Plants & Pathways Directorate
TSB Bank Tower, 147 Lambton Quay
Wellington 6140, New Zealand
mpi.govt.nz
23 April 2020
Kia ora,
Subject: Consultation on the proposed changes to remove the Apiaceae schedule from Import Health 
Standard (IHS) 155.02.05: Seeds for Sowing
The Ministry for Primary Industries (MPI) invites feedback on proposed changes to import requirements in the 
IHS 155.02.05: Seeds for Sowing . You are being contacted as a stakeholder with a possible interest in the 
following matter and are invited to comment  on the proposed changes detailed below:
xRemoval of the Apiaceae schedule from the IHS 155.02.05: Seeds for Sowing .
Please note that the proposed changes will not prevent the importati on of Apiaceae seeds for sowing.
This letter includes the following information:
xThe MPI assessment for the proposed c hanges to import requirements (Appendix 1).
xThe MPI technical advice on “Review of evidence for seed transmission of liberibacter on carrot seed”
(Appendix 2).
xProposed changes to the IHS 155.02.05: Seeds for Sowing (Appendix 3).
MPI seeks comment on the proposed changes by close of business on Thursday, 28 May 2020. Any queries
and all submissions should be directed to PlantImports@mpi.govt.nz .
Yours sincerely,
Dr Sarah Clark
Manager Plant Germplasm Import team
Deputy Chief Technical Officer 
Plants & Pathways Directorate
Date2
Appendix 1
Assessment of proposed changes to re move the Apiaceae schedule from the IHS
155.02.05: Seeds for Sowing
Background
1. The Apiaceae schedule currently includes phytosanitary  measures to manage the risk of a bacterium 
‘Candidatus Liberibacter solanacearum’ (Lso) on the impo rt pathway of Apiaceae seeds for sowing 
(including carrot, celery, chervil, fennel, parsl ey and parsnip). The reasons for the current 
phytosanitary measures are outlined below.
2. Lso is a phloem-limited bacterium associated with  several vegetative diso rders in the Apiaceae,
Polygonaceae and Solanaceae families (Munyaneza et al. 2010; Haapalainen et al. 2020). The 
bacterium has been associated with damage to commer cial crops of these families, resulting in 
significant yield reduction and economic loss (Soukaina et al., 2019).
3. New Zealand produces vegetable seeds for domes tic use and export markets, notably radish and 
carrots. New Zealand supplies nearly 40% of the world production of carrot seed, with the export 
revenue over $30 million in 2018 (Fresh Facts, 2018). Since New Zealand is  one of the major 
producers of carrot seeds for global trade, Ls o could have adverse effects on New Zealand 
horticulture and vegetable seed industries, if in troduced through importation of infected seeds.
4. Lso isolates are currently characterised into nine haplotypes - A, B, C, D, E, F, G, H, and U 
(Haapalainen et al. 2020). Only haplotype A has been reco rded in New Zealand (causing zebra chip in 
potatoes). Haplotype B (recorded from Solanace ae), and haplotypes C, D, and E (recorded from 
Apiaceae) are regulated pests in New Zealand, meaning that they are consider ed to be able to cause 
unwanted harm in New Zealand.
5. Evidence in one scientific publication and from te sting of commercial seed led MPI to conclude in 2017 
that imported carrot seed was a risk pathway  for the introduction of Lso into NZ.
a) In 2015, it was reported that Lso was able to be transmitted from carrot seed to carrot 
seedlings (Bertolini et al., 2015),
b) In 2016, MPI detected Lso Haplotype D in a c onsignment of carrot seeds imported into New 
Zealand for re-exporting to Au stralia. Following this detection, MPI added a new schedule for 
Apiaceae seeds in the IHS: Seeds for Sowing , as an urgent amendment under the Biosecurity 
Act s24B(2), in June 2017. This amendment was considered as a provisional measure1.
