Hi Nalina,
Yes you can join for MA in Journalism after B.SC degree, some of the colleges admit students from different streams.
Usally an BA journalism student with minimum 50% marks are preferred.
Some of the colleges has entrance exam for P.G, for getting admission.

Some of the best colleges in India for P.G in Journalism are

• Sri HK Arts college, Gujarat
• Symbosis College of Arts and Commerce,Pune
• St.Joseph College, Devagiri
• Kristu Jayanti College, Bangalore
• Christ College, Bangalore
• Delhi College of Arts and Commerce
• Kishinchand Chellaram College
• Lady Shi Ram college
• Kamala Nehru College
• Madras Christian College

Hope you get it, all the best for your studies.
Thank you