The effect of organic and conventional growing systems on quality and storage protein composition of winter wheat

Abstract

Protein composition of the grain storage proteins (evaluation using electrophoresis in polyacrylamide gel – the SDS-PAGE method) and selected parameters of bread-making quality in a set of 6 winter wheat varieties from organic and conventional growing in Central Bohemia (elevation 295 m a.s.l.) were evaluated during a two-year experiment (2004 and 2005). In comparison with the varieties from organic growing, wheat varieties from the conventional growing were characterized by twice the percentage of High Molecular Weight (HMW) glutenins, responsible for dough elasticity (conventional wheat in average 25.22%, organic wheat 12.71%). At the same time, varieties from conventional growing generally reached higher, more positive values of crude protein content and wet gluten content in grain dry matter, sedimentation index by Zeleny and yield of bread. On the other hand, wheat varieties from organic growing were mainly characterized by significantly higher percentage of nutritionally valuable albumins and globulins (organic wheat in average 17.69%, conventional wheat 7.33%). In both systems of growing the highest percentage of HMW glutenins was determined in varieties from the quality group E (elite, the most suitable for bread-making), while the varieties from the quality group C (wheat unsuitable for bread-making) reached the highest percentage of residual albumins and globulins.

Wheat Growing and Quality in Organic Farming

“…The proportion of crude protein in grain is reduced because of the reduced availability of soluble nitrogen (Krejčířová et al, 2006). The composition of storage proteins also changes, there are more protoplastic proteins (albumins and globulins) (Krejčířová et al, 2007), and this increases the nutritive value of grain.…”

The Influence of Farming Systems on the Technological Quality of Grain and Flour Cultivars of Winter Wheat

“…The difference between organic and conventional production system is the lack of mineral fertilizers and chemical pesticides in the former. Wheat grain from organic farming differs in its quality from that produced in conventional farms (Krejčířová et al 2007). Protein content and quality of gluten in wheat are the main differences in the resulting grain from different farming systems (Krejčířová et al 2006).…”

The effect of post-anthesis water supply on grain nitrogen concentration and grain nitrogen Šeld of winter wheat

“…Grain protein concentration and composition, tightly associated with nitrogen nutrition, are major parameters of flour quality properties (e.g. Krejčířová et al 2007) or barley grain quality (Váňová et al 2006, Pettersson andEckersten 2007). Modern highyielding wheat cultivars require corresponding input of nitrogen to guarantee a high yield and target grain quality parameters that enable farmers to attain financial bonus.…”