RESULTS OF VARIETAL TRIALS CONDUCTED WITH SPRING BARLEY IN SUGAR-BEETGROWING REGION

In the years 1990 to 1992 the effect of varieties and new breed of spr ing barley on the grain yield quantity and quality and on some botanic al plant properties was studied in field trials on medium-texture Cher nozem in sugar beet growing region at Ivanovice na Hane. The trials af ter sugar beet comprised 24 varieties and new breed and with respect t o the quality of a forecrop, nitrogen was not applied at all. The most significant change in new breed and new varieties of spring barley co mpared with older varieties is reduction in plant length. The lowest g rain yield and quality were determined in the oldest tested varieties Valticky and Diamant, the highest yield and the lowest crude protein i n grain was on average for three years found in the Orbit variety. In die trials, despite the statistical significance of differences in gra in yields, no significant trend of an increase in the grain yield appe ared in the latest varieties and new breeds. The grain yield quantity is evidently limited by ecological conditions and in particular, by a lack of water in soil. Besides the Diamant variety, which had the diff erence in the proportion of above 2.5 mm sieve lower than 70 %, anothe r varieties and new breeds reached basic or marketable quality.