I have a verbal lease with a tenent for ex amount of dollars to rent a irrigated farm and the tenent came to me and said he gets to rent the farm for way less money and I have to rent it to him. I think our verbal lease mean he get to rent it only if he pays the same rent as last year or I am free to rent it to some one else. Who is right?

Don't know what your tenant is referring to, but a verbal lease can be binding if proven.

That you are the owner of the property. Your tenant can't use the property except under the terms YOU allow.

Did the tenant point to any law that backs up his claim? Assuming rent is due monthly, if he gives you a check for anything less then the amount you had previously agreed to, do not cash the check (or accept any cash). But give him a pay or quit notice as the first step in eviction. Check the laws in your area for the exact eviction process.

Unless you are renting some specificly government controlled crop harvest land, ( and I am not sure they control the rent amount) but you can charge what ever rent you want,

Next I would never do anything verbal, change this year to a written lease to protect yourself