetic manipulation provides new opportunities for enhancing crop yield. However, understanding and quantifying effectively how the seasonal growth and yield dynamics of target crops might be affected over a wide range of environments is limited. Using a state-of-the-art cross-scale model we predicted crop-level impacts of a broad list of promising photosynthesis manipulation strategies for C3 wheat and C4 sorghum. The manipulation targets have varying effects on the enzyme-limited (Ac) and electron transport-limited (Aj) rates of photosynthesis. In the top decile of seasonal outcomes, yield gains with the list of manipulations were predicted to be modest, ranging between 0 and 8%, depending on the crop type and manipulation. To achieve the higher yield gains, large increases in both Ac and Aj are needed. This could likely be achieved by stacking Rubisco function and electron transport chain enhancements or installing a full CO2 concentrating system. However, photosynthetic ...

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Research paper thumbnail of Revisiting carbon isotope discrimination in C3 plants shows respiration rules when photosynthesis is low

Nature Plants, 2020

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Research paper thumbnail of Stomatal conductance responses to evaporative demand conferred by rice drought-yield quantitative trait locus qDTY12.1

Functional Plant Biology, 2019

Rice quantitative trait locus (QTL) qDTY12.1 is a major-effect drought yield QTL that was identif... more Rice quantitative trait locus (QTL) qDTY12.1 is a major-effect drought yield QTL that was identified from a cross of Vandana (recipient parent) and Way Rarem (donor parent) through breeding efforts to improve rice yield under upland drought stress conditions. The two main physiological effects previously observed to be related to the presence of qDTY12.1 were (i) increased lateral root growth, and (ii) increased transpiration efficiency. Since relatively more progress has thus far been made on characterising the lateral root growth response related to qDTY12.1, the present study focussed on characterising how qDTY12.1 confers higher transpiration efficiency under upland drought stress in the Vandana background. In a series of field experiments in which stomatal conductance was measured across different times of day in four qDTY12.1 near isogenic lines (NILs), the NILs and Way Rarem showed consistently higher stomatal conductance than Vandana under conditions of low vapour pressure d...

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Research paper thumbnail of Simulating daily field crop canopy photosynthesis: an integrated software package

Functional Plant Biology, 2018

Photosynthetic manipulation is seen as a promising avenue for advancing field crop productivity. ... more Photosynthetic manipulation is seen as a promising avenue for advancing field crop productivity. However, progress is constrained by the lack of connection between leaf-level photosynthetic manipulation and crop performance. Here we report on the development of a model of diurnal canopy photosynthesis for well watered conditions by using biochemical models of C3 and C4 photosynthesis upscaled to the canopy level using the simple and robust sun–shade leaves representation of the canopy. The canopy model was integrated over the time course of the day for diurnal canopy photosynthesis simulation. Rationality analysis of the model showed that it simulated the expected responses in diurnal canopy photosynthesis and daily biomass accumulation to key environmental factors (i.e. radiation, temperature and CO2), canopy attributes (e.g. leaf area index and leaf angle) and canopy nitrogen status (i.e. specific leaf nitrogen and its profile through the canopy). This Diurnal Canopy Photosynthesi...

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Research paper thumbnail of CO2 and Water Vapor Exchange across Leaf Cuticle (Epidermis) at Various Water Potentials

Plant Physiology, 1997

Cuticular properties affect the gas exchange of leaves, but little is known about how much CO2 an... more Cuticular properties affect the gas exchange of leaves, but little is known about how much CO2 and water vapor cross the cuticular barrier or whether low water potentials affect the process. Therefore, we measured the cuticular conductances for CO2 and water vapor in grape (Vitis vinifera L.) leaves having various water potentials. The lower leaf surface was sealed to force all gas exchange through the upper surface, which was stoma-free. In this condition both gases passed through the cuticle, and the CO2 conductance could be directly determined from the internal mole fraction of CO2 near the compensation point, the external mole fraction of CO2, and the CO2 flux. The cuticle allowed small amounts of CO2 and water vapor to pass through, indicating that gas exchange occurs in grape leaves no matter how tightly the stomata are closed. However, the CO2 conductance was only 5.7% of that for water vapor. This discrimination against CO2 markedly affected calculations of the mole fraction...

