Carbon isotope discrimination of two-rowed and six-rowed barley genotypes under irrigated and non-irrigated field conditions

Abstract

2006. Carbon isotope discrimination of two-rowed and six-rowed barley genotypes under irrigated and non-irrigated field conditions. Can. J. Plant Sci. 86: 433-441. Carbon isotope discrimination (∆) has been widely used to estimate the water-use efficiency (WUE) of C 3 cereals including barley (Hordeum vulgare L.). Genetic lines of barley belong to two phenotypic classes for ear morphology, either two-rowed or six-rowed, a simply inherited trait. We tested the value of ∆ as a predictor of grain yield and WUE for these two types of barley under different conditions of water availability. We also investigated if differences in plant morphology and yield parameters between these two types resulted in different carbon dynamics and different ∆ values for grain, awn and flag leaf. We conducted field experiments for 3 consecutive years with genetic lines of both ear types in northern Utah and southeastern Idaho under irrigated and non-irrigated conditions, including two line-source sprinkler experiments. Correlations between grain yield and ∆ values of flag leaf, awn and grain were stronger in combined analyses across ear types than in analyses within two-rowed (2R) and six-rowed (6R) types. Nevertheless, we found that ∆ of mature awns and grains were a good predictor of yield for both barley types under low to moderate water stress. However, ∆ was not a reliable predictor for barley yield under severe water stress. Pearson's correlations were used to test associations between ∆ values and several yield parameters (heading date, above-ground dry matter, harvest index, grain mass per fertile tiller). Our data indicated that among the field-grown genetic lines tested, the two types of barley differed in ∆ values for grain, awn and flag leaf. Values of ∆ for 2R barley were usually lower, suggesting higher WUE, than those for 6R types. Fundamental differences in sink size or grain mass per fertile tiller between 2R and 6R cultivars probably have important consequences on carbon/water metabolism at the whole tiller level. Jiang, Q., Roche, D. et Hole, D. J. 2006. Discrimination des isotopes de carbone chez les génotypes d'orge à deux et à six rangs cultivés avec et sans irrigation. Can. J. Plant Sci. 86: 433-441. On recourt souvent à la discrimination des isotopes de car-bone (∆) pour estimer l'efficience de l'utilisation de l'eau (EUE) des céréales C 3 telle l'orge (Hordeum vulgare L.). Les lignées génétiques d'orge se divisent en deux groupes phénotypiques reposant sur la morphologie de l'épi (deux rangs ou six rangs), car-actère transmis simplement. Les auteurs ont tenté d'établir si la valeur de ∆ pourrait servir à prévoir le rendement grainier et l'EUE des deux types d'orge dans des situations variables, en l'occurrence selon la quantité d'eau disponible. Ils ont aussi déterminé si certaines variations dans la morphologie de la plante ou si les paramètres du rendement des deux types d'orge pourraient donner lieu à une dynamique différente du carbone et à des valeurs distinctes de ∆ pour le grain, les barbes et la feuill...

Evaluation of Grain Yield and Three Physiological Traits in 30 Spring Wheat Genotypes across Three Irrigation Regimes

“…Merah et al (1999) reported that the flag leaf CID at anthesis correlated with grain yield only under strong water limitation conditions in durum wheat. Jiang et al (2006) Table 4. Pearsons' correlation coefficients between grain yield (GY, g m-2) and other evaluated traits (days to heading [DTH, height [HT], flag leaf senescence [FLS,[0][1][2][3][4][5][6][7][8][9][10], carbon isotope discrimination [CID, %o], and canopy temperature [CT, °C] ta, c, and d stand for traits assessed at Feekes 10,5,2 (anthesis), Feekes 11,1 (kernels miiky ripe), and Feekes 11,2 (kerneis mealy ripe) (Miller, 1999), respectively, *NS, nonsignificant at the 0,05 probability ievei, SNA, not avaiiabie, indicated that CID was not a reliable predictor for barley yield under severe water stress.…”

“…Merah et al (1999) reported that the fl ag leaf CID at anthesis correlated with grain yield only under strong water limitation conditions in durum wheat. Jiang et al (2006) Figure 7. Comparison of the mean canopy temperature evaluated at Feekes 11.2 (kernels mealy ripe) (Miller, 1999) indicated that CID was not a reliable predictor for barley yield under severe water stress.…”

“…Carbon isotope discrimination has been used as a physiological tool to evaluate a large number of genotypes for grain yield and water use effi ciency under fi eld conditions Tokatlidis et al, 2004;Monneveux et al, 2005). Association between CID and grain yield under drought was also reported in several cereal crops, including wheat (Sayre et al, 1995;Merah et al, 1999Merah et al, , 2001 and barley (Hordeum vulgare L.) (Jiang et al, 2006). However, the reported correlations vary depending on the analyzed organ or tissue, the stage of sampling, and the growth environment (Merah et al, 1999;Jiang et al, 2006;Xu et al, 2007).…”

Agricultural innovation and resilience in a long-lived early farming community: the 1,500-year sequence at Neolithic to early Chalcolithic Çatalhöyük, central Anatolia

“…Riehl 2009). Modern two-row barley has higher water use efficiency than six-row barley, meaning that it is better yielding in droughted environments, while six-row barley is better yielding in well-watered conditions (Voltas et al 1999;Jiang et al 2006;Aniya et al 2007). The inherent reproductive superiority of six-row barley means that shifts towards two-row barley, as documented at Çatalhöyük, require strong selection for two-row barley, either through cultural practices or ecological conditions (Palmer et al 2009).…”