Several consignments of carrot seeds contam inated with haplotype D have been intercepted 
at the border from 2017 to 2020.
6. The Apiaceae schedule requires that all imported seed lots must be accompanied by a phytosanitary 
certificate with an additional dec laration for Lso haplotypes C, D and E. The additional declaration 
must state that:
a) the seeds have been sourced from a country free from Lso haplotyp es C, D and E; or 
1 A provisional measure is defined in the International Standard s for Phytosanitary Measures (ISPM) 5 as ‘ A 
phytosanitary regulation or procedure established without full technical justification ow ing to current lack of 
adequate information. A provisional measure is subjected to per iodic review and full technica l justification as soon as 
possible .’ 3
5 March 2020b) a representative sample of 10,000 seeds has been sampled and tested for this bacteria 
(onshore or offshore) and found free; or 
c) the seed lot has been treated with hot water at 50°C for at least 30 continuous minutes. 
7. This provisional measure was subject to review and full technical assessment within a reasonable 
period, as per Article 5. 7 of the WTO-SPS agreement2.
Discussion of new evidence
8. New scientific evidence does not support the findi ng that Lso is seed transmitted on the Apiaceae
family (MPI Technical Advice, 2020, Appendix 2). A s a result, MPI no longer considers Apiaceae seed 
to be a risk pathway for introduction of Lso. This conclusion has been made based on the following:
a) The finding of Bertolini et al. (2015), indicating transmission of Lso haplotype E from seed to 
seedling in carrot, was not able to be repeated by further scientific studies:
i. The seed transmission of Lso haplotypes D and E in carrot was not confirmed using 
the same seed lots as Bertolini et al . (2015) (Loiseau et al. (2017a). The authors 
suggested that the discrepancy in result s could be due to differing agronomic 
conditions.
ii. Loiseau et al., (2017b) confir med the results obtained in t heir first experiment despite 
using the growing conditions similar to those described by Bertolini et al (2015). 
iii. Lso was not detected in the carrot crops gr own from seed lots that were known to be 
infected with Lso haplotype D (Haapalainen et al ., 2018). This result is consistent with 
the results of studies by Loiseau et al  (2017a, 2017b) which found no evidence for 
seed-to-seedling transmission of Lso by carrot seeds.
b) Research indicates that Lso is vector-transmitted3rather than seed-transmitted.
i. Detection of Lso only from seed coats (Ber tolini et al., 2015) provides evidence that 
Lso is transmitted by its known vector, psy llids. When psyllids feed on mature seeds, 
they introduce Lso to phloem tissue of seed coat (MPI Pest Risk Assessment, 2105; 
Monger and Jeffries, 2016). Seed transmitted pathogens should be detected from the 
embryo of seeds (Singh and Mathur, 2004).
Conclusion
1. MPI proposes to remove the Apia ceae schedule from the IHS, because:
a) there is insufficient evidence that  seed to seedling transmission of ‘ Candidatus Liberibacter 
solanacearum’ occurs in species of Apiaceae; and
2 Article 5.7 of the World Trade Organisation - Sanitary and phy tosanitary (WTO-SPS) agreement states ‘ In cases 
where relevant scientific evidence is insufficient, a Member ma y provisionally adopt sanitary or phytosanitary 
measures on the basis of available pertinent information, inclu ding that from the relevant international 
organizations as well as from s anitary or phytosanitary measure s applied by other Members. In such circumstances, 
Members shall seek to obtain the additional information necessa ry for a more objective assessment of risk and 
review the sanitary or phytosanitary measure accordingly within  a reasonable period of time ’. 
3 Lso is known to be tran smitted by psyllids. 4
b) the additional measures for the importation of  Apiaceae family introduced in June 2017 is no
longer technically justified.
2. Following the removal of Apiaceae schedule from t he Seeds for Sowing IHS, the import specification 
of all Apiaceae seeds for sowing species listed in t he Plant Biosecurity Index (PBI) will be altered to 
“Basic”.
