Prima facie, from what is narrated above, I do not see any problem regarding this. Original sale or partition or transfer document, Original parent document, NIL encumbrance certificate for more than thirty years, latest tax paid receipt etc. are the normal requirements to show the title to a property.
However if there are any special local laws and regulations regarding agricultural lands, then I cannot say on that.
Moreover, to satisfy yourselves beyond doubt, you may also show the documents to a known and experienced layer and get his opinion. The fee may be normal and affordable and it is worth paying. If you don't know such a lawyer, you can approach a commercial bank who give loans against property .They will have lawyers for their matters. You can use his service paying the fee.