Racial discrimintion and mental harassement at workplace

Only a collective action against the 'boss' can save the situation you described. If it is a private company, then you can make the management talk to unions. If you have no proof of discrimination, then you cannot approach the labour department. 

The boss is not having very good reputation in market.He always had issues in all the companies where he worked.The employees were discriminated and many ppl from south india were not promoted and north indians were given promotion.Many ppl have also complained abt his misbehaviour and the mgmt enquired abt his misbehaviour form diff ppl,and everytone told the same thing.There is some problem with his attitude.In this case what can be done..?

This is an issue with the attitude of one individual at the work place. I think it is more a management's problem. Our law is very conventional and you need irrefutable proof to initiate legal measures.

have you or your batch of effected employees have given any written representation to the management and what thus the management say about the enquirey in writting thus they had given because that proof is enough if the management is in your favour and for this attitude of your boss you or your batch of employees can meet your union and take their assistance and they will reprsent on your behalf even your batch wants to contest the case