Yield of Tifton 85 grass under irrigation and nitrogen doses

The study was conducted on a dairy farm in the municipality of Xambre, Northwest region of Parana, in the period from March 2011 to February 2012 to evaluate the yield and botanical composition of Tifton 85 with and without irrigation under nitrogen doses. The experimental plots were implanted in completely randomized blocks with and without irrigation and subplots through four nitrogen levels: 0, 20, 40 and 60 kg ha(-1) per grazing cycle, with four replications. The yield in dry matter (DM) was higher under irrigation, responding linearly to increasing nitrogen fertilization. At a dose of 60 kg N ha(-1) yields of 39279 and 27826 kg DM ha(-1) were obtained, with and without irrigation, respectively. The leaf stem ratio was not affected by irrigation. The overall mean percentage of dead material with and without irrigation was equal to 13 and 17%, respectively.