Cultivar and year effect on grain filling of winter barley.

Pržulj Novo

Abstract

Kernel weight and grain yield depend on the rate and duration of grain filling (GF). Rate of GF represents the rate of dry matter accumulation per kernel and GF period duration from anthesis to physiological maturity. In order to study the relationships among grain yield and yield components and the rate and duration of GF in winter barley, field experiments were conducted during the 1995-1998 period. A quadratic polynomial was used to describe the relationship between kernel weight and time from anthesis and a linear equation to describe the relationship between kernel water content and time from anthesis. Accumulated growing-degree days (GDD) from anthesis were used as a time scale. The rate and duration of GF were obtained from the fitted curve. Depending on the cultivar and year, rate of GF ranged from 0.058 to 0.082mg kernel^–1 GDD^-1 and the duration of GF from 505 to 887 GDD. Rate positively (r=0.70) and duration of GF negatively (r=-0.57) effected grain yield. Both rate and duration of GF to a large extent were influenced by environmental factors. The correlation between rate and duration of GF was negative. The positive correlations between the rate of GF and kernel weight as well as kernel weight and yield enable indirect selection for yield and a high rate of GF via breeding for a larger kernel.