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)complies with the time period specified in paragraph 8(3)(b);
(c)complies with paragraph 12 concerning defects;
(d)complies with the health requirements in paragraph 22; and
(e)is grown in soil that is found, by sampling and testing, to comply with paragraph 23.
(3) For the purpose of this paragraph, any reference to pre-basic mother plants or pre-basic material in the paragraphs mentioned in sub-paragraph (2) is to be construed as reference to certified mother plants or certified material, as the case may be.
(4) Where a rootstock not belonging to a variety is a certified mother plant or certified material that no longer fulfils the requirements referred to in sub-paragraph (2), the supplier—
(a)must remove the rootstock from the vicinity of other certified mother plants and certified material;
(b)may take appropriate measures in order to ensure the rootstock complies with those requirements again.
(5) A supplier may use any rootstock removed in accordance with sub-paragraph (4)(a) as CAC material provided the rootstock fulfils the requirements set out in Schedule 1 for CAC material.