Question: asking about growth of seedling in nursery bed.

Answer: 

 keep monitoring the seedling for any disease or pest in nursery bed. 
fertilizer is recommended in main field 3-4 days before transplanting.
age of the seedling must be 25-30 days in nursery bed.

nitrogen is applied for vegetative growth therefore application of fertilizer in nursery bed is not necessary , dry cowdung is recommended at seedling stage.
growth can be monitored on main field after transplanting.