Technological quality of wheat grains and flour as affected by nitrogen fertilization and weather condition

Abstract

The quality of grains and flour can be influenced by genetics, crop management, and environment. The objective of this study was to evaluate the technological quality of wheat grains and flour influenced by the interaction among genotype, nitrogen (N) fertilization and weather conditions in different regions of wheat crop adaptation in southern Brazil, aiming to support farmers and the bakery industry sector in their decision-making processes. The experiment was carried out in three environments (Londrina in rainfed and irrigated conditions; and Ponta Grossa in rainfed) in a randomized block design with a 10 × 2 factorial scheme. Ten wheat genotypes (BRS Sanhaço, BRS Graúna, BRS Gaivota, BRS Gralha-Azul, TBIO Sinuelo, TBIO Mestre, TBIO Sossego, TBIO Sintonia, TBIO Toruk, and Quartzo) and two N rates (40 and 120 kg ha-1) were assessed. The following technological quality analyses were performed in grains or flour: hectoliter weight, thousand-kernel weight, falling number, grain protein concentration, experimental flour extraction (i.e. flour yield), wet gluten concentration, and alveography. Increasing N rates from 40 to 120 kg ha-1 enhanced the concentrations of grain protein and wet gluten. However, it did not influence dough gluten strength and the commercial classification of the flour. Nitrogen fertilization also influenced the flour yield, dough tenacity and elasticity index, depending on the genotype × environment interaction. Environments with higher temperatures favored the flour yield and wet gluten concentration, while lower temperatures increased thousand-kernel weight and falling number. Water deficit increased the dough extensibility and grain protein concentration, whereas higher water availability favored the falling number, dough tenacity, and tenacity/extensibility ratio. Therefore, these outcomes are important drivers for farmers when choosing specific wheat genotypes for the environmental conditions of their farms, when they intend to meet the industrial requirements of mills and food companies that use wheat flour.