3. MPI will continue to monitor research fi ndings related to seed transmission of Lso.
References
Bertolini, E; Teresani, G R; Loiseau, M; Tanaka, F A O; Barbe, S; Martinez, C; Gentit, P; Lopez, M M; 
Cambra, M (2015). Transmission of 'Candidatus Liberibacter solanacearum' in carrot seeds. Plant 
Pathology 64(2): 276-285. DOI: 10.1111/ppa.12245
Fact Sheets (2018). Page 21. Retrieved from https://www.freshfacts.co.nz/files/freshfacts-2018.pdf
Haapalainen, M., Latvala, S., Wickström, A. et al. (2020). A novel haplotype of ‘ Candidatus Liberibacter 
solanacearum’ found in Apiaceae a nd Polygonaceae family plants. European Journal of Plant 
Pathology 156, 413–423. https://doi.org/10.1007/s10658-019-01890-0
Haapalainen, M., Wang, J., Latva la, S., Lehtonen, M. T., Pirhonen, M. , Nissinen, A. I. (2018). Genetic 
variation of 'Candidatus Liberibacter solanacearum' haplotype C and  identification of a novel haplotype 
from Trioza urticae and stinging nettle. Phytopathology 108(8): 925-934.
IHS 155.02.05: Seeds for Sowing. Available at: https://www.biosecurity.govt.nz/dmsdocument/1151-
seeds-for-sowing-import-health-standard (Accessed: 23/03/2020).
International Standards for Phytosanitary Measur es (ISPM) 5. Glossary of  phytosanitary terms.
http://www.fao.org/fileadmin/user_upl oad/faoterm/PDF /ISPM_05_2016_En_2017-05-
25_PostCPM12_InkAm.pdf (Accessed: 23/03/2020).
Loiseau, M., Renaudin, I., Cousseau-Su hard, P., Lucas, P. M., Forveille,  A., Gentit, P. (2017a). Lack of 
evidence of vertical transmission of 'Candidatus Liberibacter solanacearum' by carrot seeds suggests that 
seed is not a major transmission pathway. Plant Disease 101(12): 2104-2109.
Loiseau, M., Renaudin, I., Cousseau-S uhard, P., Poliakoff, F., Gentit, P. (2017b). Transmission tests of 
'Candidatus Liberibacter solanacearum' by carrot seeds. Acta Horticulturae (1153): 41-46.
Monger, W. A., Jeffries, C. J.  (2016). First report of ' Candidatus Liberibacter solanacearum' in parsley 
(Petroselinum crispum ) seed. New Disease Reports 34, 31. http://dx.doi.org/10.5197/j.2044-
0588.2016.034.031
MPI Pest Risk Assessment (2105). 2015 Pest Risk Assessment: ‘ Candidatus Liberibacter solanacearum’ 
associated with imported carrot seeds for sowing. ISBN: 978-1-77665-162-7 (online) .
MPI Technical Advice (2020). Review of evidence fo r seed transmission of liberibacter on carrot seed.
February 2020 (see Appendix 2).5
5 March 2020Munyaneza, J. E., Fisher, T. W., Sengoda, V. G., Ga rczynski, S. F., Nissinen, A., Lemmetty, A. (2010).
First report of ‘ Candidatus Liberibacter solanacearum’ associated with psyllid-affected carrots in Europe. 
