Response to calcium carbonate and to phosphate fertilization, of the mixture perennial ryegrass-white dover, on an Andisol. Production and botanical evolution

Ricardo Campillo R.1

The effect of four levels of phosphorus (0, 33, 66 and 98 kg/ha), and four levels of calcium (0, 0.4, 0.8, and 1.6 ton/ha) on a perennial ryegrass and white dover mixture, was studied at the Carillanca Experimental Station (INIA, Temuco), during two years. The trial was sown in September, 1985, in a complete randomized blocks desing, with four replications. Each plot consisted of 5 rows, 6 m long, 20 cm apart. Perennial ryegrass ev. Nui was sown with 18 kg of seed/ha and white dover ev. Huia, at 3 kg seed/ha, previously inoculated with the specific Rhizobium and pelletized. Plant population, nodules/clover plant, dry matter production, composition of the pasture through time, soil pH, and residual phosphorus at the end of each growing season, were measured. No significant differences (P > 0.05) were found in plant population and nodules/plant. ln both sea sons, dry matter production increased significantly (P < 0.01) as a result of phosphorus applications. However, calcium carbonate and seed pelleting showed no effects. Phosphorus applications influenced positively dover population and residual phosphorus, at the end of each growing season.

1 Estación Experimental Carillanca (INIA), Casilla 58-D, Temuco, Chile.