SCHEDULE 4Grading of seed potatoes

PART 1Seed potatoes capable of being marketed as pre-basic seed potatoes

In the course of making a determination for the purposes of paragraph 1(b) of Schedule 1, where an authorised officer determines that seed potatoes are capable of being marketed as pre-basic seed potatoes, that officer may grade them as being seed potatoes of any of the Union grades specified in column 1 of Table 1 where that officer is satisfied following inspection that the requirements specified in column 2 in relation to that grade have been met and that the tolerances specified in column 3 have not been exceeded in respect of those seed potatoes.

Table 1

Column 1

Column 2

Column 3

Union grade

Requirements

Tolerances

PBTC

(1) The seed potatoes must—

Nil

(a) be derived from nuclear stock or tested tubers—

(i) that are free from Pectobacterium spp., Dickeya spp., potato viruses A, M, S, X, Y, leaf roll, potato mop top virus, tobacco rattle virus and tobacco venial necrosis or any other significant virus; and

(ii) supplied by a source acceptable to the Secretary of State, which have been grown on a unit where no material of the species Solanaceae or other material, other than that derived from nuclear stock or tested tubers from a source acceptable to the Secretary of State, has been grown;

(b) have been kept free from—

(i) potato viruses A, M, S, X, Y, leaf roll, potato mop top virus, tobacco rattle virus and tobacco veinal necrosis or any other significant virus;

(ii) witches’ broom and blackleg;

(iii) deviations of variety and type; and

(iv) groundkeepers;

(c) have been produced (in the case of plants and tubers) through micro-propagation in a protected facility and in a growing medium that is free from pests; and

(d) (in the case of tubers) not been multiplied beyond the first generation.

PB

(1) The seed potatoes must be derived from—

(a) nuclear stock or tested tubers—

(i) supplied by a source acceptable to the Secretary of State, which have been grown on a unit where no material of the species Solanaceae or other material, other than that derived from nuclear stock or tested tubers from a source acceptable to the Secretary of State, has been grown; and

(i) Blackleg - nil

(ii) that are free from Pectobacterium spp., Dickeya spp., potato viruses A, M, S X, Y, leaf roll, potato mop top virus, tobacco rattle virus and tobacco venial necrosis or any other significant virus; or

(ii) Not true to type or of a different variety, including groundkeepers 0.01%

(b) a stock graded as Union grade PB of a previous field generation in the year preceding the planting of the crop; or

(iii) Potato viruses Y, A and leaf roll - nil

(c) such other seed potatoes as are notified in writing by the Secretary of State as being acceptable to the Secretary of State.

(iv) Other mosaic viruses 0.1%

(2) The seed potatoes must have been kept free from—

(i) potato viruses A, M, S, X, Y, leaf roll, potato mop top virus, tobacco rattle virus and tobacco veinal necrosis or any other significant virus;

(ii) witches’ broom and blackleg;

(iii) deviations of variety and type;

(iv) groundkeepers;

(v) plants of a different variety.

(3) The maximum number of field generations is four.