Plant Disease, 94(5):639. https://apsjournals.apsnet.org/loi/pdis
Singh, D. and Mathur, S. B. (2004). Histopathology of Seed-Borne Infections. Boca Raton, FL: CRC Press
Soukaina, B. O., Khaled Abbes, Mohamed El Imem, David Ouvrard,  Carmelo Rapisarda & Brahim 
Chermiti (2019). Bactericera trigonica andB. nigricornis (Hemiptera: Psylloidea) in  Tunisia as potential 
vectors of ‘ Candidatus Liberibacter solanacearum’ on Apia ceae, Oriental Insects, 53:4, 497-509,
DOI: 10.1080/00305316.2018.1536003
World Trade Organisation - Sanitary and phytosanita ry (WTO-SPS). Article 5: Assessment of Risk and 
Determination of the Appropriate Level of  Sanitary or Phytosanitary Protection.
https://www.wto.org/english /tratop_e/sps_e/spsagr_e.htm (Accessed: 23/03/2020).6
Appendix 2
Technical advice on: Review of evidence for seed transmi ssion of liberibacter on carrot seed.
Date:  28 February 2020
Purpose of document
The Plant Germplasm Imports team has request ed that the evidence for seed transmission of ‘ Candidatus
Liberibacter solanacearum’ for ca rrot and other Apiaceae be reviewed.
Background
‘Candidatus Liberibacter solanacearum’ (Lso) is an uncultur able bacterium that lives in  the phloem of its plant 
hosts causing disease on plants in the families Sol anaceae and Umbelliferae. It is vectored by psylloids4which 
feed on the phloem contents.
Several haplotypes (A, B, C, D, and E and others) have been recognised within  Lso. Haplotype A (Lso A) is 
present in New Zealand in Solanaceae (Liefting et al, 2009). New Zealand is free of all other known Lso 
haplotypes, including those that affect Apiaceae (e.g., carrot, Daucus carota ( Munyaneza et al, 2010)), and 
these haplotypes are regulated (BORIC5).Bactericera cockerelli , the vector of Lso haplotypes on solanaceous 
species, is present in New Zealand. However, the r eported vectors for Lso C, D, E and others on Apiaceae, 
including Trioza apicalis and Bactericera trigonica , are not known to be present  in New Zealand (MPI, 2015; 
not listed in PPIN, 2020).
In 2015, a single publication (Bertolini et al, 2015) r eported seed transmission of Lso in carrot. A subsequent 
Pest Risk Assessment (MPI, 2015) concluded that if Ls o was seed transmitted in Apiaceae then it would be a 
risk to New Zealand; however, there was insufficient evi dence to that date that this pathway (seed to seedling 
transmission in Apiaceae) occurs. Uncertainty (unquantified) remained because the evidence for seed 
transmission had not been independently verified, with t he issue still under discussion and investigation by 
international researchers.
Since 2015 other studies on seed to seedling tr ansmission of Lso on carrot have been published. The 
evidence for seed to seedling transmission of Lso in Ap iaceae is re-evaluated here taking these publications 
into account.
Summary of advice
There is insufficient evidence that seed to seedling transmission of ‘ Candidatus Liberibacter 
solanacearum’ occurs in carrot or other species of Apiaceae.
A single publication has reported seed transmissi on of Lso in carrot (Bertolini et al, 2015).
However, this publication was insufficient on its own to  clearly demonstrate that  seed transmission occurs on 
this pathway for several reasons: it had not been indep endently verified; the PCR primers used to detect Lso 
in seed and leaf midrib tissue are capable of detecti ng a wide range of other bacteria; DNA sequences from 
the study are unavailable (e.g. thr ough GenBank) for analysis by other researchers; and transmission electron 
4  Psylloids are members of the supe rfamily Psylloidea. The superf amily contains several fam ilies including Psyllidae 
and Triozidae. Members of the Psyllidae (e.g., Diaphorina citri ) are known as psyllids and members of the Triozidae 
(e.g., Trioza erytreae) are known as triozids. 
5 https://www.mpi.govt.nz/news-a nd-resources/resources/registers -and-lists/biosecurity-o rganisms-register-for-
imported-commodities 7
5 March 2020microscopy cannot be used alone as a diagnostic tool  for liberibacter without diagnostic DNA sequence 
information.
