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

摘要

High sugar grasses and novel endophytes are two newtechnologies promoted for pastoral farmers. Whileassessing their value for pastoral farming it is importantto consider the interactive effects of these technologieson both pasture production and composition. Pastureproduction and botanical composition was measuredover 2 years for a range of perennial ryegrass cultivarsinfected with different endophyte strains in grazedsmall plot trials under irrigation in Canterbury. Cultivarand endophyte strain had little effect on total dry matterproduction; agronomically the UK-bred high sugar grassperformed as well as the New Zealand controls. Therewas a trend for less white clover with ryegrass cultivarsinfected with AR1 and AR37 endophyte comparedwith endophyte-free treatments. Generally, endophyteinfection is promoted as being beneficial for ryegrasses.However, under irrigated conditions and low levels ofinsect pressure, the advantage of endophyte infectionwas minimal.