Genetic Variation in Carbon Isotope Discrimination and Its Relation to Stomatal Conductance in Pima Cotton (Gossypium barbadense)

1996 ◽  
Vol 23 (2) ◽  
pp. 127 ◽  
Author(s):  
Zhenmin Lu ◽  
Jiwei Chen ◽  
RG Percy ◽  
MR Sharifi ◽  
PW Rundel ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Stomatal Conductance ◽  
Heat Resistance ◽  
Carbon Isotope ◽  
Carbon Isotope Discrimination ◽  
Stable Carbon Isotope ◽  
Gossypium Barbadense ◽  
High Irradiance ◽  
Isotope Discrimination ◽  
Selection For

Stable carbon isotope discrimination (Δ) was evaluated in primitive and cultivated Gossypium barbadense L. Significant differences among cultivated Pima lines were positively associated with the degree of selection for lint yield and heat resistance. A population mean study of a cross between B368, a primitive, uncultivated G. barbadense, and Pima S-6, an advanced line, showed that Δ is probably under genetic control, and could be a suitable selection trait in breeding programs. Eleven uncultivated accessions of primitive G. barbadense of varying origins grown in one environment showed a broad range of Δ values (18.8-20.50), pointing to substantial genetic variation of Δ in the G. barbadense germplasm. A was strongly correlated with stomatal conductance (gs) in the commercial lines, a segregating F2 population of the B368 × Pima S-6 cross, and the collection of uncultivated G. barbadense. This relationship indicates that variation in gs is the main source of variation for Δ in both uncultivated and commercial G. barbadense. The positive correlation between Δ, gs and yield in the commercial Pima lines provides further evidence for selection pressures on higher gs ensuing from selection for higher yield and heat resistance. Selection for higher Δ could increase yield in crops grown in hot, high irradiance, and well-irrigated environments.

scholarly journals An observational constraint on stomatal function in forests: evaluating coupled carbon and water vapor exchange with carbon isotopes in the Community Land Model (CLM4.5)

2016 ◽  
Vol 13 (18) ◽  
pp. 5183-5204 ◽  
Author(s):  
Brett Raczka ◽  
Henrique F. Duarte ◽  
Charles D. Koven ◽  
Daniel Ricciuto ◽  
Peter E. Thornton ◽  
...  
Keyword(s):  
Stomatal Conductance ◽  
Carbon Isotope ◽  
Carbon Isotopes ◽  
Nitrogen Limitation ◽  
Carbon Isotope Discrimination ◽  
Stable Carbon Isotope ◽  
Atmospheric Co2 ◽  
Stable Carbon ◽  
Isotope Discrimination ◽  
Community Land Model

Abstract. Land surface models are useful tools to quantify contemporary and future climate impact on terrestrial carbon cycle processes, provided they can be appropriately constrained and tested with observations. Stable carbon isotopes of CO2 offer the potential to improve model representation of the coupled carbon and water cycles because they are strongly influenced by stomatal function. Recently, a representation of stable carbon isotope discrimination was incorporated into the Community Land Model component of the Community Earth System Model. Here, we tested the model's capability to simulate whole-forest isotope discrimination in a subalpine conifer forest at Niwot Ridge, Colorado, USA. We distinguished between isotopic behavior in response to a decrease of δ13C within atmospheric CO2 (Suess effect) vs. photosynthetic discrimination (Δcanopy), by creating a site-customized atmospheric CO2 and δ13C of CO2 time series. We implemented a seasonally varying Vcmax model calibration that best matched site observations of net CO2 carbon exchange, latent heat exchange, and biomass. The model accurately simulated observed δ13C of needle and stem tissue, but underestimated the δ13C of bulk soil carbon by 1–2 ‰. The model overestimated the multiyear (2006–2012) average Δcanopy relative to prior data-based estimates by 2–4 ‰. The amplitude of the average seasonal cycle of Δcanopy (i.e., higher in spring/fall as compared to summer) was correctly modeled but only when using a revised, fully coupled An − gs (net assimilation rate, stomatal conductance) version of the model in contrast to the partially coupled An − gs version used in the default model. The model attributed most of the seasonal variation in discrimination to An, whereas interannual variation in simulated Δcanopy during the summer months was driven by stomatal response to vapor pressure deficit (VPD). The model simulated a 10 % increase in both photosynthetic discrimination and water-use efficiency (WUE) since 1850 which is counter to established relationships between discrimination and WUE. The isotope observations used here to constrain CLM suggest (1) the model overestimated stomatal conductance and (2) the default CLM approach to representing nitrogen limitation (partially coupled model) was not capable of reproducing observed trends in discrimination. These findings demonstrate that isotope observations can provide important information related to stomatal function driven by environmental stress from VPD and nitrogen limitation. Future versions of CLM that incorporate carbon isotope discrimination are likely to benefit from explicit inclusion of mesophyll conductance.

