Question: asking about varieties ,seed requirement of mustard 

Answer: varieties like tm-2 (105-115 days) ,tm-4 (105-115 days),barun (110-120 days),pm-26 (110-120 days), pm -27 (105-115 days).
seed rate: 1.3-1.5 kg/bigha
seed treatment: seed treatment with metalaxyl 35 ws @ 6 grams per kg of seed make free  against fungal disease like downey mildew and white blast
lime application in :  dolomitic lime @ 65 kg /bigha should be applied 15 days before sowing and mixed properly with soil for the land where more than one crops are grown in a year.