R. Bras. Zootec.01/Nov/2008;37(11):1940-6.
Response of perennial pasture to fertilization with pig slurry: cv. Tifton 85
DOI: 10.1590/S1516-35982008001100006
The work was carried out with the aim to verify the response of a cv. Tifton 85 pasture, in Depressão Central of Rio Grande do Sul state, to pig slurry (PS) fertilization, in the rates of 0, 15, 30 and 45 m3/ha/cutting, between October/03 and February/04, totalizing 0, 60, 120 e 180 m3/ha in the spring-summer. The PS was applied after cuttings, in: 15/10/2003 (uniformizing cutting), 11/24/2003, 1/10/2004 and 2/5/2004. The last cut was done in 4/10/2004 and then it was not applied PS. The highest production (2,232 kg DM/ha) was obtained in the second cutting (January/2004), with 30 m3/ha, a 347% higher than control. The total DM production response as function to PS was quadratic, being obtained 1,397 (without PS), 2,971 (15 m3), 4,696 (30 m3) and 4,714 (45 m3) kg/ha. The PS efficiency did not differ between the rates (24,5 kg DM/m3/ha) but it varied between cuttings, from 5.6 a 49.7 kg DM/m3/ha. The highest N extraction was 28 kg N/ha (30 m3) and the N recovery varied from 2% (fourth cutting) to 12% (second cutting). The CP and ADF content were affected by fertilization and cutting date, varying between 8.3 (without CS) to 10.7% (30 m3) in the first cutting and 45.9 (without PS) to 42.8% (45 m3) in the last cutting, respectively. The PS application is an alternative to increase the pasture production of cv. Tifton 85, being suggested the 30 m3/ha/cutting as reference-value.
Keywords: chemical composition; Cynodon; manure; nitrogen