ChileanJAR

The objectives were to characterize the structures of a Panicum coloratum L. cv. Verde pasture resulting from different forage accumulation periods, to assess if the rates of blade accumulation are constant on time, and to determine the variable (chronological or thermal time) best correlated to predict this process. The treatments were established by deferring the forage produced until the end of growing season, after cuttings performed in late spring, mid December (T₂₁₅), early January (T₁₉₀) and early February (T₁₆₀), and they were assigned randomly to paddocks of 0.5 ha each, with two replicates. Deferment period length did not affect (P > 0.05) total tiller density. The number of vegetative tillers was 31% higher (P < 0.01) in T₁₆₀ compared with T₂₁₅ and T₁₉₀. Total tiller mass was lower (P < 0.05) in T₁₆₀ than in T₂₁₅. Leaf blade mass was not different (P > 0.05) between treatments. The lower total tiller mass of T₁₆₀, together with a similar leaf blade mass in all treatments, resulted in a higher (P < 0.05) percentage of blades. The length of the deferment period did not modify (P > 0.05) either the number of leaf blades, or the percentage of living blades per tiller. The highest accumulation of live leaf blades was obtained at 50-60 days, or 600-665 degree - days. To obtain high forage yield and adequate nutritive value, the deferment period should not start until early February.