The tissue proportion and cell wall thickness are important anatomical traits influencing nutritive value of grasses. Theses characteristics present high correlation with fiber, lignin and crude protein (CP) contents and in vitro dry matter digestibility (IVDMD) coefficients. The tissues lowest digested correlate negatively with CP and IVDMD and positively with fiber and lignin contents, while the tissues rapidly digested show positive correlation with CP and IVDMD and negative with fiber and lignin contents. The digestion of some tissues is limited not only by negative effect of lignin on the cell wall digestion, but too by compact organization of cells of some tissues and by high cell wall thickness. The relationships between plant anatomy and nutritive value highlight the possibility of utilization of anatomical traits in evaluation of forage grass nutritive value.
anatomical traits; tissue digestion; cell wall thickness; tissue proportion