4.—(1) No growing crop certificate may be issued containing a statement that seed potatoes are capable of being marketed as pre-basic seed potatoes of any grade unless the authorised officer is satisfied that the land on which the seed potatoes are growing or were grown—
(a)is land which, as a result of a soil test carried out by the Welsh Ministers prior to the planting of the crop, has been found not to be contaminated with Potato Cyst Nematode (Globodera species infesting potatoes);
(b)is not demarcated under Schedule 15 to the Plant Health (Wales) Order 2006 as infested with a European population of Potato Cyst Nematode; and
(c)has not been used for growing potatoes at any time during the seven years immediately preceding the planting of the crop.
(2) But sub-paragraph (1)(a) does not apply in the case of seed potatoes grown in a soil-free medium.
5. No growing crop certificate may be issued containing a statement that seed potatoes are capable of being marketed as pre-basic seed potatoes of Union grade PBTC unless the authorised officer is satisfied that the immediately succeeding crop produced from the seed potatoes is not likely to contain—
(a)plants of a different variety; or
(b)plants affected by mild or severe virus.
6. No growing crop certificate may be issued containing a statement that seed potatoes are capable of being marketed as pre-basic seed potatoes of Union grade PB unless the authorised officer is satisfied that the immediately succeeding crop produced from the seed potatoes is not likely to contain—
(a)more than 0.01% by number of growing plants which deviate from variety and type or are a different variety; or
(b)more than 0.5% by number of growing plants which show symptoms of virus diseases where those symptoms are attributable to infection in the mother crop.