EFFECT OF NITROGEN RATE ON BREEDER SEED PRODUCTION OF RICE (ORYZA SATIVA L.)

The experiment was conducted at BRRI farm, Gazipur to observe the effect of nitrogen rate for Breeder Seed production of rice. For this, BRRI dhan34, BRRI dhan37, BRRI dhan38 and BRRI dhan31 as check during T.Aman 2006-07 with six nitrogen treatments, viz. T₁ (Control, i.e. no fertilizer), T₂ (60 % less from T₅, i.e. 18.4 kg N/ha), T₃ (40 % less from T₅, i.e. 27.6 kg N/ha), T₄ (20 % less from T₅, i.e. 36.8 kg N/ha), T₅ (46 kg N/ha i.e. 100 kg urea/ha), T₆ (20 % excess from T₅,  i.e. 52.2 kg N/ha) were transplanted. In the experiment, significant differences among the varieties were observed for all the characters and among the treatments it was observed only for yield per hill (g). However, T₃ (27.6 kg N/ha) and T₄ (36.8 kg N/ha) treatments showed no significant difference from T₂ (18.4 kg N/ha), T₅ (46 kg N/ha) or T₆ (52.2 kg N/ha) treatments except for effective tiller number (8.33) for T₂ (18.4 kg N/ha) and lodging score (0.23) for T₅ (46 kg N/ha) in BRRI dhan34 and 1000 grain weight (15.3 g) and yield per hill (12.87 g) for T₂ (18.4 kg N/ha) in BRRI dhan37, respectively and germination percent (67.47) for T₃ (27.6 kg N/ha) in BRRI dhan38. Since lodging can deteriorate seed quality therefore, T₄ (36.8 kg N/ha) treatments for BRRI dhan34 and T5 (46 kg N/ha) for BRRI dhan37 or BRRI dhan38 can be recommended.