Production and chemical composition of pasture forbs with high bioactive compounds in a low input production system in the Pacific Northwest

Abstract

Pasture forbs are increasingly being incorporated in pasture systems for their high nutritive value and biologically active secondary compounds as our understanding of their functional roles advances. A 2-year study investigated the effects of varietal differences and companion legume species on forage dry matter (DM) production, nutritive value, and plant secondary composition of two chicory (Cichorium intybus L.) cultivars (Antler and Grasslands Puna) grown in monoculture and in binary mixtures with red clover (Trifolium pratense L.) or birdsfoot trefoil (Lotus corniculatus L.). Antler chicory out-yielded Grasslands Puna chicory in the 2017/2018 growing season but the superiority of Antler was not consistent in 2018/2019. Binary mixtures of chicory and red clover consistently provided greater DM yield and higher nutritive quality forage than chicory monocultures. Intercropping birdsfoot trefoil with chicory cultivar Grasslands Puna yielded more DM in 2018/2019 and had lower NDF content in summer compared to chicory monocultures, but not when intercropped with Antler. Intercropping led to increased condensed tannin (CT) concentrations in forages as compared to monocultures. Antler chicory contained 7.3 times more (CT) compared to Grasslands Puna, but there was no significant difference in their anthocyanin concentrations.