Abstract
The efficiency of minerals for ruminants differs according to the kind of minerals and forage species. A possible factor causing this difference is the association between the efficiency of minerals and the digestibility of tissues where the minerals exist. The purpose of this experiment is to investigate the distribution of macrominerals in different tissues of tall fescue. A leaf blade of tall fescue cultivar 'Hokuryo' was taken from a flag leaf on June 30, 1992. Nine units - from 3 parts of 3 leaf sections - were investigated. Relative percentages of 7 mineral elements were determined quantitatively in 6 different tissues per unit using energy-dispersive X-ray analysis. In each unit, silicon and potassium (K) were the most predominant elements, followed by chlorine (Cl), calcium (Ca), sulfur and phosphorus ; a small amount of magnesium was also detected. Silicon existed mostly in epidermal structures. Although the other minerals were distributed generally throughout the sectional area, Ca was abundant at the developed secondary cell walls, and K and Cl were especially higher in vascular tissues. The low efficiency of ca is partially caused by the distributional pattern, and was abundant at developed secondary cell walls. However, no distributional relationship was observed for the other minerals.
