EFFECTIVENESS OF ONE CYCLE OF PHENOTYPIC SELECTION FOR IN VITRO DIGESTIBILITY IN BROMEGRASS AND ORCHARD GRASS

Abstract

Twenty-seven topcross and nine polycross progenies of bromegrass (Bromus inermis Leyss) were evaluated for in vitro digestibility (IVD) and yield. Two groups of polycross progenies of orchard grass (Dactylis glomerata L.) were also evaluated. Bromegrass plants varied in IVD from 58 to 70%, while their topcross progenies varied from 58.2 to 64.6%. The correlation between parents and progeny was 0.55. Selection for high IVD did not result in any improvement over cv. Saratoga. One group of 10 orchard grass plants was high in IVD (62–66%), while the other was low (50–58%). The polycross progenies of these two groups were similar (68.2% vs. 68.5%). Selection for IVD was not effective in altering progeny IVD values.