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BACKGROUND The structure of β-glucan influences its use in cereal-based foods and feed. The objective of this study was to determine the effect of environment (E) and genotype (G) on β-glucan fine structure and its genetic control in two-row spring barley with normal starch characteristics. RESULTS A population of 89 recombinant inbred lines, derived from the cross of two-row spring barley genotypes Merit × H93174006 ( H92076F1 × TR238), was characterized for concentration and structure of grain β-glucan in two environments. Results showed that concentrations of β-glucan, DP3, DP4 and DP3 + DP4 were positively correlated with each other, suggesting no preference for DP3 or DP4 subunit production in high- or low-β-glucan lines. The concentrations of β-glucan, DP3, DP4 and DP3: DP4 ratios were significantly influenced by genotype and environment. However, only DP3: DP4 ratio showed a significant effect of G × E interaction. Association mapping of candidate markers in 119 barley genotypes showed that marker CSLF6_4105 was associated with β-glucan concentration, whereas Bmac504 and Bmac211 were associated with DP3: DP4 ratio. Bmac273e was associated with both β-glucan concentration and DP3: DP4 ratio. CONCLUSION The grain β-glucan concentration and DP3: DP4 ratio are strongly affected by genotype and environment. Single-marker analyses suggested that the genetic control of β-glucan concentration and DP3: DP4 ratio was linked to separate chromosomal regions on barley genome. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Miscanthus, switchgrass, and softwood chip biochars, produced by slow pyrolysis, were characterized to evaluate their properties in light of potential alternative and novel applications. This work investigated specific physical and chemical properties of biochars that have not been previously reported. Atomic force microscopy (AFM), moisture absorption, and electrical and thermal analysis were conducted to demonstrate the mechanical, physical, and chemical properties of biochars. In addition, elemental analysis, specific surface area, Fourier transform infrared in the attenuated total reflectance (FTIR-ATR), and X-ray diffraction were performed. The state-of-art quantitative nano-mechanical measurement yielded a modulus of elasticity of approximately 10 GPa for the wood chip biochar, while the grass-based samples exhibited a comparatively lower modulus of approximately 5 GPa. In addition, the pore blocking phenomenon by water molecules was identified as a cause for atypical behavior of the biochars' moisture absorptions, resulting in wood chip biochar having the lowest equilibrium moisture content of 6.2 wt.%. Results from electrical and thermal conductivity measurements demonstrated relatively lower values in comparison to carbonized biomass. [ABSTRACT FROM AUTHOR]

A protocol was developed to monitor persistence and spread of a genetically modified strain of the growth promoting diazotroph Azorhizobium caulinodans used to inoculate field grown wheat. The protocol was used to identify an endogluconase (egl) overproducing strain of A. caulinodans isolated from inoculated soils. A detection limit of 2500 cfu g-1 and 108 -1010 cfu g-1 of soil was determined using the BIOLOG® fingerprinting method and PCR technique, respectively. Since none of the tested samples were positive for the bacteria or the Egl 1 gene construct, it was concluded that A. caulinodans ORS 571 pGV910-C1 did not persist or spread in any of the tested field locations. This result may be due to low soil temperatures and competition of indigenous microorganisms: environmental factors that were not favorable for the diazotroph to thrive in the test locations. The application of different inoculation methodologies, as well as the study of other rhizobial genera for the inoculation of wheat in further experiments, is strongly recommended. [ABSTRACT FROM AUTHOR]