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Research paper thumbnail of Global variability in leaf respiration in relation to climate, plant functional types and leaf traits

New Phytologist, 2015

Summary Leaf dark respiration (Rdark) is an important yet poorly quantified component of the glob... more Summary Leaf dark respiration (Rdark) is an important yet poorly quantified component of the global carbon cycle. Given this, we analyzed a new global database of Rdark and associated leaf traits. Data for 899 species were compiled from 100 sites (from the Arctic to the tropics). Several woody and nonwoody plant functional types (PFTs) were represented. Mixed‐effects models were used to disentangle sources of variation in Rdark. Area‐based Rdark at the prevailing average daily growth temperature (T) of each site increased only twofold from the Arctic to the tropics, despite a 20°C increase in growing T (8–28°C). By contrast, Rdark at a standard T (25°C, Rdark25) was threefold higher in the Arctic than in the tropics, and twofold higher at arid than at mesic sites. Species and PFTs at cold sites exhibited higher Rdark25 at a given photosynthetic capacity (Vcmax25) or leaf nitrogen concentration ([N]) than species at warmer sites. Rdark25 values at any given Vcmax25 or [N] were higher...

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Research paper thumbnail of Genetic Variation in the Relationship between Photosynthetic CO2 Assimilation Rate and Stomatal Conductance to Water Loss

Progress in Photosynthesis Research, 1987

Jones (1) has discussed two main reasons for attempting to manipulate stornata by breeding. The f... more Jones (1) has discussed two main reasons for attempting to manipulate stornata by breeding. The first was to maximise productivity and hence yield, by increasing rates of assimilation of CO2. An increase in stomatal conductance would be expected to achieve this in C3 species by increasing the partial pressure of CO2 within the leaf, p., which would be useful in conditions where water supply is not limiting. The second was to improve drought tolerance. A decreased stomatal conductance can aid in this direction, but at some expense to yield potential (yield in well-watered conditions).

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Research paper thumbnail of Genetic and Environmental Variation in Transpiration Efficiency and Its Correlation with Carbon Isotope Discrimination and Specific Leaf Area in Peanut

Elsevier eBooks, 1993

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Research paper thumbnail of Ralph Owen Slatyer 1929–2012

Historical Records of Australian Science, 2020

Ralph Slatyer (16 April 1929–26 July 2012) had a distinguished career in the Commonwealth Scienti... more Ralph Slatyer (16 April 1929–26 July 2012) had a distinguished career in the Commonwealth Scientific and Industrial Research Organisation and the Australian National University, in plant-water relations and plant succession, leading the development of physiological plant ecology. He was the founding Professor of Environmental Biology at the Research School of Biological Sciences, at the Australian National University and then Director of the Research School of Biological Sciences, 1984–9. He was Australian Ambassador to United Nations Educational and Scientific Cultural Organisation (1978–81), and as Australia’s first Chief Scientist (1989–92), he set up the Cooperative Research Centres.

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Research paper thumbnail of Author Correction: An improved theory for calculating leaf gas exchange more precisely accounting for small fluxes

Nature Plants, 2021

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Research paper thumbnail of Optimization can provide the fundamental link between leaf photosynthesis, gas exchange and water relations

Nature Plants, 2020

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Research paper thumbnail of Correlation between Water‐Use Efficiency and Carbon Isotope Discrimination in Diverse Cowpea Genotypes and Isogenic Lines

Crop Science, 1992

Breeding cultivars with improved water use efficiency (WUE = total biomass production/water use) ... more Breeding cultivars with improved water use efficiency (WUE = total biomass production/water use) has been limited by the lack of suitable screening criteria. Theory has predicted an association between WUE and Δ (leaf discrimination against 13C) that could be used in indirect selection for WUE in C3 plants. Several studies have provided empirical evidence supporting this theory but with some exceptions. Earlier studies showed genotypic and drought‐induced variation in Δ in cowpea (Vigna unguiculata (L.) Walp.) and expected associations with leaf gas exchange for drought‐induced effects but not for genotypic effects. Studies were conducted to evaluate directly the association between seasonal WUE and Δ in cowpea. Five contrasting genotypes and two isogenic lines were grown in the field either in pots or under natural soil conditions and subjected to well‐watered or drought treatments. Genotypic rankings for Δ in leaves were consistent in the wet and dry pot and natural soil condition...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Crop growth, water-use efficiency and carbon isotope discrimination in groundnut (Arachis hypogaea L.) genotypes under end-of season drought conditions

