Abstract
The varietal difference of the yield components and pearling quality in four varieties used as pearled barley in the Hokuriku region were analyzed for five years, to breed new varieties that stably exhibit superior traits. There were no significant genotype × year interactions in the number of panicles, 1000-grain weight, plump-grain rate, crude protein content, steely-grain rate and rigidity value. Significant interactions were detected in plump-grain yield, 1-liter-grain weight, pearl whiteness, and pearling time. ‘Minorimugi’ had high plump-grain yield in the years suitable for barley growth, but markedly low plump-grain yield in the years with much snow or rain at the ripening stage. ‘Hokuriku kawa 35’ was the most stable variety in yield. Varieties with the heaviest or lightest 1-liter-grain weight varied with the year. ‘Shunrai’ was the most stable variety in pearling quality. The pearl whiteness was the lowest and pearling time was the longest in ‘Minorimugi’ every year. We suggest that the annual variations of plump-grain yield, 1-liter-grain weight, and pearling quality were mainly caused by precipitation during the ripening stage, and that the effects of environmental factors varied with the variety. It is necessary to examine these traits for several years including the years with undesirable conditions to breed fine varieties stably. The rate of infection with scald varied with the year, but even susceptible varieties did not show the symptom every year under ordinary cultivation conditions.
