The experiment RO the effects of density and nitrogen fertilizer on growth, development and productivity of rice variety BT13 was arranged split- plot method with three replicates in 2012 and 2013. The experiment was arranged as follows: 4 trabsplanting density (Ml: 30 plants/m2
M35 plants/m2
M40 plants/m2
M50 plants/m2 and 3 levels of applied nitrogen (P8 tons of organic fertilizer + 80 N + 90 P2O5 + 60 K2O
P8 tons of organic fertilizer + 100 N + 90 P2O5 + 60 K2O
P8 tons of organic fertilizer + 120 N + 90 P2O5 + 60 K2O) (in which the is control (P2) is the local fertilizer method). The results show that (1) variety BTl3 is early maturity rice (98 days in auturm and 124 days in spring)
(2) sparse density of transplanted rice at 8 tons of organic fertilizer + 120 N+90 P2O5+60 K2O and transplanting density with 30 plants/m2 in autumn crop, and at 8 tons of organic fertilizer + 100 N + 90 P2O5 + 60 K2O and transplanting density with 30 plants/m2 in spring crop are achieved a higher number of effective panicle in comparison to the high density at formula: 8 tons of organic fertilizer + 80N + 90 P2O5 + 60 K2O and transplanting density with 50 plants/m2 in autumn crop, and at formula: 8 tons of organic fertilizer + 100 N + 90 P2O5 + 60 K2O and transplanting density with 50 plants/m2 in spring crop
(3) formula 8 tons of organic fertilizer + 120 N + 90 P2O5 + 60 K2O and transplanting density with 50 plants/m2 severe pest infestation than formula (8 tons of organic fertilizer + 80 N + 90 P2O5 + 60 K2O and transplanting density with 30 plants/m2, especially, for sheath blight, this formula recipe prevalence was 6 percent, while formula 8 tons of organic fertilizer + 120 N + 90 P2O5+ 60 K2O and transplanting density with 50 plants/m2 is infested at 40 percent in automn season
and similarly infected in the spring
(4) in both crops, the formula 8 tons of organic fertilizer + 80 N + 90 P2O5 + 60 K2O and transplanting density with 35 plants/m2 gets the highest yield 6.9 tons/ha in automn and 7.22 tons/ha in spring. This formula not only reduces the amount of nitrogen (20 kg N/ha) but also yields higher than the current level of intensification.