Inheritance of grain fill rate in barley

Grain fill rate is an important characteristic influencing productivity of barley (Hordeum vulgare L.) in northern areas of production. This study was conducted to determine the inheritance of grain fill rate and its relation ship to other agronomic traits. Thirty-three doubled haploid lines and pare nts from two crosses were evaluated for three years at Palmer, Alaska. The distribution of lines for grain fill rate in the progenies was approximatel y normal. Heritability of grain fill rate was 89.6% in one cross and 90.0% in the other. Rapid grain fill rate was associated with shorter effective g rain fill period, longer time to heading, and higher grain yield, but not w ith time to maturity. Rapid grain fill rate appears to provide a means of i mproving grain yield without increasing time to maturity.