The effect of perennial ryegrass sowing date on endophyte presence and dry matter yield

Abstract

The effect of perennial ryegrass sowing date on dry matter (DM) yield and endophyte presence in the resultant pasture was investigated in 2014. 'Trojan' perennial ryegrass with NEA2 endophyte was sown on three separate occasions (20 February, 20 March and 27 April 2014) into a Kaipaki peat loam soil in a replicated plot trial on a dairy farm near Cambridge, Waikato. The first two sowings were in dry conditions and neither showed any sign of germination until after 45 mm of rainfall on 4 April (43 days and 15 days after sowing, respectively). Endophyte infection in established plots was measured on 17 December 2014. Yield was also measured from sowing until no difference was seen between treatments, in October 2014. Percentage endophyte infection was not affected by sowing date. Establishment was significantly faster in the February and March sowings, prior to rain, and these produced ca. 2 t DM/ha more than the April sowing giving an estimated total profit advantage of $646/ha. Keywords: endophyte, Epichloë festucae var. lolii (formerly Neotyphodium lolii), perennial ryegrass, Lolium, seed storage, sowing date, NEA2