Question: asking about control of insect infestation before transplanting to main field
Answer: root dip treatment of seedlings: the uprooted seedlings are washed and then the root portion is dipped in solution of chlorpyriphos (2 ml/lit of water) along with 1% urea (10g/lit of water) for 3 hours as protective measure against stem borer, gall midge and hoppers. alternatively  phorate or diazinon 1g/sq.m is to be applied in the seed bed 5 to 7 days before uprooting of seedlings or spray chlorpyriphos 20 ec @ 0.02% in the seed bed 5-7 days before uprooting.