{
  "url": "https://openlegislation.uk/seed-potatoes-regulations-northern-ireland-2016/schedule-4/paragraph-1",
  "json_url": "https://openlegislation.uk/seed-potatoes-regulations-northern-ireland-2016/schedule-4/paragraph-1.json",
  "legislation": "nisr/2016/190",
  "legislation_title": "The Seed Potatoes Regulations (Northern Ireland) 2016",
  "legislation_url": "https://openlegislation.uk/seed-potatoes-regulations-northern-ireland-2016",
  "path": "schedule/4/paragraph/1",
  "kind": "paragraph",
  "number": "1",
  "heading": null,
  "text": "In this Schedule—\n(a) Table 1 sets out the applicable requirements as regards source material, other requirements and tolerances in respect of the grading of pre-basic seed potatoes as UK grade PBTC or UK grade PB; and\n(b) Table 2 sets out the applicable requirements as regards source material, other requirements and tolerances in respect of the grading of basic seed potatoes as UK grade S, UK grade SE or UK grade E.\nTable 1\nUK grades for pre-basic seed potatoes\nColumn 1 UK grade\nColumn 2Source material\nColumn 3Other requirements\nColumn 4Tolerances\nPBTC\nThe seed potatoes shall be derived from nuclear stock or mother plants that are free from Blackleg, Dickeya, Leafroll, PVA, PVY and Potato viruses M, S and X\nThe seed potatoes shall be—\n(a) grown in a facility officially approved for the production of seed potatoes of UK grade PBTC;\n(b) produced through micro-propagation;\n(c) kept free, as far as is practicable from diseases and aphids by appropriate husbandry measures; and\n(d) the first generation of this stock\nA sample of the seed potatoes taken during an official examination shall not exceed the following tolerances—\n(a) conditions concerning seed potato crops:\n(i) deviations from variety – NIL;\n(ii) mosaic symptoms – NIL;\n(iii) Leafroll symptoms – NIL;\n(iv) Blackleg – NIL;\n(v) in the direct progeny virus infection shall not be present in the crop.\n(b) lots of seed potatoes shall be free from:\n(i) Rots (including Blight, Gangrene, Dry Rot and wet rot);\n(ii) Black Scurf;\n(iii) Common Scab;\n(iv) Powdery Scab;\n(v) Skin Spot;\n(vi) having become excessively shrivelled due to dehydration;\n(vii) external blemishes including misshapen or damaged tubers.\n(c) the presence of earth and extraneous matter in lots of seed potatoes shall not exceed 1% by mass.\nPB\nThe seed potatoes shall derive from nuclear stock or mother plants that are free from Blackleg, Dickeya, Leafroll, PVA, PVY and Potato viruses M, S and X, up to a maximum of 3 field generations.\nA sample of the seed potatoes taken during an official examination shall not exceed the following tolerances—\n(a) conditions concerning seed potato crops:\n(i) deviations from variety and type – 0.01%;\n(ii) symptoms caused by mosaic, other than PVA and PVY – 0.1%;\n(iii) symptoms caused by PVA, PVY and Leafroll – NIL;\n(iv) Blackleg – NIL;\n(v) in the direct progeny the number of plants with symptoms caused by any virus shall not exceed 0.5%.\n(b) tolerances applicable to lots of seed potatoes, as regards the following impurities, blemishes and diseases:\n(i) seed potatoes affected by Rots (other than Ring Rot or Brown Rot) shall not exceed 0.2% by mass;\n(ii) seed potatoes affected by Black Scurf over more than 10% of their surface shall not exceed 1% by mass;\n(iii) seed potatoes affected by Common Scab over more than one third of their surface shall not exceed 5% by mass;\n(iv) seed potatoes affected by Powdery Scab over more than 10% of their surface shall not exceed 1% by mass;\n(v) seed potatoes affected by Skin Spot shall not exceed 0.2% by mass;\n(vi) shrivelled tubers due to excessive dehydration or