White raised blisters on my mustard leaves and swollen stalks, what disease?

Shiny white raised pustules on the leaf underside with yellow patches above, plus swollen twisted flower stalks bent into a stag head with no pods, is white rust, often together with downy mildew, which makes the stag head deformity. It spreads in cool humid weather and dew, and the stag heads carry the disease, so cut and destroy them. Remove infected debris and follow a rotation away from mustard family crops. A recommended fungicide seed treatment at sowing reduces early infection, and a foliar fungicide at first symptoms with a repeat as per label helps in wet spells, rotating fungicide groups. Metalaxyl and mancozeb based products are commonly advised for this complex, but follow the label dose and PHI and the local recommendation. For next year a tolerant variety and timely sowing reduce it. Confirm the disease and fungicide with your KVK or CCS HAU Hisar, which is in your district.