Annals of Applied Biology, Apr 1, 1993

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Carbon Isotope Fractionation and Plant Water-Use Efficiency

Springer eBooks, 1989

ABSTRACT

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Carbon Isotope Discrimination Varies Genetically in C<sub>4</sub> Species

Plant Physiology, Feb 1, 1990

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Physiological analysis of peanut cultivar response to timing and duration of drought stress

Australian journal of agricultural research, 1991

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Carbon Isotope Discrimination and Photosynthesis

Annual review of plant physiology and plant molecular biology, Jun 1, 1989

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Correlation between the Carbon Isotope Discrimination in Leaf Starch and Sugars of C<sub>3</sub> Plants and the Ratio of Intercellular and Atmospheric Partial Pressures of Carbon Dioxide

Plant Physiology, Dec 1, 1988

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Photosynthesis and gas exchange

Cambridge University Press eBooks, Oct 27, 1989

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Erratum: Vegetation effects on the isotope composition of oxygen in atmospheric C02

Nature, Sep 1, 1993

Bookmarks Related papers MentionsView impact

Research paper thumbnail of A cross-scale analysis to understand and quantify effects of photosynthetic enhancement on crop growth and yield

Photosynthetic manipulation provides new opportunities for enhancing crop yield. However, underst... more Photosynthetic manipulation provides new opportunities for enhancing crop yield. However, understanding and quantifying effectively how the seasonal growth and yield dynamics of target crops might be affected over a wide range of environments is limited. Using a state-of-the-art cross-scale model we predicted crop-level impacts of a broad list of promising photosynthesis manipulation strategies for C3 wheat and C4 sorghum. The manipulation targets have varying effects on the enzyme-limited (Ac) and electron transport-limited (Aj) rates of photosynthesis. In the top decile of seasonal outcomes, yield gains with the list of manipulations were predicted to be modest, ranging between 0 and 8%, depending on the crop type and manipulation. To achieve the higher yield gains, large increases in both Ac and Aj are needed. This could likely be achieved by stacking Rubisco function and electron transport chain enhancements or installing a full CO2 concentrating system. However, photosynthetic ...

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Research paper thumbnail of Revisiting carbon isotope discrimination in C3 plants shows respiration rules when photosynthesis is low

Nature Plants, 2020

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Research paper thumbnail of Stomatal conductance responses to evaporative demand conferred by rice drought-yield quantitative trait locus qDTY12.1

Functional Plant Biology, 2019

Rice quantitative trait locus (QTL) qDTY12.1 is a major-effect drought yield QTL that was identif... more Rice quantitative trait locus (QTL) qDTY12.1 is a major-effect drought yield QTL that was identified from a cross of Vandana (recipient parent) and Way Rarem (donor parent) through breeding efforts to improve rice yield under upland drought stress conditions. The two main physiological effects previously observed to be related to the presence of qDTY12.1 were (i) increased lateral root growth, and (ii) increased transpiration efficiency. Since relatively more progress has thus far been made on characterising the lateral root growth response related to qDTY12.1, the present study focussed on characterising how qDTY12.1 confers higher transpiration efficiency under upland drought stress in the Vandana background. In a series of field experiments in which stomatal conductance was measured across different times of day in four qDTY12.1 near isogenic lines (NILs), the NILs and Way Rarem showed consistently higher stomatal conductance than Vandana under conditions of low vapour pressure d...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Simulating daily field crop canopy photosynthesis: an integrated software package

Functional Plant Biology, 2018

Photosynthetic manipulation is seen as a promising avenue for advancing field crop productivity. ... more Photosynthetic manipulation is seen as a promising avenue for advancing field crop productivity. However, progress is constrained by the lack of connection between leaf-level photosynthetic manipulation and crop performance. Here we report on the development of a model of diurnal canopy photosynthesis for well watered conditions by using biochemical models of C3 and C4 photosynthesis upscaled to the canopy level using the simple and robust sun–shade leaves representation of the canopy. The canopy model was integrated over the time course of the day for diurnal canopy photosynthesis simulation. Rationality analysis of the model showed that it simulated the expected responses in diurnal canopy photosynthesis and daily biomass accumulation to key environmental factors (i.e. radiation, temperature and CO2), canopy attributes (e.g. leaf area index and leaf angle) and canopy nitrogen status (i.e. specific leaf nitrogen and its profile through the canopy). This Diurnal Canopy Photosynthesi...

