Two natural pasture productivity in the dryland area. IX Region

Rolando Demanet F.1, Rodrigo Contreras O.1 y Mauricio Hiriart L.1

In order to quantify total production, annual dry matter distribution, quality, fertilizer application and remainder on productivity and to determine the effect of management on the production of natural pasture, an experiment on two locatities with andisol soils (San Ramón) and ultisols soils (Tromén) in the dryland Central Valley of the IX Region was developed. A divided blocks design with three repetitions was utilized. The main parcel considered the following treatments: natural pasture infertilized (PN) and natural pasture fertilized (PNF), in each treatment the effect of remainder days and time to the first utilization was also analyzed. Fifty, 30.6 and 10 kg ha-1 of NPK and 60, 30.6 kg and 60 kg ha-1 of NPK were applied in San Ramón and Tromén, respectively. A marked seasonality of forage production was presented and the maxinum dry matter accumulation was in mid summer (december-january). The botanical composition varied with gramineae being the main component, specially Agrostís capillaris. Fertilization produced a significant improvement (P < 0.01) in dry matter production with 44.7% and 138% for the andisols and ultisols soils, respectively. During the vegetative stage, utilization time did not change the total forage production of the season. However, prolonged remainder allowed a nigher dry matter accumulation but a decrease in the regrowth capacity of the pasture was presented. Utilization strategy did not change (P > 0.01) the productivity of the pasture in the following season.

Keywords: natural pasture, management, fertilization, productivity, dryland area.
1 Estación Experimental Carillanca (INlA). Casilla 58-D. Temuco. Chile.