When bonds are issued, the taxes upon which they are based and by which they are secured shall, when and as collected, be kept by the treasurer and used solely for payment of the bonds and interest thereon, until all of the bonds, together with the interest, are paid in full. The treasurer may pay the interest on the bonds from the general fund. No interest shall be paid on any bond for any period after the date it is payable or after the date the treasurer calls the bond for payment, whichever date is later.