dehydration caused by Silver Scurf, shall not exceed 0.5% by mass;\n(vii) seed potatoes with external blemishes including misshapen or damaged tubers shall not exceed 3% by mass;\n(viii) the presence of earth and extraneous matter shall not exceed 1% by mass; and\n(ix) the total percentage of seed potatoes covered by tolerances, as referred to in points (i) to (vii) shall not exceed 6% by mass\nTable 2\nUK grades for basic seed potatoes\nColumn 1UK grade\nColumn 2Source material\nColumn 3Tolerances\nS\nThe seed potatoes shall be derived from stock—\n(a) where the grade is recorded either on a growing crop report or on an official label or official document as UK grade PBTC or Union grade PBTC or Union grade PB in the year preceding the planting of the crop;\n(b) where the grade is recorded either on a growing crop report or on an official label or official document as UK grade S or Union grade S, up to a maximum of 4 generations (including pre-basic in the field and basic generations), in the year preceding the planting of the crop; or\n(c) such other seed potatoes as are notified in writing by the Department as being acceptable to the Department\nA sample of the seed potatoes taken during an official examination shall not exceed the following tolerances—\n(a) conditions concerning seed potato crops:\n(i) deviations from variety and type – 0.1%;\n(ii) symptoms caused by PVA, PVY and Leafroll – 0.02%;\n(iii) total percentage of symptoms caused by mosaic (including PVA and PVY) and Leafroll – 0.2%;\n(iv) Blackleg – 0.1%;\n(v) in the direct progeny the number of plants with symptoms of virus infection shall not exceed 1%.\n(b) tolerances applicable to lots of seed potatoes, as regards the following impurities, blemishes and diseases:\n(i) seed potatoes affected by Rots (other than Ring Rot or Brown Rot) shall not exceed 0.5% by mass, of which wet rot shall not exceed 0.2%;\n(ii) seed potatoes affected by Black Scurf over more than 10% of their surface shall not exceed 5% by mass;\n(iii) seed potatoes affected by Common Scab over more than one third of their surface shall not exceed 5% by mass;\n(iv) seed potatoes affected by Powdery Scab over more than 10% of their surface shall not exceed 3% by mass;\n(v) seed potatoes affected by Skin Spot over more than 12.5% of their surface shall not exceed 2% by mass;\n(vi) shrivelled tubers due to excessive dehydration or dehydration caused by silver scurf, shall not exceed 1% by mass;\n(vii) seed potatoes with external blemishes including misshapen or damaged tubers shall not exceed 3% by mass;\n(viii) the presence of earth and extraneous matter shall not exceed 1% by mass; and\n(ix) the total percentage of seed potatoes covered by tolerances, as referred to in points (i) to (vii) shall not exceed 6% by mass.\nSE\nThe seed potatoes shall be derived from stock—\n(a) where the grade is recorded either on a growing crop report or on an official label or official document as UK grade PBTC or Union grade PBTC or Union grade PB in the year preceding the planting of the crop;\n(b) where the grade is recorded either on a growing crop report or on an official label or official document as UK grade S or Union grade S or Union grade SE, up to a maximum of 5 generations (including pre-basic in the field and basic generations), in the year preceding the planting of the crop; or\n(c) such other seed potatoes as are notified in writing by the Department as being acceptable to the Department.