Produção de trigo na região sul do Rio Grande do Sul: influência de práticas de manejo sobre a qualidade dos grãos e farinhas

Abstract

Wheat is one of the most cultivated cereals globally, being essential in human and animal nutrition. The quality of its grains is influenced by factors such as genetics, environment and crop management. The search for adapted genotypes and effective management practices is essential to improve wheat quality and productivity. This study aimed to evaluate the effects of wheat production in the southern region of Rio Grande do Sul, considering variations in harvest time and fungicide application, on the physical and chemical quality of wheat grains and flour from different genotypes. The experiments were conducted in the 2019 and 2020 crop seasons at the Centro Agropecuário da Palma, Capão do Leão/RS. In the first chapter of this research, ten wheat genotypes recommended for cultivation in the southern region of Brazil were used: BRS Belajoia, BRS Pastoreio, BRS Reponte, ORS 1403, TBIO Audaz, TBIO Ponteiro, TBIO Sinuelo, TBIO Sonic, TBIO Sossego, and TBIO Toruk. These genotypes were selected for the study with the objective of evaluating the quality of the grains in response to two harvest times. The results indicated notable variations in grain quality between different wheat genotypes and harvest times, highlighting the influence of the interaction between these factors in differentiating the analyzed materials. The cooking properties of the grains showed significant variations between genotypes, emphasizing the need to carefully select genotypes for this purpose. Most genotypes exhibited higher test weight and thousand kernel weight values in the first harvest. Furthermore, the prolonged stay of the grains in the field harmed their quality in terms of health, as Fusarium-damaged grains increased in the second harvest. In general, the falling number decreased in the second harvest. Regarding the viscosity behavior of flours, a greater influence of the harvest time was observed in specific genotypes (TBIO Ponteiro, TBIO Sinuelo and TBIO Sossego). The second chapter covered the effects of fungicide management and the use of two doses on the performance of four wheat genotypes (TBIO Audaz, TBIO Capricho CL, TBIO Ponteiro, and TBIO Toruk). Fungicide application provided significant benefits to wheat yield measurements. There was a notable increase in yield, test weight and thousand kernel weight compared to the control treatment. The shriveled and Fusarium-damaged grains reduced with the use of the pesticide and in addition, the amount of the mycotoxin deoxynivalenol decreased considerably for all genotypes after its application. Our results provide new information about wheat production in Brazil, providing new insights for its application in the southern region of Rio Grande do Sul, emphasizing the complexity and variety of factors that influence the final quality of the grains.