Abstract:
Water and nitrogen shortages in annual ryegrass (Lolium multiflorum) production can be improved by using proper
irrigation and nitrogen scheduling methods. The aim of this research was to analyse the effect of water and nitrogen
application on dry matter production and forage quality of annual ryegrass. Treatments consisted of three irrigation
levels, scheduling application to field capacity once every two weeks (W1), once a week (W2) or twice a week (W3),
and three nitrogen (N) levels, top-dressing after each harvest at a rate of 0 (N1), 30 (N2) or 60 (N3) kg N h−1 cycle−1.
Yield increased as a function of the amount of water and nitrogen fertiliser applied. The dry matter (DM) content,
in vitro organic matter digestibility (IVOMD), crude protein (CP) and metabolisable energy (ME) were higher in the
treatments being irrigated once every two weeks. These results conclude that higher irrigation coupled with high N
application significantly improved the dry matter yield, while water stress, to some extent, did improve the quality of
the pasture by increasing the DM content, IVOMD, CP and ME values.
