Need Urgent Help... Please Guide

Dear Sir/Madam

I am having a Joint account with my mother in Kotak Mahindra Bank with me as the primary/first holder. My mother is a family pensioner. She receive pension in SBI account which i transfer to Kotak account so that higher savings interest can be earned ( @ 6%) .Interest earned during F.Y. 2017-18 is Rs.40,282.00. Will this saving interest be taxable in the hands of my mother OR me as the primary holder?

Also, the account also give the facility of DEMAT Account(3-in-1 Trinity Account) and i am holding securities of Rs. 2 lacs where i am the primary holder of the account. What will be the tax liability in this case ?Will i have to file return since i am the primary holder? P.S. I have no source of income.

Please guide me