Pasture production and botanical composition of high sugar and control ryegrasses with or without endophyte under irrigation in Canterbury

Abstract

High sugar grasses and novel endophytes are two new technologies promoted for pastoral farmers. While assessing their value for pastoral farming it is important to consider the interactive effects of these technologies on both pasture production and composition. Pasture production and botanical composition was measured over 2 years for a range of perennial ryegrass cultivars infected with different endophyte strains in grazed small plot trials under irrigation in Canterbury. Cultivar and endophyte strain had little effect on total dry matter production; agronomically the UK-bred high sugar grass performed as well as the New Zealand controls. There was a trend for less white clover with ryegrass cultivars infected with AR1 and AR37 endophyte compared with endophyte-free treatments. Generally, endophyte infection is promoted as being beneficial for ryegrasses. However, under irrigated conditions and low levels of insect pressure, the advantage of endophyte infection was minimal.