7.—(1) Subject to sub-paragraph (2), in the case of a hybrid of barley, durum wheat, oats, self-pollinating triticale, spelt wheat and wheat, the minimum varietal purity shall be 90% in the case of CS seed.E+W
(2) For the purposes of sub-paragraph (1), the minimum varietal purity of seed shall be examined mainly in official post control tests on an appropriate proportion of samples.