Germination of malting barley grains when using recycled steep-out water

The objective of the study was to quantify the inhibitory effect of repeated use of steep-out water on selected germination parameters. Ten malting barley genotypes from three sites were tested in this research. Statistically significant inhibitory effects of recycled steep-out water on germination rate GR (reduction by 22.8% on average compared to distilled water), germination index GI (reduction by 10.9% on average compared to distilled water), as well as germination energy GE (reduction by 2.4% on average compared to distilled water) were recorded. Compared to the average GI of all varieties in distilled water (4.6), GI was lower by 6.7% and 6.1% for Laudis 550, 5.0% and 6.3% for Manta, but 14.1% and 13.3% for Tango, and 17.2% and 15.2% for Vendela when water from the first and second steeps was used. The varietal differences identified, as well as the effect of provenience, indicated different levels of GI reduction depending on the vigour of the caryopsis. Caryopses of the genotypes with higher vigour are able to cope better with the inhibitory effect of the steep-out water on germination.