This study was conducter to determine the effects of time (autumn and spring) and dose (0, 4, 8 and 12 kg N/da) of nitrogen applications on seed yield and yield components of smooth bromegrass. The study was carried out under irrigated condi-tions in Erzurum, in crop seasons of 1986-1992. According to the mean of five years data nitrogen fertilization is recommended for high seed yield. Application of N as 4 kg/da in autumn+8 kg/da N in spring is effective for high seed yield (40.6 kg/da) and straw yield (959.8 kg/da) under irrigated conditions. The N application increased also generative shoots, seed weight and number per panicle and plant hight. Seed yield were positively correlated with number of generative shoots m 2 , straw yield, and plant hight.

This study was conducter to determine the effects of time (autumn and spring) and dose (0, 4, 8 and 12 kg N/da) of nitrogen applications on seed yield and yield components of smooth bromegrass. The study was carried out under irrigated condi-tions in Erzurum, in crop seasons of 1986-1992. According to the mean of five years data nitrogen fertilization is recommended for high seed yield. Application of N as 4 kg/da in autumn+8 kg/da N in spring is effective for high seed yield (40.6 kg/da) and straw yield (959.8 kg/da) under irrigated conditions. The N application increased also generative shoots, seed weight and number per panicle and plant hight. Seed yield were positively correlated with number of generative shoots m 2 , straw yield, and plant hight.