اثر مقادير بذر، تاريخ كاشت در خزانه و نشاكاري بر عملكرد و ساير صفات برنج در منطقه لردگان

Effect of seed rate, planting date in nursery and transplanting date on yield and yield components of rice (Koohrang cultivar)

This study was carried out in order to determine yield, and other traits in Champa rice cv. Kohrang as affected by seeding rate,planting date in the nursery and date of transplanting in Lordegan region in 2000 and 2001. The experimental design was split plot with 3 replications. The main plot included date of transplanting. The combination of two other factors, seeding rates and planting dates (factorial) was assigned to the sub plots. The rates of seeding were 60, 80 and 100 kg/ha. Different planting dates in the nursery were 21 April, 30 April and 10 May 2000 and 2001 cropping season. Transplanting was carried out in 8, l8and 28 June in 2000 and 2001 cropping seasons. Results indicated that there was no significant difference between years for paddy yield, but the difference between seeding rates was 80 kg/ha. The effect of planting date in the nursery was highly significant (p < 0.01) and the maximum yield was produced in the second planting date (30 April). The effect of transplanting date was also highly significant (p < 0.01). The best transplanting date was 18 June, with paddy yield of 5840 kg/ha. Growing Degree Days (GDD) and days to 50% flowering reduced with delay in planting date in nursery, it increased with late transplanting date. The effects of seeding rates on yield components were low, however, planting date in nursery and transplanting date had greater effects on this characteristics.