抄録
長野県農事試験場が育成した精麦用六条オオムギ品種のミノリムギ,シュンライ,ファイバースノウ,シルキースノウについて5年間の千粒重,硝子率,粒厚分布,55%搗精時間,55%精麦白度,砕粒率,完全搗精粒率,黒条線支配率,30%搗精粉ペースト色相を調査した.形質間相関係数を算出した結果,精麦白度との間に2.6mm以上の粒厚分布で正の,黒条線および硝子率で負の有意な相関がそれぞれ認められた.重回帰分析の結果,これら3形質で精麦白度の変異の約80%を説明できた.精麦白度へのそれぞれの寄与の大きさは,粒厚分布>黒条線支配率>硝子率の順であり,またこれら形質の遺伝率は,0.56〜0.71と中位の値を示した.しかし,精麦白度そのものに有意な品種間差は認められず,遺伝率(0.26)も低かった.このため今後現在の普及品種より更に精麦白度が高い品種の育成には,精麦白度のみならず,粒厚分布,黒条線支配率および硝子率を同時に選抜することで精麦白度の選抜効果を補う必要があると考えられた.
Characters related to the pearling quality of four six-row barley varieties Shunrai, Fibersnow, Silkysnow and Minorimugi, which were developed for pearling use at Nagano Prefecture Agricultural Experiment Station, were investigated during the period from 2002 to 2006. 1000-grain weight, steely-grain rate, grain-thickness distribution, furrow-width rate of 55% pearled grains, pearling time, 55% pearled grain whiteness, perfect-pearl-grain rate after 55% pearling, ratio of broken kernels after 55% pearling and 30% pearled grain flour paste color were analyzed. Steely-grain rate, grain-thickness distribution and furrow width were highly correlated to the pearled grain whiteness. The higher distribution of 2.6 mm or thicker grains, the lower furrow width of pearled grains and the lower steely-grain rate, respectively, were related to the higher pearled grain whiteness. Multiple regression analysis indicated that these three factors controlled about 80% of pearled grain whiteness. The grain thickness contributed most to the whiteness. Furrow width affected whiteness more than the steely-grain rate. The varietal differences in these three traits were considered to be significant. The values of the heritability estimates of grain-thickness distribution, furrow width of pearled grains and steely-grain rate were 0.71, 0.62 and 0.56, respectively. However, varietal differences in pearled grain whiteness were statistically not significant and the value of the heritability estimate was 0.26. Therefore, screening only based on pearled grain whiteness was not effective to select whiter pearled grains. More emphasis should be placed on the selection of grain thickness, furrow width of pearled grains and steely-grain rate, and each factor should be modified independently to develop barley varieties with whiter pearled grains.