\nA sample of the seed potatoes taken during an official examination shall not exceed the following tolerances—\n(a) conditions concerning seed potato crops:\n(i) deviations from variety and type – 0.1%;\n(ii) symptoms caused by PVA, PVY and Leafroll – 0.1%;\n(iii) total percentage of symptoms caused by mosaic (including PVA and PVY) and Leafroll – 0.5%;\n(iv) Blackleg – 0.5%;\n(v) in the direct progeny the number of plants with symptoms of virus infection shall not exceed 2%.\n(b) tolerances applicable to lots of seed potatoes, as regards the following impurities, blemishes and diseases:\n(i) seed potatoes affected by Rots (other than Ring Rot or Brown Rot) shall not exceed 0.5% by mass, of which wet rot shall not exceed 0.2%;\n(ii) seed potatoes affected by Black Scurf over more than 10% of their surface shall not exceed 5% by mass;\n(iii) seed potatoes affected by Common Scab over more than one third of their surface shall not exceed 5% by mass;\n(iv) seed potatoes affected by Powdery Scab over more than 10% of their surface shall not exceed 3% by mass;\n(v) seed potatoes affected by Skin Spot over more than 12.5% of their surface shall not exceed 2% by mass;\n(vi) shrivelled tubers due to excessive dehydration or dehydration caused by Silver Scurf, shall not exceed 1% by mass;\n(vii) seed potatoes with external blemishes including misshapen or damaged tubers shall not exceed 3% by mass.\n(viii) the presence of earth and extraneous matter shall not exceed 1% by mass; and\n(ix) the total percentage of seed potatoes covered by tolerances, as referred to in points (i) to (vii) shall not exceed 6% by mass.\nE\nThe seed potatoes shall be derived from stock—\n(a) where the grade is recorded either on a growing crop report or on an official label or official document as UK grade PBTC or Union grade PBTC or Union grade PB in the year preceding the planting of the crop;\n(b) where the grade is recorded either on a growing crop report or on an official label or official document as UK grade S, UK grade SE or Union grade S or Union grade SE, up to a maximum of 6 generations (including pre-basic in the field and basic generations), in the year preceding the planting of the crop; or\n(c) such other seed potatoes as are notified in writing by the Department as being acceptable to the Department.\nA sample of the seed potatoes taken during an official examination shall not exceed the following tolerances—\n(a) conditions concerning seed potato crops:\n(i) deviations from variety and type – 0.1%;\n(ii) symptoms caused by PVA, PVY and Leafroll – 0.4%;\n(iii) total percentage of symptoms caused by mosaic (including PVA and PVY) and Leafroll – 0.8%;\n(iv) Blackleg – 1%;\n(v) in the direct progeny the number of plants with symptoms of virus infection shall not exceed 4%;\n(b) tolerances applicable to lots of seed potatoes, as regards the following impurities, blemishes and diseases:\n(i) seed potatoes affected by Rots (other than Ring Rot or Brown Rot) shall not exceed 0.5% by mass, of which wet rot shall not exceed 0.2%;\n(ii) seed potatoes affected by Black Scurf over more than 10% of their surface shall not exceed 5% by mass;\n(iii) seed potatoes affected by Common Scab over more than one third of their surface shall not exceed 5% by mass;\n(iv) seed potatoes affected by Powdery Scab over more than 10% of their surface shall not exceed 3% by mass;\n(v) seed potatoes affected by Skin Spot over more than 12.5% of their surface shall not exceed 2% by mass;\n(vi) shrivelled tubers due to excessive dehydration or dehydration caused by Silver Scurf, shall not exceed 1% by mass;\n(vii) seed potatoes with external blemishes including misshapen or damaged tubers shall not exceed 3% by mass;\n(viii) the presence of earth and extraneous matter shall not exceed 1% by mass; and\n(ix) the total percentage of seed potatoes covered by tolerances, as referred to in points (i) to (vii) shall not exceed 6% by mass.",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "F",
