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Arabinoxylans are hydrophilic nonstarch polysaccharides found in wheat grain as minor constituents. Arabinoxylans can associate with large amounts of water through hydrogen bonding and can form oxidative gels. These properties are important factors in end‐use quality of wheat. The objective of this study was to delineate the influence of wheat cultivar and growing environment on variation in water‐soluble (WS‐AX), waterinsoluble (WI‐AX), and total (TO‐AX) arabinoxylan contents of flour and whole grain meal. This study included seven spring and 20 winter soft white wheat cultivars grown in 10 and 12 environments, respectively (each evenly split over two crop years). Univariate analysis of variance (ANOVA) and multivariate analysis of variance with canonical analysis (MANOVA) was used to evaluate sources of variation. Variation in arabinoxylan contents and absolute amounts (xylose equivalents) among the two cultivar sample sets (spring and winter) was similar, and both cultivar and environment were significant sources of variation. The cultivar‐by‐environment interaction was relatively unimportant. Results indicate that the variation in arabinoxylan content is primarily influenced by cultivar and secondarily influenced by environment. Within arabinoxylan fractions, WS‐AX content is primarily influenced by genotype, while WI‐AX content is more greatly influenced by the environment. 相似文献
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Laryngotracheitis was diagnosed in a flock of molted, caged table-egg-layers. Morbidity was restricted to an area of the house in which the birds had been exposed to smoke from a fire in the house and to a powdered chemical fire-extinguisher used on the fire. Mortality in this group began to rise 6 days after the fire and continued to be above normal for about 3 weeks. Feed consumption dropped for about 1 1/2 weeks after the fire but was normal or above normal during the rest of the disease outbreak. Egg production dropped slightly for 1 week after the fire, then returned to normal. Microscopic tracheitis in the exposed birds continued for 11 weeks after the fire. Hens outside of the smoke-affected area did not show histopathological changes or shed laryngotracheitis virus. 相似文献
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