Resumen

JAHN B., Ernesto; AVILES R., Rodrigo  y  BARRALES V., Luis. Drying rate of alfalfa under different conditions of artificial drying. Agric. Téc. [online]. 2004, vol.64, n.2, pp. 163-171. ISSN 0365-2807.  doi: 10.4067/S0365-28072004000200005.

The objective of the present study was to determine the drying rate (TS) of alfalfa (Medicago sativa L.), simulating under laboratory conditions different temperatures, ventilation rates and swath densities. The alfalfa pasture was harvested manually and the samples obtained were placed in ovens with and without forced ventilation, at three densities: 4.78, 3.62, and 2.17 kg m^-2, and three temperatures: 20, 30 and 40ºC. Eighteen treatments were evaluated with four replicates; DM was determined every 3 h during the day and treatments were evaluated for 53 h. Six ovens were utilized. Increasing forage density produced a reduction in TS (P < 0.0001), as well TS increased with the increase in temperature and ventilation. TS was 1.83, 2.20 and 3.25% DM h^-1 for forage densities of 4.78, 3.62 and 2.17 kg m^-2, respectively, when the temperature was 30ºC. TS was 1.49, 2.20 and 3,11% DM h^-1 for temperatures of 20, 30 and 40ºC, respectively, when the forage density was 3.62 kg m^-2. Ventilation increased TS between 2 and 2.5 times depending on oven temperature. As forage DM increased, TS decreased. The data obtained under laboratory conditions are useful to elaborate simulation models since they permit to study different climatic factors without interactions between them.

Palabras clave : Medicago sativa L.; drying rate; temperature; forage density.