Genetic variation in carbon isotope discrimination and its relationship to growth under field conditions in full-sib families of Piceamariana

1995 ◽  
Vol 25 (1) ◽  
pp. 39-47 ◽  
Author(s):  
Lawrence B. Flanagan ◽  
Kurt H. Johnsen
Keyword(s):  
Genetic Variation ◽  
Carbon Isotope ◽  
Carbon Isotope Discrimination ◽  
Isotope Composition ◽  
Stable Carbon Isotope ◽  
Leaf Tissue ◽  
Tree Height ◽  
Strong Negative Correlation ◽  
Isotope Discrimination ◽  
Sib Families

Measurements of the stable carbon isotope composition of leaf tissue were made on Piceamariana (Mill.) B.S.P trees from four full-sib families grown on three different field sites at the Petawawa National Forestry Institute, Ontario, Canada. The four families chosen exhibited genetic variation for growth characteristics. Genetic variation was also observed for carbon isotopic discrimination (Δ) among the families of P. mariana. In addition, a strong correlation occurred between Δ values measured on trees in 1991 and 1992, two years that had very different precipitation and temperature conditions during the growing season, indicating that the ranking of individual trees remained almost constant between years. A strong, negative correlation was observed between average carbon isotope discrimination and average tree height for the four families on the driest, least productive site, as was expected based on leaf photosynthetic characteristics. There was no significant correlation, however, between Δ values and growth on the other two study sites, where productivity was higher.

Relations of carbon isotope discrimination and other physiological traits to yield in common bean (Phaseolus vulgaris) under rainfed conditions

1994 ◽  
Vol 122 (2) ◽  
pp. 275-284 ◽  
Author(s):  
J. W. White ◽  
J. A. Castillo ◽  
J. R. Ehleringer ◽  
J. A. C. Garcia ◽  
S. P. Singh
Keyword(s):  
Phaseolus Vulgaris ◽  
Carbon Isotope ◽  
Water Deficit ◽  
Seed Yield ◽  
Combining Ability ◽  
Carbon Isotope Discrimination ◽  
Isotope Discrimination ◽  
Rainfed Conditions ◽  
Mechanisms Of Adaptation ◽  
Selection For

SUMMARYAlthough direct selection for seed yield under water deficit can result in genetic gains in the common bean (Phaseolus vulgaris L.), progress could be enhanced through selection for additional traits that are related to underlying mechanisms of adaptation to water deficit. Carbon isotope discrimination (Δ) has received considerable attention as an indicator of water use efficiency and adaptation to water deficit. To test the utility of Δ as a selection criterion, Δ and other traits were measured in F2 and F3 generations of a nine-parent diallel grown under rainfed conditions at two locations in Colombia with contrasting soil types. An irrigated trial was also conducted at one location. Significant (P 0·05) differences among parents, F2 and F3 were found for carbon isotope discrimination (Δ), leaf optical density (OD), leaf nitrogen (N) and potassium (K) concentrations, relative duration of pod-filling period (RDPF), shoot dry weight (SDW) and harvest index (HI). Effect of location and water regime and their interactions with genotype were also frequently significant. Heritability estimates, determined by regressing the F3 on the F2, ranged from 0·11±011 (S.E.) to 0·33 ±0·10 for OD, 0·22 ± 0·07 to 0·44±0·09 for N, 0·04±0·05 to 0·29±0·08 for K, 0·40 ± 0·08 to 0·43 ± 0·15 for RDPF and 0·30±0·22 to 1·00±0·24 for SDW. All values for Δ and HI did not differ significantly from zero. Correlations between seed yield and OD and RDPF were negative, whereas those with N, K, SDW, and HI were positive. For all traits, mean square values for general combining ability (GCA) were usuall significant and larger than those for specific combining ability (SCA). All significant GCA effects for Δ for ‘Rio Tibagi’, ‘San Cristobal 83’ and ‘Apetito’ were negative, while those for ‘Bayo Rio Grande’, ‘Bayo Criollo del Llano’, ‘Durango 222’ and BAT1224 were positive. Although Δappears unsuitable as an indirect criterion for selection for yield under water deficit, further study of genotypes exhibiting contrasting values of A might reveal differences in mechanisms of adaptation to water deficits, thus leading to other selection criteria or identification of valuable parental lines.

