Can carbon isotope discrimination and ash content predict grain yield and water use efficiency in wheat?

Drought is the main factor affecting crop grain yield. Increasing grain yield under drought and crop water use efficiency (WUE) is essential for enhancing world crop production and food availability. The objective of this study, carried out in India on 20 durum wheat cultivars, under three water regimes (full irrigation, limited irrigation and residual soil moisture) and during two seasons, was to investigate the potential use of plant traits (particularly carbon isotope discrimination, [Delta], and ash content, ma) to predict grain yield and WUE in wheat. WUE components were estimated using a soil water balance model (Budget) allowing comparison of environments in data scarce situations. A highly significant correlation was noted between grain yield and grain [Delta] across water regimes. However, the associations between grain yield, [Delta] and ma were found to depend highly on the water regime and environmental conditions. The association between grain yield and grain [Delta] was significant under full irrigation in season 1 and under residual soil moisture in season 2. Significant positive correlations were noted in both seasons between grain yield and leaf [Delta] under residual soil moisture and between grain yield and leaf ash content at anthesis under limited irrigation. A significant correlation was found across environments between grain and leaf [Delta] and T, the quantity of water transpired during the growth cycle, as estimated by the soil water balance model. T also significantly correlated to grain and leaf ma. Variation in WUE across environments was driven more by runoff, drainage and soil evaporation than by harvest index and transpiration. The associations between WUE and transpiration, runoff and [Delta] were negative but not significant. WUE was significantly correlated with leaf and grain ma at maturity. The study indicates that [Delta] and ma can be used as indirect selection criteria for grain yield and suggests that ma is a good predictor of transpiration, grain yield and WUE across environments. The use of mechanistic models that allows differentiating between cultivars should permit in a next future to analyze the relationships between WUE, [Delta] and ma across cultivars and evaluate the possibility to use these traits as predictors of WUE in wheat breeding programs.Ash content Carbon isotope discrimination Soil water balance model Transpiration Water use efficiency

Thermoresponsive copolymers with pendant d-galactosyl 1,2,3-triazole groups: Synthesis, characterization and thermal behavior

A galactose containing glycomonomer has been synthesized by copper catalyzed azide\u2013alkyne cycloaddition reaction (CuAAC) of 6-azido-6-deoxy-1,2:3,4-di-O-isopropylidene-a-D-galactopyranose with propargyl acrylate. This monomer was subjected to homopolymerization and copolymerization with N-isopropylacrylamide (NIPAm) at different compositions by free radical polymerization using 2,20-azobisisobutyronitrile (AIBN) as an initiator. The composition of the copolymer was determined by 1H-NMR spectroscopy. Upon acid hydrolysis of acetonide protected polymers, water-soluble deprotected polymers were obtained. The polymers were characterized and confirmed by NMR, IR, GPC and thermal analytical techniques. The protected and deprotected copolymers showed a sharp cloud-point temperature and a linear correlation was obtained between the lower critical solution temperatures (LCST) and the concentration of glycomonomer in the copolymers. This allows tuning the thermal response by simply altering the copolymer composition. Water contact angle experiments showed the changes in the hydrophilicity of copolymers with compositions that supported the LCST results. The glass transition temperature of protected copolymers followed a regular monotonic decreasing trend with increasing glycomonomer content, whereas Tg of deprotected copolymers increased due to H-bond interaction. The attempts to develop thermoresponsive polymers having LCSTs at physiological temperature were successfu

Glycopolymer Grafted Polystyrene Nanospheres

The synthesis and characterization of spherical sugar containing polymer brushes consisting of PS cores onto which chains of sugar containing polymers have been grafted via two different techniques are described. Photopolymerization in aqueous dispersion using the functional monomer MAGlc and crosslinked or non crosslinked PS particles covered with a thin layer of photo initiator yielded homogeneous glycopolymer brushes attached to spherical PS cores. As an alternative, ATRP was used to graft poly N acetylglucosamine arms from crosslinked PS cores. Deprotection of the grafted brushes led to water soluble particles that act as carriers for catalytically active gold nanoparticles. These glycopolymer chains show a high affinity to adsorb WGA whereas no binding to BSA or PNA could be detecte

Superhydrophobic PU Sponge Modified by Hydrophobic Silica NPs-Polystyrene Nanocomposite for Oil-Water Separation

In this study, the hydrophobic silica nanoparticles (NPs) are synthesized by simple sol–gel processing of polymethylhydrosiloxane (PMHS). The nanocomposite solution is prepared by adding hydrophobic silica NPs in polystyrene solution and applied on the skeleton of polyurethane sponge by simple immersion-drying process. The as-prepared sponges exhibited superhydrophobic property with water contact angle 161° and oil contact angle nearly 0° and can separate oil from oil–water and oil–muddy water mixture. The superhydrophobic sponge has sustainable anti-wetting property under cross sectional cutting, pressing and twisting, and different pH environment. Such superhydrophobic sponge is suitable for practical application on a large scale.This work is financially supported by DST ? INSPIRE Faculty Scheme, Department of Science and Technology (DST), Govt. of India. [DST/INSPIRE/04/2015/000281]. SSL acknowledges financial assistance from the Henan University, Kaifeng, P. R. China. The authors greatly appreciate the support of the National Natural Science Foundation of China (21950410531).Scopu