Foliar N application at anthesis alters grain protein composition and enhances baking quality in winter wheat only under a low N fertiliser regimen

Abstract

Wheat is the second biggest staple crop worldwide and is mainly consumed in the form of baked goods, requiring a specific flour quality. Grain protein concentration (GPC) is an underpinning parameter for baking quality and therefore strongly influences the value of wheat. It is a common strategy to increase GPC by combining high protein varieties with the application of a late dose of nitrogen. However, the late use of N fertilisers can cause environmental problems, such as nitrate leaching and gaseous losses. Furthermore, recent studies show, that there is only a weak relationship between GPC and bread volume. The aim of this study was to re-evaluate the merits of a late N application by investigating the effects of a late foliar N application, not only on GPC, but also on the gluten protein composition and on bread volume.In this study, an increasing GPC did not necessarily lead to improved baking quality. Baking performance rather depended on the grain protein composition. Only at a low N fertiliser level (100 kg N ha −1 ), the foliar N application decreased the HMW-GS/LMW-GS ratio and increased the gliadin/HMW-GS ratio, which led to an improved bread volume. These results imply that a late foliar N application can be used to effectively improve baking quality when the total N uptake was low due to low fertilisation or unfavourable weather conditions. The results also show that quality cannot be evaluated by measuring GPC alone but also needs information of storage protein composition as well as bread volume.

Comparative Study on Gluten Protein Composition of Ancient (Einkorn, Emmer and Spelt) and Modern Wheat Species (Durum and Common Wheat)

“…Thus, high protein content did not consequently lead to a better ratio of GLIA/GLUT and a high amount of glutenins. These findings are in accordance with the literature [21,22,23,24].…”

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

“…Similar to our results, other biostimulants obtained from marine, fungal, or protein hydrolysates have not been shown to change the protein content in wheat (Popko et al, 2018;Pichereaux et al, 2019). However, none of the treatments from our work resulted in a protein content below the level required by the industry (11.5%) even though this is not the best criterion to ensure baking quality (Rossmann et al, 2019).…”

“…Foliar application of Glutacetine R with N fertilizer at heading did not significantly affect the grain N concentration (Figure 2) but impacted the quantities of 11 proteins relative to the control (Figure 5). As suggested by Rossmann et al (2019), these changes in the grain proteome could have been due to the foliar application of N fertilizers at anthesis and might enhance baking quality. Indeed, the same authors showed that foliar N application increased HMW glutenin while decreasing LMW glutenin and α-/β-/γ-gliadins.…”

Effects of Genotype, Growing Season and Nitrogen Level on Gluten Protein Assembly of Durum Wheat Grown under Mediterranean Conditions

“…The composition and functionality of storage proteins have been significantly affected by growing season and genotype, while the effect of N fertilization level was rather small (Table S2) [50] as also resulted by PCA analysis. Several studies reported an increase in the proportions of the monomeric gliadins with increasing N availability [26,27].…”