The Board of Regents of the University of Nebraska is authorized to enter into agreements with the owners of farms in this state for the leasing of testing centers. The farms chosen shall each be typical of the area selected as a location for such a testing center. The total area of each of such testing centers shall not be more than is adequate and necessary to best carry out the interest and purpose of sections 85-216 to 85-220. Upon such testing centers there shall be planted, cultivated and harvested, under the supervision and direction of the Department of Agronomy of the University of Nebraska, such crops as will, through experimentation, develop and demonstrate the best crops to be grown in such area and the best farm practices for use in connection therewith. Such agreements for the leasing of testing centers may provide for the performance of such work by the farm owner, in connection therewith, as may be deemed essential. They shall be entered into upon a year-to-year basis and contain a provision for renewal at the option of the Board of Regents.