Reddish brown powdery spots on my soybean leaves, leaves drying early, rust?

Reddish brown raised pustules on the leaf underside that shed a rusty powder when rubbed, with early yellowing and leaf drop in cool wet weather, is soybean rust. It moves fast in humid spells and can cause heavy loss if it reaches the pods filling stage, so act when you first see it. Remove and avoid volunteer soybean and alternate hosts nearby. Spray a recommended fungicide at first appearance and repeat as per label if wet weather continues, rotating fungicide groups so resistance does not develop. Triazole and strobilurin based products are commonly advised for rust, but follow the label dose and PHI and the local recommendation. For next year a tolerant variety and not too dense a canopy help. Confirm rust and the current fungicide with your KVK or UAS Dharwad, since the disease is most damaging in your higher rainfall belt.