'varietal list' means the list kept in terms of section 15; 'variety' means any plant grouping within a single botanical taxon of the lowest known classification, which grouping can be(a) defined by the expression of the characteristics resulting from a given genotype or combination of genotypes; (b) distinguished from any other plant grouping by the expression of at least one of the said characteristics; and (c) considered as a unit with regard to its suitability for being propagated unchanged. [Definition of 'variety' substituted by s. 1 (k) of Act 25 of 1996.] 2 Application of Act (1) The provisions of this Act shall apply with reference to any kind of plant which the Minister by notice in the Gazette declares to be a kind for the purposes of this Act. (2) Different kinds of plants may be thus declared with respect to different provisions of this Act. 3 Designation of registrar (1) The Minister shall designate an officer in the department as the Registrar of Plant Improvement, who shall exercise the powers, perform the functions and carry out the duties conferred upon, assigned to or imposed upon the registrar under this Act or, if he is designated under paragraph (a) (i) of section 24 (1), exercise the powers, perform the functions and carry out the duties conferred upon, assigned to or imposed upon the authority referred to in that section. [Sub-s. (1) substituted by s. 2 (a) of Act 39 of 1983.] (2) The registrar shall exercise his powers, perform his functions and carry out his duties subject to any instructions issued by the Minister. (3) (a) The registrar may authorize any officer or, with the approval of the Minister, a person who is not an officer, to exercise, perform or carry out any power, function or duty of the registrar. (b) Any decision made or order given by any such officer or person may be withdrawn or amended by the registrar, and shall, until it has been so withdrawn or amended, be deemed, except for the purposes of this paragraph, to have been made or given by the registrar.