Sections 501B.16 to 501B.23 do not apply to trusts in the nature of mortgages or to trusts commonly known as voting trusts. Sections 501B.16 to 501B.23 apply, however, unless otherwise provided in the trust instrument, to trusts established in connection with bonds issued under chapter 469, and, at the sole election of the issuer of bonds issued under chapter 469, without a trust indenture, to the pledges and other bond covenants made by the issuer in one or more resolutions with respect to the bonds. If the issuer so elects to apply sections 501B.16 to 501B.23, for such purposes only, the pledges and other bond covenants shall be deemed the "trust," the resolution or resolutions shall be deemed the "trust instrument," and the issuer shall be deemed the "trustee" notwithstanding the absence of any fiduciary responsibility owed by the "issuer" toward the bondholders. Nothing in this section shall preclude the issuer from seeking approval under sections 501B.16 to 501B.23 of the creation of any express trust under a trust indenture and the appointment of a trustee thereunder to act as a fiduciary for the benefit of the bondholders. As used in sections 501B.16 to 501B.23, "person" includes an artificial as well as a natural person, and "beneficiary" includes a bondholder.