I see on web that I can gift upto $12K per individual in India. Is this limit valid for blood relations as well? Can I transfer around $50K in my mother's account?
There are many variables to this. The service provider you use, the limits they set and of course the limit on the total amount that can be transferred set by the IRS
From the US perspective you can give away up to 2.5 mill $ before they would ask you to pay tax. 12k$ / year unreported. It's India that might ask for taxes from your mom. Wire transfers for cases like this are safer.
Transfer to your parents has no tax India
Yes I did that last year! Better still - open an NRE account in India and ask them to use it. They get a debit card too. Interms of tax implications. There isn't any as it is already taxed money. If you transfer to your mom. She might have to pay tax on that in India. So the NRE route is easier and safer!
Which bank is good for NRE?
SBI, HDFC, Yes bank. Incase you have trouble getting a notary signature. Just go to SBI California, the bank manager helps with that.