Father's 1/5th share with four sons is given to mother through VRO village records.

Which personal law applies in your case?

Are you all Hindu?

Who was 1st owner of the land amongst your forefathers?

How did the land devolve upon your father e.g; by inheritance, gift, WILL etc?

Or IT was self earned/acquired property of your father?

You have mentioned in query that “My father got 1.90 Acres as his 1/5th share with we 4 sons”

What exactly do you mean by IT? Is it that four sons’ names were also mentioned in land transfer document? Or It is just that your father has 4 sons and name of any son was not mentioned in land transfer document? 

Confirm!

Believing that you are all Hindu; If IT was self earned/acquired property of your father then in his life time your father could very well dispose IT in his life time by a valid/registered deed in favor of his wife………….e.g; gift/sale etc

The right to cultivate may not necessarily confer ownership on anyone cultivating the land.

Rest agriculture is state subject and the mater may be related with applicable LOCAL revenue codes/rules/laws.

You may obtain the mutation records with all link docs and show these to a very able senior LOCAL counsel of unshakable repute and integrity specializing in revenue/civil matters and well versed with latest citations, LOCAL applicable rules/laws/ … and having successful track record…. and worth his/her salt….. for a considered opinion to handle any situation…properly.

Check for such counsels at LOCAL O/o Tehsildar, Civil Courts, HC, SC…