Economically Optimal Wheat Yield, Protein and Nitrogen Use Component Responses to Varying N Supply and Genotype

Abstract

Improvements in market value of hard red spring wheat (HRS, Triticum aestivum L.) are linked to breeding efforts to increase grain protein concentration (GPC). Numerous studies have been conducted on the identification, isolation of a chromosome region (Gpc-B1) of Wild emmer wheat (Triticum turgidum spp. dicoccoides) and its introgression into commercial hard wheat to GPC. Yet there has been limited research published on the comparative responsiveness of these altered lines and their parents to varied N supply. There is increased awareness that wheat genetic improvements must be assessed over a range of environmental and agronomic management conditions to assess stability. We report herein on economically optimal yield, protein and nitrogen use efficiency (NUE) component responses of two Pacific Northwestern USA cultivars, Tara and Scarlet compared to backcrossed derived near isolines with or without the Gpc-B1 allele. A field experiment with 5 N rates as whole plots and 8 genotypes as subplots was conducted over two years under semi-arid, dryland conditions. One goal was to evaluate the efficacy of the Gpc-B1 allele under a range of low to high N supply. Across all genotypes, grain yield responses to N supply followed the classic Mitscherlich response model, whereas GPC followed inverse quadratic or linear responses. The Gpc-B1 introgression had no major impact on grain protein, but grain N and total above ground crop N yields demonstrated quadratic responses to total N supply. Generally, higher maximum grain yields and steeper rise to the maxima (Mitscherlich c values) were obtained in the first site-year. Tara required less N supply to achieve GPC goals than Scarlet in both site-years. Genotypes with Gpc-B1 produced comparable or slightly lower Mitscherlich A values than unmodified genotypes, but displayed similar Mitscherlich c values. Target GPC goals were not achieved at economic optimal yields based on set wheat pricing. Economic optimization of N inputs

Simulation and Experimental Analyses of Nitrate Absorption for Indicator Utilization in Soilless Culture

“…6b). From an agronomical point of view, the relationship between the use of nitrogen fertilizers and plant production can be defined primarily as an increase in plant yield with increasing fertilizer supply [1,3]. The relationship between the supply of nitrogen fertilizer in previous study and the increase in production is seen in the low supply range starting from deficiency [2].…”

“…An increase in the supply of nitrogen from a range of deficiencies leads to an increase in yield [2]. To date, quantitatively summarized nitrogen use and yield response have been used as the basic decision-making process for the use of appropriate fertilizers [3]. Recently, under open field conditions, various sensing techniques have become available to use during the decisionmaking process regarding nitrogen use.…”

“…The drainage volume was measured by reading the water level in the daily drainage tank after the end of irrigation. For NO3 analysis, ion chromatography was performed (730 Professional IC, Metrohm, Switzerland). In the experiment, tomatoes were planted on October 8, 2019, and DNAI EC and DNAI NO3 measurements were performed from December 31, 2019 (84 days after transplanting, 84 DAT) to January 28, 2020 (112 DAT) after planting.…”

Nitrogen losses from hard red spring wheat fields in the northern plains

“…Crop production is the single largest cause of the increasing reactive N in the biospheric cycle (Smil, 1999). Aiming at protein‐based profitability with increased N supply has potential to negatively impact the environment; application of fertilizer N required to produce >400 kg protein ha −1 also left >130 kg residual N ha −1 (Pan et al., 2020). Optimizing NUE through fertilizer‐N management can reduce N losses, like N 2 O and NH 3 losses, and the cost of fertilizer application (Snyder et al., 2009).…”

Biostimulant Effects of Glutacetine® and Its Derived Formulations Mixed With N Fertilizer on Post-heading N Uptake and Remobilization, Seed Yield, and Grain Quality in Winter Wheat

“…Due to economic and ecological factors, there is a trend in Europe to limit chemical inputs for wheat, especially N (Boisson et al, 2005), despite it being essential for both maximal yield and optimal quality in terms of protein content. Seed yield and grain protein concentration are two major challenges in winter wheat, as these traits are dominant determinants of the economic value of the harvested product (Pan et al, 2020). Protein content influences price, especially due to its impact on the rheological qualities of flour (Nadaud et al, 2015).…”