Yield and quality of Lolium perenne L. pastures under irrigation in the Southern Zone of Chile

Abstract

The objective of this work was to study the effect of irrigation on yield and quality of Lolium perenne L. pastures at Southern Chile. The trial was carried out at Cocule, Río Bueno, Los Ríos Region, between November 1st 2012 and April 30Th 2013. Measurements were taken at two sectors, A and B. The unirrigated treatments (control) received water from precipitation (475 mm), and the irrigated treatments received water from precipitation and a central pivot system (895 and 920 mm for sector A and B, respectively). Irrigated treatments were located under the pivot, whereas unirrigated treatments were located 40 m from the pivot. Three sample plots of 10 x 10 m were established at each treatment. Pastures were grazed by dairy cows and dry matter production was estimated by a pasture plate meter with 100 observations per plot. Nine grazing events were conducted during the study period and before each grazing forage samples were taken from the plots to determine dry matter (DM), crude protein, metabolizable energy, neutral detergent fiber and in vitro digestibility. Tiller density was measured on April, at the end of the sampling period. Results showed significant differences on dry matter production with an increment of 3 to 4 ton DM ha-1, as effect of irrigation. Tiller density and nutritive value increased significantly in irrigated pastures.