In vitro Dry Matter Digestibility in Timothy (Phleum pratense L.) Cultivars of Different Maturity1

Abstract

Ten named timothy (Phleum pratense L.) cultivars varying in maturity were compared to common timothy for in vitro dry matter digestibility (IVDMD) in 1973 and 1974. Early cultivars had significantly higher IVDMD at early heading compared with later maturing cultivars. The lower IVDMD of later‐maturing cultivars at early heading was offset by the slower daily decline in IVDMD. At early anthesis there was little difference among cultivars in IVDMD. The time interval between early heading and early anthesis varied from 11 to 16 days for the earliest and latest maturing timothy cultivars, respectively. Days from initial heading to initial anthesis was highly correlated (r = −0.71) with daily decline in IVDMD. Results indicate selection for relatively early maturity at initial heading should improve chances for increased IVDMD in timothy.