      "label": "F1",
      "text": "Word in Sch. 4 para. 1 substituted (31.12.2020) by The Animal Health, Seed Potatoes and Food (Amendment) (Northern Ireland) (EU Exit) Regulations 2019 (S.I. 2019/962), regs. 1(2), 23(b); 2020 c. 1, Sch. 5 para. 1(1)"
    },
    {
      "type": "F",
      "label": "F2",
      "text": "Word in Sch. 4 Table 1 heading substituted (31.12.2020) by The Animal Health, Seed Potatoes and Food (Amendment) (Northern Ireland) (EU Exit) Regulations 2019 (S.I. 2019/962), regs. 1(2), 23(c)(i); 2020 c. 1, Sch. 5 para. 1(1)"
    },
    {
      "type": "F",
      "label": "F3",
      "text": "Word in Sch. 4 Table 1 substituted (31.12.2020) by The Animal Health, Seed Potatoes and Food (Amendment) (Northern Ireland) (EU Exit) Regulations 2019 (S.I. 2019/962), regs. 1(2), 23(c)(ii); 2020 c. 1, Sch. 5 para. 1(1)"
    },
    {
      "type": "F",
      "label": "F4",
      "text": "Word in Sch. 4 Table 2 heading substituted (31.12.2020) by The Animal Health, Seed Potatoes and Food (Amendment) (Northern Ireland) (EU Exit) Regulations 2019 (S.I. 2019/962), regs. 1(2), 23(d)(i); 2020 c. 1, Sch. 5 para. 1(1)"
    },
    {
      "type": "F",
      "label": "F5",
      "text": "Word in Sch. 4 Table 2 substituted (31.12.2020) by The Animal Health, Seed Potatoes and Food (Amendment) (Northern Ireland) (EU Exit) Regulations 2019 (S.I. 2019/962), regs. 1(2), 23(d)(ii); 2020 c. 1, Sch. 5 para. 1(1)"
    },
    {
      "type": "F",
      "label": "F6",
      "text": "Words in Sch. 4 Table 2 inserted (31.12.2020) by The Animal Health, Seed Potatoes and Food (Amendment) (Northern Ireland) (EU Exit) Regulations 2019 (S.I. 2019/962), regs. 1(2), 23(d)(iii)(aa); 2020 c. 1, Sch. 5 para. 1(1)"
    },
    {
      "type": "F",
      "label": "F7",
      "text": "Words in Sch. 4 Table 2 inserted (31.12.2020) by The Animal Health, Seed Potatoes and Food (Amendment) (Northern Ireland) (EU Exit) Regulations 2019 (S.I. 2019/962), regs. 1(2), 23(d)(iii)(bb); 2020 c. 1, Sch. 5 para. 1(1)"
    },
    {
      "type": "F",
      "label": "F8",
      "text": "Words in Sch. 4 Table 2 inserted (31.12.2020) by The Animal Health, Seed Potatoes and Food (Amendment) (Northern Ireland) (EU Exit) Regulations 2019 (S.I. 2019/962), regs. 1(2), 23(d)(iv)(aa); 2020 c. 1, Sch. 5 para. 1(1)"
    },
    {
      "type": "F",
      "label": "F9",
      "text": "Words in Sch. 4 Table 2 inserted (31.12.2020) by The Animal Health, Seed Potatoes and Food (Amendment) (Northern Ireland) (EU Exit) Regulations 2019 (S.I. 2019/962), regs. 1(2), 23(d)(iv)(bb); 2020 c. 1, Sch. 5 para. 1(1)"
    },
    {
      "type": "F",
      "label": "F10",
      "text": "Words in Sch. 4 Table 2 inserted (31.12.2020) by The Animal Health, Seed Potatoes and Food (Amendment) (Northern Ireland) (EU Exit) Regulations 2019 (S.I. 2019/962), regs. 1(2), 23(d)(v)(aa); 2020 c. 1, Sch. 5 para. 1(1)"
    },
    {
      "type": "F",
      "label": "F11",
      "text": "Words in Sch. 4 Table 2 inserted (31.12.2020) by The Animal Health, Seed Potatoes and Food (Amendment) (Northern Ireland) (EU Exit) Regulations 2019 (S.I. 2019/962), regs. 1(2), 23(d)(v)(bb); 2020 c. 1, Sch. 5 para. 1(1)"
    }
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  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/nisr/2016/190/schedule/4/paragraph/1",
    "retrieved_at": "2026-10-29T00:56:47.729828+00:00"
  },
  "licence": "Open Government Licence v3.0",
  "licence_url": "https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
  "attribution": "Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives."
}