The variability and interdependence of basic technological quality parameters of maize hybrids in long-term research

In the process of hybrid maize breeding, the greatest attention is directed towards increasing the level and stability of the yield, while grain quality is of secondary importance. The very principles of hybrid breeding, as well as the economic aspects and competition between different breeding companies, have led to an enormous narrowing of the genetic basis of commercial maize hybrids. Concurrently, there is usually a small number of often related hybrids of similar technological and nutritional quality present on the market. Six best-selling ZP maize hybrids in the previous ten years were chosen as the subject of this study. In the period from 2009-2018, both the yield components and parameters of technological and nutritional quality of the grain were studied. It was found that the examined parameters varied a lot in different years of production and that some parameters were more influenced by genotype (number of kernel rows per ear, portion of pericarp, and crude fiber content) while others were more influenced by the environment (kernel weight per ear, total protein, starch, and oil content, respectively). The amount and the distribution of precipitation during the vegetative period affected not only the yield components i .e. grain yield but also the technological quality parameters and nutritional properties of the grain. Based on the observed parental components, it is evident that they are related hybrids that, despite the high genotype by environment interactions, consequently have similar parameters of technological quality and nutritional composition. The imperative is to develop special breeding programs aiming to create both the starting material and parental components to provide hybrids of improved technological quality and nutritional properties on the market. In that way, the needs of the processing industry for raw materials of certain characteristics can be met.