I think that you may mean mealy bugs, tiny furry looking insects that suck the sap of a plant, this can cause flowers and leaves to drop.
You could google it to see a photo

If the problem is on the roots in a small pot you can tip the plant out of the pot and remove as much compost as you can. Then paint all the white patches with methylated spirit and repot in a clean pot and fresh compost. If it is too big for this to be possible you can water it with a compound called Provado which is available in the UK but I don't know if you can get it in India.

If the mealy bugs are on the leafy part of the plant you can still paint them with methylated spirit. Make sure you paint both the bugs themselves and also the eggs, which look like fluffy bits of white cotton.