Custody of girl infant aged one and half year.

My wife left abandoned my one and half year old girl child at the doorsteps of the police Station where she filed a 498A complaint against me, my mother and father. That complaint was investigated by police and found to be false. I have taken a copy of that report through RTI. However, the investigated officer, who was a lady officer, asked my wife to take custody of the girl child but she refused to do so, and the IO handed over this infant daughter to me. My wife is working in a govt. office on contract basis and getting Rs 17500 per month as salary. I am filing a divorce petition on account of cruelty on the part of my wife, and also claiming maintenance for the looking after of my daughter. Can my wife now claim custody of my infant daughter? I am also a govt. official, but, presently undergoing training and getting a stipend of Rs 10,000 per month. I will get regular appointment on completion of training within next two or three months. My pay at that point of time will be around 20,000 per month. Could you please guide me.