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Research paper thumbnail of CO2 and Water Vapor Exchange across Leaf Cuticle (Epidermis) at Various Water Potentials

Plant Physiology, 1997

Cuticular properties affect the gas exchange of leaves, but little is known about how much CO2 an... more Cuticular properties affect the gas exchange of leaves, but little is known about how much CO2 and water vapor cross the cuticular barrier or whether low water potentials affect the process. Therefore, we measured the cuticular conductances for CO2 and water vapor in grape (Vitis vinifera L.) leaves having various water potentials. The lower leaf surface was sealed to force all gas exchange through the upper surface, which was stoma-free. In this condition both gases passed through the cuticle, and the CO2 conductance could be directly determined from the internal mole fraction of CO2 near the compensation point, the external mole fraction of CO2, and the CO2 flux. The cuticle allowed small amounts of CO2 and water vapor to pass through, indicating that gas exchange occurs in grape leaves no matter how tightly the stomata are closed. However, the CO2 conductance was only 5.7% of that for water vapor. This discrimination against CO2 markedly affected calculations of the mole fraction...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Global variability in leaf respiration in relation to climate, plant functional types and leaf traits

New Phytologist, 2015

Summary Leaf dark respiration (Rdark) is an important yet poorly quantified component of the glob... more Summary Leaf dark respiration (Rdark) is an important yet poorly quantified component of the global carbon cycle. Given this, we analyzed a new global database of Rdark and associated leaf traits. Data for 899 species were compiled from 100 sites (from the Arctic to the tropics). Several woody and nonwoody plant functional types (PFTs) were represented. Mixed‐effects models were used to disentangle sources of variation in Rdark. Area‐based Rdark at the prevailing average daily growth temperature (T) of each site increased only twofold from the Arctic to the tropics, despite a 20°C increase in growing T (8–28°C). By contrast, Rdark at a standard T (25°C, Rdark25) was threefold higher in the Arctic than in the tropics, and twofold higher at arid than at mesic sites. Species and PFTs at cold sites exhibited higher Rdark25 at a given photosynthetic capacity (Vcmax25) or leaf nitrogen concentration ([N]) than species at warmer sites. Rdark25 values at any given Vcmax25 or [N] were higher...

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Research paper thumbnail of Genetic Variation in the Relationship between Photosynthetic CO2 Assimilation Rate and Stomatal Conductance to Water Loss

Progress in Photosynthesis Research, 1987

Jones (1) has discussed two main reasons for attempting to manipulate stornata by breeding. The f... more Jones (1) has discussed two main reasons for attempting to manipulate stornata by breeding. The first was to maximise productivity and hence yield, by increasing rates of assimilation of CO2. An increase in stomatal conductance would be expected to achieve this in C3 species by increasing the partial pressure of CO2 within the leaf, p., which would be useful in conditions where water supply is not limiting. The second was to improve drought tolerance. A decreased stomatal conductance can aid in this direction, but at some expense to yield potential (yield in well-watered conditions).

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Genetic and Environmental Variation in Transpiration Efficiency and Its Correlation with Carbon Isotope Discrimination and Specific Leaf Area in Peanut

Elsevier eBooks, 1993

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Ralph Owen Slatyer 1929–2012

Historical Records of Australian Science, 2020

Ralph Slatyer (16 April 1929–26 July 2012) had a distinguished career in the Commonwealth Scienti... more Ralph Slatyer (16 April 1929–26 July 2012) had a distinguished career in the Commonwealth Scientific and Industrial Research Organisation and the Australian National University, in plant-water relations and plant succession, leading the development of physiological plant ecology. He was the founding Professor of Environmental Biology at the Research School of Biological Sciences, at the Australian National University and then Director of the Research School of Biological Sciences, 1984–9. He was Australian Ambassador to United Nations Educational and Scientific Cultural Organisation (1978–81), and as Australia’s first Chief Scientist (1989–92), he set up the Cooperative Research Centres.

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Research paper thumbnail of Author Correction: An improved theory for calculating leaf gas exchange more precisely accounting for small fluxes

Nature Plants, 2021

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Optimization can provide the fundamental link between leaf photosynthesis, gas exchange and water relations

Nature Plants, 2020

Bookmarks Related papers MentionsView impact