Currently my wife is visiting India, and she can come back only next month.
With this situation can I file my 485 papers now,
----YES
and later once she comes back in July file her papers?
-----Yes if your PD remain current( if PD not current she will not be able to file her I-485 and you need to be on H1 status and she on H4 status till the PD becomes current to file her I-485)
If I file separately what could be the delay in getting approvals?
------------USCIS may not attach her I-485 to your I-485 file