Changes in technological quality of food wheat in a four crop rotation

The evaluation of technological characteristics of food wheat (Triticum aestivum L.), grown in a four crop rotation (corn, barley, pea, wheat) since 1994, is presented. Samples of grain, whole grain meals, and flours of the varieties Vlada and Samanta were analyzed. The samples originated from field trials at a research base nearNitra. All important methods of the assessment of the raw material technological quality (intended use for milling and baking) were applied. A total of 22 characteristics were evaluated (15 of them are shown in Table 1). The highest abundance of highly significant (significance levels being results of both parametric and nonparametric methods) changes (a £ 0.01) in quantity (grain and flour yield) and quality (gluten and its properties, water-binding capacity of flour, a-amylase activity) was observed between different years (7). The soil management methods (3; 2 + 1) had a significant (a £ 0.05) influence on the test weight (grain volume mass) and gluten content. In interaction with the year (as a factor), they significantly influenced gluten swelling number (Q-number) and highly significantly the activity of a-amylases. Highly significant differences were also found between varieties (2; 1/1), significant ones in interaction with soil management. Fertilization (3) and other interactions of factors were not statistically significant. Parameter means for factor levels (along with statistical significance of the influence of particular factors) and simple quality coefficients (used for the ranking of factor levels) are shown in Table 1.