Other more recently published studies  have investigated seed transmission of Lso in Apiaceae. However, 
neither of these was able to demonstrate seed transmi ssion of Lso in carrot. Loiseau et al (2017b) in an 
independent laboratory used the same th ree lots of seed as Bertolini et al (2015). The authors suggested the 
discrepancy could be due to differing agronomic conditions. An additional study was conducted by Loiseau et 
al (2017a) which confirmed the result s obtained in their first experiment des pite using the growing conditions 
described by Bertolini et al (2015). Ot her hypotheses may explain the result s obtained by Bertolini et al (2015).
Supporting information
Original report of seed transmission
The study by Bertolini et al (2015) suggested that Lso is transmitted by seed in carrot. The authors developed 
a real-time PCR protocol for the specific detection and quantification of Lso in carrot seeds. This was used to 
detect Lso in carrot seed lots including those collect ed from diseased mother plants. Lso was also detected 
post-germination in seedlings grown from PCR positive seed lots in an insect-proof PC2 glasshouse. It was 
detected as early as 30 days post-germination, but more  consistently after 90 da ys. Some of the positive 
samples were sequenced by the authors and determined to be Lso haplotype E based on the 16S and 50S 
rRNA genes. Electron microscopy was used to show the presence of BLOs (bacteri a-like organisms) in the 
phloem sieve tubes of the seed coat  the phloem of the carrot mid-rib seedlings grown from positive seed.
The MPI pest risk analysis (MPI 2015) considered the Be rtolini et al (2015) pub lication when reaching the 
conclusion that there was insufficient evidence that seed to seedling transmission occurs in Apiaceae. The 
following is taken from the pest risk analysis (MPI, 2015):
A recent study by Bertolini et al. (20146) suggests that Lso is transmitt ed by seed in carrot. However, 
this remains to be confirmed by an independent laborat ory or further studies. The real-time PCR assay 
used in this study can potentially amplify a wide range of other bacteria that may be present as 
environmental contamination. Po sitive samples were sequenced by  the authors and determined to be 
Lso haplotype E based on the 16S and 50S rRNA genes. However, the sequences were not deposited 
in GenBank (or a similar sequence database) which is a standard requirement of publishing, and as a 
result are not readily availabl e for analysis. Although electron micr oscopy showed the presence of 
BLOs (bacteria-like organisms) in the phloem sieve tubes of the seed coat and in the phloem of the 
carrot mid-rib seedlings grown from pos itive seed, this result is inconclusive as liberibacters cannot be 
diagnosed from morphology only. Seed transmission has not yet been clearly demonstrated for other 
liberibacter species (personal communication, Lia Li efting, October 2014; Hilf et al. 2013, Hilf 2011, 
van Vuuren et al. 2011).
Additional studies of seed transmission
Other more recently published studies have investigated seed transmission of  Lso in Apiaceae (Loiseau et al, 
2017a, b). However, neither of these was able to demonstrate seed transmission of Lso in carrot.
Loiseau et al (2017b) in an independent l aboratory used the same three lots of seed as Bertolini et al (2015). 
Their study in France was carried out in parallel with the Spanish laboratory (Bertolini et al, 2015) to show that 
seed transmission is reproducible. However, they were  unable to demonstrate the transmission of Lso by 
carrot seeds and their results were not consistent with  those of Bertolini et al (2015). The authors suggested 
6 Bertolini et al (2015) first be came available in 2014 as an el ectronic publication. 8
that one of the most probable hypot heses for the discrepancy could be due to  differing agronomic conditions. 
They had subjected their seedlings to an overwintering regime to produce seeds and this could have inhibited 
the development of the bacteria. The authors noted ther e are other possible hypotheses such as cross-
contamination.
An additional study was conducted by Loiseau et al (2017a) which confirmed the results obtained in their first 
experiment despite using the growing conditions equivalent  to those described by Bertolini et al (2015). These 
authors concluded: ‘If the transmission of ‘Ca. L. solanacearum’ by carrot seed is at all possible, it is probably 
rare and difficult to reproduce.’ In this study the plant s were grown for 6 months in an insect-proof greenhouse. 
