Persistence of perennial ryegrass, tall fescue and cocksfoot following annual sowings: influence of grass species, ryegrass cultivar and pasture age on yield, composition and density

Persistence is an important component of perennial pasture-grass productivity. Defining traits that affect persistence essential for improving pasture longevity through plant breeding and identifying should be included in cultivar ranking indices. Compared with conventional longitudinal studies, where a single sowing monitored over time, repeated annual sowings allow the effects on year ensuing interactions between environment age to identified. An experiment was commenced 2015 under sheep grazing Canterbury 2016 cattle Waikato, eight cultivars ryegrass representing different ploidy, flowering date, (release date), one each tall fescue cocksfoot were sown four randomised complete blocks autumn year. This paper reports interim data spring yield, composition, density 3-year-old, 2-year-old 1-year-old pastures exposed same environmental conditions within same, There significant botanical basal cover tiller due cultivar, age, their interaction. When confounding effect year-to-year variation removed by comparing cohort year, underlying differences among grass species cultivars, ages pasture, starting reveal nature this influence persistence.