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Nitrogen fertilization effects on nitrogen uptake, translocation and protein composition of hard red winter wheat in relation to end use quality
Abstract
Soil nitrogen availability has a large influence on wheat grain protein concentrations. However, influence of soil nitrogen on protein deposition and protein quality may vary among wheat genotypes. A study was conducted to evaluate soil N response of hard red winter wheat genotypes in terms of: (1) Concentrations of N in tillers and grain during grain fill, and (2) Changes in protein quality during grain fill. Fifteen wheat genotypes were grown at Mead, Nebraska in 1989 and 1990 under four fertilizer treatments: 0, 45, and 90 kg/ha N; 39 kg/ha N with 45 kg/ha sulphur. Plant samples were obtained weekly during the grain fill period. Tillers were dried, and evaluated for N concentration. Heads were removed, freeze dried, and grains extracted for estimation of N concentration and protein quality. Protein quality was measured based on solubility in salt water, ethanol, KOH, and SDS solutions. Flour from harvested grain was used for mixograph analyses. Increasing soil N increased N concentrations in tillers and grain, and improved mixing properties. However, grain protein quality, as measured by protein solubility characteristics, was not altered with increasing soil N. Addition of sulphur to the soil had no influence on tiller or grain N levels, protein quality, or mixing properties. Wheat genotypes differed for tiller and grain N concentrations, protein solubility characteristics, and mixing quality. However, all genotypes responded similarly to soil N treatments; genotype by treatment interactions were non-significant for tiller and grain N and most measures of protein quality. Among the genotypes, tiller and grain N concentrations were shown to be unrelated. Salt water, ethanol, and KOH soluble proteins were deposited in an asynchronous manner during grain fill. As grain fill progressed, salt water soluble proteins decreased, whereas alcohol and KOH soluble proteins increased as a proportion of total protein. Soil N treatments did not alter the relative proportions of proteins at any stage of grain fill. Significant differences in protein deposition were observed among genotypes. Temperature stress occurring during grain fill in 1990 affected protein deposition and quality lowered.
Subject Area
Agronomy|Plant propagation
Recommended Citation
Niaz, Shahid, "Nitrogen fertilization effects on nitrogen uptake, translocation and protein composition of hard red winter wheat in relation to end use quality" (1993). ETD collection for University of Nebraska-Lincoln. AAI9402400.
https://digitalcommons.unl.edu/dissertations/AAI9402400