6.—(1) No certified seed potatoes certificate shall be issued by an authorised officer in the case of seed potatoes growing or grown in the protected region.
(2) No certified seed potatoes certificate shall be issued by an authorised officer in the case of seed potatoes growing or grown otherwise than in the protected region unless he is satisfied that in relation to the seed potatoes examined by him–
(a)(i)the land on which the seed potatoes are growing or were grown is land in respect of which a certificate issued under article 32(1) of the Plant Health (Great Britain) Order 1987 was in force at the time of the planting of the crop;
(ii)the land on which the seed potatoes are growing or were grown is land which has not at any time during the period of 4 years immediately preceeding the planting of that crop been used for growing potatoes;
(b)the seed potatoes have been produced from–
(i)basic seed potatoes; or
(ii)a crop grown with the authority of or in circumstances notified in writing as being acceptable to the Minister; or
(iii)seed potatoes grown elsewhere than in Great Britain and in respect of which an examination notified in writing as being acceptable to the Minister has been carried out;
(c)the seed potatoes in any one crop are of a single variety;
(d)the seed potatoes are taken from a crop of seed potatoes free from the following diseases or pests:–
Wart Disease (Synchytrium endobioticum (Schilb.) Perc.)
Potato Cyst Nematode (Globodera species infesting potatoes)
Ring Rot (Clavibacter michiganensis (Smith) Davis et al. ssp. sepedonicus (Spieck. & Kotth.) Davis et al.)
Brown Rot (Pseudomonas solanacearum (E. F. Smith) Jensen)
Potato Tuber Moth (Phthorimaea operculella (Zell.))
Potato Spindle Tuber Viroid
Colorado Beetle (Leptinotarsa decemlineata (Say))
Potato Tuber Eelworm (Ditylenchus destructor Thorne)
and is ascertained not to be affected by any of the diseases specified in column 1 below in excess of the tolerances respectively set out opposite each of these diseases in columns 2 and 3 below:–
| Column 1 | Column 2 | Column 3 |
|---|---|---|
| Diseases | Individual or Group Tolerances | Collective Group Tolerances |
| leafroll and severe mosaic (including tobacco veinal necrosis virus infection) | 2.0% | 5.0% |
| mild mosaic | 5.0% | 5.0% |
| blackleg | 2.0% |
(e)the seed potatoes are taken from a crop which on a sample is ascertained to contain not more than 0.5% of deviations from variety and type (rogues, undesirable variations, wildings and bolters) or groundkeepers, of which not more than 0.2% shall deviate from variety.
7. Seed potatoes shall not be classified as certified seed potatoes unless the immediately succeeding crop produced therefrom is likely to contain–
(a)not more than 0.5% by number of growing plants which deviate from variety and type of which not more than 0.2% shall deviate from variety; and
(b)not more than 10% by number of growing plants which show symptoms of severe virus diseases attributable to infection in the mother crop.
8. All certified seed potatoes shall be classified in a class known as the CC class.