Effects of preceding crop, year, growing intensity and variety on grain yield and quality parameters in spring barley

Changes in the structure of grown crops to the detriment of root crops resulted in such a state that it is necessary to revise past cropping practices of spring barley for malting purposes and to assess proportions of the effect of current preceding crops, year, growing intensity and varieties on grain yield and quality parameters of this crop. The paper presents results from the period of 2005-2008. Spring barley (five varieties) was grown after four preceding crops (sugar beet, maize, cereal crop and oilseed rape). All varieties, after all preceding crops, were grown using three crop management practices. In the experiments, grain yield, volume weight, percentage of plump kernels (2.5-mm sieves) and N-substances content were evaluated. The effect of the year predominated in the experiments. It was due to a high instability of crop rotations containing only a few crops often repeated in the rotation and leaving a large amount of organic matter in the soil. It is followed by another important factor, weather conditions. If there was a lack of moisture during a short growing season of spring barley, especially at early growth and developmental stages, an overall structure of the stand was less able to form the required yield with high volume weight, low content of N-substances and a high percentage of plump kernels. The soil environment determined by the preceding crop limited or, conversely, stressed the negative effect of the weather in the given year. The highest grain yield as well as the highest volume weight were produced after preceding crop sugar beet. The percentage of plump kernels (87.8%) was also high after sugar beet. Content of N-substances was on average of all years and variants 12.1%.