This dissertation describes the development of new genetic resources of spring barley in a process called prebreeding. Suitable genotypes were detected by using appropriate methods of selection (greenhouse tests, molecular markers, filed tests in provocative conditions). They could be used directly in the next breeding programmes for increased resistance to pathogen Pyrenophora teres f. teres causing net form of net blotch or for improved grain quality usable in the food industry and in nutrition of farm animals.

The content of beta-glucans and arabinoxylans in barley grain, malt and wort was monitored. The varieties of barley were Pionier, Libuše, Manta, Tango, KWS Amadora, Kampa, KWS Irina, Francin, Odyssey, Overture, Vendela, Petrus, Laudis 550, Sunshine, Kangoo, Xanadu, Sebastian, Bojos and Malz. These varieties were grown on three different habitats (Uherský Ostroh, Věrovany and Vysoká u Příbramě). The content of beta-glucans and arabinoxylans was also analysed in five different types of beer. In brewing and malting industry the content of beta-glucans and arabinoxylans is mainly monitored because of their negative influence on decanting of wort and filtration of beer. These substances can contribute to turbidity and precipitation in beer and thus negatively effect the stability of beer. The content of beta-glucans in barley grain, malt, wort and beer was determined by FIA method and the content of arabinoxylans was determined in barley grain, wort and beer by Douglas method. The highest content of beta-glucans in barley grain was found in 14/19 varieties at Uherský Ostroh, where the amount of beta-glucan content was in the range of 3,65-5,60 %. The highest beta-glucan content in malt was found in 17/19 varieties at Vysoká u Příbramě, where the beta-glucan content was between 0,15-0,79 % and the highest content of beta-glucans in wort was found in 16/19 varieties also at Vysoká u Příbramě. There was the beta-content in the range of 22-184 mg/l. The results of content of arabinoxylans in barley grain and wort were more balanced. The highest content of arabinoxylans in barley grain was found in 10/19 varieties at Věrovany. The content of arabinoxylans at this habitat was in the range of 3,04-4,56 %. The highest content of arabinoxylans in wort was determined in 8/19 varieties at Uherský Ostroh. The content of arabinoxylans at this habitat was in the range of 542-1040 mg/l. The highest content of beta-glucans in samples of beer was determined in a sample of light lager (207 mg/l) and the highest content of arabinoxylans was found in a samle of wheat lager (1465 mg/l).