Stable carbon isotope discrimination in the smut fungusUstilago violacea

1986 ◽  
Vol 10 (2) ◽  
pp. 83-88 ◽  
Author(s):  
Oscar H. Will ◽  
Larry L. Tieszen ◽  
Mark Kellen ◽  
Tamara Gerlach
Keyword(s):  
Carbon Isotope ◽  
Carbon Isotope Discrimination ◽  
Stable Carbon Isotope ◽  
Stable Carbon ◽  
Isotope Discrimination

GAS EXCHANGE, GROWTH, YIELD AND BEVERAGE QUALITY OF COFFEA ARABICA CULTIVARS GRAFTED ON TO C. CANEPHORA AND C. CONGENSIS

2001 ◽  
Vol 37 (2) ◽  
pp. 241-252 ◽  
Author(s):  
J. I. FAHL ◽  
M. L. C. CARELLI ◽  
H. C. MENEZES ◽  
P. B. GALLO ◽  
P. C. O. TRIVELIN
Keyword(s):  
Stomatal Conductance ◽  
Gas Exchange ◽  
Carbon Isotope ◽  
Coffea Arabica ◽  
Carbon Isotope Discrimination ◽  
Growth Yield ◽  
Carbon Gain ◽  
Dry Period ◽  
Isotope Discrimination

Gas exchange, leaf carbon isotope discrimination, growth, yield and beverage quality were evaluated for two Coffea arabica cultivars (Catuai and Mundo Novo), grafted on to C. canephora and C. congensis progenies growing in open fields. During the years 1994 to 1997, grafting resulted in an average increase in bean yield of 151 and 89% for Catuai and Mundo Novo respectively. As analysed by sensory analyses and by the ratio between the mono-isomers and di-isomers of caffeoylquinic acid, beverage quality of the C. arabica was not altered by grafting. Shoot growth was significantly greater in grafted plants, showing an increase of 52% in total leaf area compared with the non-grafted plants. Under conditions of water excess in the soil there was little difference in the transpiration and stomatal conductance rates between the grafted and non-grafted plants, but the net photosynthesis was higher in grafted plants. With an accentuated water deficit in the soil in the dry period, the grafted plants showed significantly higher transpiration and stomatal conductance rates than the non-grafted plants, and similar values to those of C. canephora. Carbon isotope discrimination was greater in the grafted plants, suggesting greater root hydraulic conductance. The results suggest that the better performance of the grafted plants during the dry period was due to the greater capacity of the root system of C. canephora to provide water to the shoot thereby maintaining greater gas exchange in the leaves and consequently a greater carbon gain.

Genetic variation for leaf carbon isotope discrimination and its association with transpiration efficiency in canola (Brassica napus)

2020 ◽  
Vol 47 (4) ◽  
pp. 355
Author(s):  
Shek M. Hossain ◽  
Josette Masle ◽  
Andrew Easton ◽  
Malcolm N. Hunter ◽  
Ian D. Godwin ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Carbon Isotope ◽  
Carbon Isotope Discrimination ◽  
Genotypic Variation ◽  
Dry Weight ◽  
Transpiration Efficiency ◽  
Isotope Discrimination ◽  
Leaf Chlorophyll ◽  
Total Dry Weight ◽  
Positive Correlations

Drought is a major constraint to canola production around the world. There is potential for improving crop performance in dry environments by selecting for transpiration efficiency (TE). In this work we investigated TE by studying its genetic association with carbon isotope discrimination (Δ) and other traits, e.g. specific leaf weight (SLW) and leaf chlorophyll content (SPAD). Among the 106 canola genotypes – including open-pollinated, hybrid, inbred types and cytoplasmic variants – tested in the field and glasshouse there was significant genotypic variation for TE, Δ, plant total dry weight, SLW and SPAD. Strong negative correlations were observed between TE and Δ (–0.52 to –0.76). Negative correlations between Δ and SLW or SPAD (–0.43 to –0.78) and smaller but significant positive correlations between TE and SLW or SPAD (0.23 to 0.30) suggested that photosynthetic capacity was, in part, underpinning the variation in TE. A cytoplasmic contribution to genetic variation in TE or Δ in canola was also observed with Triazine tolerant types having low TE and high Δ. This study showed that Δ has great potential for selecting canola germplasm with improved TE.

Sign in / Sign up

Export Citation Format

Share Document