Sets of plants from the contaminat ed lots and from the healthy lots we re individually analysed each month 
using real-time PCR to detect Lso. Tests on seeds and plants from healthy lots were  always negative. During 
the 6 months of the tria l, no plants from the contaminated seed lots  tested positive for Lso or showed any 
typical infection symptoms. 
During the course of the study, a small number of inc onclusive results from the PCR assays were obtained 
from the third month samples to the sixth month (Loiseau et al, 2017a). In these cases, the detection of the 
bacterium was repeated on those carrots that gave inconclu sive results. No positive results were obtained on 
the stored crude extracts or on new samples of the same plants. In addition, the pl ants that gave inconclusive 
results during any one sampling period were not found to give inconclusive results in any other sampling 
period. As a result, the nine inconclusive results obtai ned during the study were considered by the authors to 
be micro-contaminations during DNA extraction or amplification even though positive and negative controls in 
both steps were clear. 
This and the previous study (Loiseau et al 2017b) used t he real-time PCR primers developed by Li et al (2009) 
rather than those used in Bertolini et al (2015). Real-time  PCR primers used by Li et  al (2009) were found to 
be the most sensitive and robust of those tested in an eval uation by Ilardi et al (2019) of a diagnostic protocol 
for Lso in carrot seeds. The primers used by Teresani  et al (2014), which are the same as those used by 
Bertolini et al (2015), were included in their evaluation. 
In Japan, a comparison of protocols to detect Lso in carrot seeds was undertaken by Oishi et al (2017). Their 
study used real-time PCR to evaluate 1,438 seedlings  grown from five Lso positive seed lots and seed 
transmission of Lso was not observed. This finding s upports those of Loiseau et al  (2017a, b) but this paper 
has not been assessed thoroughly here as the full text was not in English.
The positive results obtained by Bertoli ni et al (2015) were most likely due to either cross-c ontamination during 
DNA extraction or PCR amplification and/or due to non-specific amplificati on of organisms closely related to 
liberibacters.
Additional observations
Haapalainen et al (2018) investigated the occurrence of Lso haplotypes in various psyllids and plant hosts in 
Finland. Samples included carrot seeds used for carro t production by commercial carrot growers. The 
commercial growers use imported carrot seeds since t here is no domestic carrot seed production in Finland. 
Plants (carrot, parsnip, and wild plants growing as w eeds in and next to carrot fields) and psyllids feeding on 
these plants were also sampled. At the time of the study, only Lso haploty pe C was known to occur in Finland. 
Lso haplotype D was confirmed in 2 of the 34 imported carrot seed lots tested. Plants grown in the field from 
the infected imported seed lots were tested at the end of  the season. Haplotype D was not detected in these 
plants nor had it been detected in any ot her plants or psyllids in Finland. Haapalainen et al ( 2018) stated that 
their results agreed with the Loiseau et al (2017a) study  which found no evidence for vertical transmission of 
Lso by carrot seeds. The authors also not ed the possibility that haplotype D or its vector might not  suit the cool 
conditions found in Finland. However, if it was able to survive and spread then it would be expected to be 
found in carrots in Finland because field-scale cultiv ation of carrots had occu rred there since the late 
nineteenth century. 9
5 March 2020Monger and Jeffries (2018) carried out a survey of seed of carrot and related Apiaceae species held in three 
seed collections in the United Kingdom. Accession s went back as far as the 1970s and the seed had been 
sourced worldwide. They found that a high proportion of  commercial carrot seed lots from European sources 
were infected with Lso dating back to 1973; 74% of European carrot from the 1970s and 63% from the 1980s 
and 90s were positive for Lso indicating that it has been present in European crops for many years and at high 
levels. Given the international trade in Apiaceae seed,  it is expected that Lso positive seed would have been 
exported worldwide. However, the incidence of Lso in the seeds in the study showed a clear distinction 
between the European-Mediterranean region and the rest of the world with few findings in seed from countries 
in the latter category. The authors conclude that Lso is not an emergi ng pathogen in European Apiaceae crops 
but rather has gone unnoticed and undetermined for a long ti me and reaches economic levels when vector 
populations increase under fav ourable environmental condi tions to cause epidemics.
