21.—(1) A rootstock not belonging to a variety may be certified as certified material if it meets the requirements in sub-paragraph (2).
(2) The requirements are that the rootstock—
(a)is grown from a certified mother plant grown from pre-basic or basic material;
(b)is true to the description of its species;
(c)complies with the time period referred to in paragraph 8(4);
(d)complies with the requirements concerning defects in paragraph 12;
(e)complies with the health requirements in paragraph 22; and
(f)has been grown in soil that is found by sampling and testing, to comply with paragraph 223.
(3) Where a rootstock not belonging to a variety is a certified mother plant or certified material that no longer fulfils the requirements in sub-paragraphs (2)(b) (e) the supplier must—
(a)remove the rootstock from the vicinity of other certified mother plants and certified material; or
(b)take appropriate measures to ensure the rootstock complies with those requirements again.
(4) A supplier may use any rootstock removed in accordance with paragraph (3)(a) as CAC material provided the rootstock fulfils the requirements set out in Schedule 1 for CAC material.
(5) For the purpose of this paragraph, any reference to pre-basic mother plants or to pre-basic material in paragraphs 8(4) and 12 is to be construed as reference to certified mother plants or, as the case may be, to certified material.