In addition, there is no evidence that Lso is seed transmitted through true seed from infected solanaceous 
plants (potato, tomato, peppe r, tamarillo) (Munyaneza 2012; Lie fting, personal communication).
Nor is there sufficient evidence that other liberi bacter species are seed transmitted. In particular. ‘ Candidatus
Liberibacter asiaticus’, associated with huanglongbing disease of citrus, has been the subject of much 
research effort in this area. Older studies s uggesting seed transmission have not been supported by more 
recent more robust studies (e.g., Hartung et al, 2010; Hilf  et al. 2013, Hilf 2011). Alte rnative explanations such 
as PCR contamination or reliance on non-specific symptoms can explain results of earlier studies.
References:
Bertolini, E; Teresani, G R; Loiseau, M; Tanaka, F A O; Barbe, S; Martinez, C; G entit, P; Lopez, M M; Cambra, 
M (2015) Transmission of 'Candidatus Liberibacter solanacearum' in carrot seeds. Plant Pathology 64(2): 276-
285.
Haapalainen, M; Wang, J; Latvala, S; Lehtonen, M T; Pirhonen, M; Nissinen,  A I (2018) Genetic variation of 
'Candidatus Liberibacter solanacearum' h aplotype C and identificatio n of a novel haplotype from Trioza urticae
and stinging nettle. Phytopathology 108(8): 925-934.
Hartung, J S; Halbert, S E; Pelz-Steli nski, K; Brlansky, R H; Chen, C; Gm itter. F G (2010) Lack of evidence for 
transmission of 'Candidatus Liberibacter asiaticus' through ci trus seed taken from affected fruit. Plant Disease
94(10):1200–1205.
Hilf, M E (2011) Colonization  of citrus seed coats by ‘ Candidatus Liberibacter asiaticus’: Implications for seed 
transmission of the bacterium. Phytopathology 101: 1242–1250.
Hilf, M E; Sims, K R; Folimonova, S Y; Achor, D S (2013) Visualization of ‘ Candidatus Liberibacter asiaticus’ 
cells in the vascular bundle of citrus seed coats with  fluorescence in situ hybridization and transmission 
electron microscopy. Phytopathology 103: 545–554.
Ilardi, V; Lumia,V; Di Nicola, E; Ta vazza, M (2018) Identific ation, intra- and inter-laboratory validation of a 
diagnostic protocol for 'Candidatus Liberibacter solanacearum' in carrot seeds. European Journal of Plant 
Pathology 153: 879-890.
Li, W; Abad, J A; French-Monar, R D; Rascoe, J; Wen, A;  Gudmestad, N C; Secor, G A; Lee, I. M; Duan, Y; 
Levy, L (2009) Multiplex real-time PCR for det ection, identification and quantification of ‘ Candidatus
Liberibacter solanacearum’ in potato plants with zebra chip. Journal of Microbiological Methods 78(1): 59-65.
Liefting, L W; Sutherland, P W; Wa rd, I L; Paice, K L; Weir, B S; Clover, G R G (2009) A new ‘Candidatus 
Liberibacter’ species associated with diseases of solanaceous crops. Plant Disease 93(3): 208–214.10
Loiseau, M; Renaudin, I; Cousseau-Suhard, P; Lucas, P M;  Forveille, A; Gentit, P (2017a) Lack of evidence of 
vertical transmission of 'Candidatus Liberibacter solanacearum' by carrot seeds suggests that seed is not a 
major transmission pathway. Plant Disease 101(12): 2104-2109.
Loiseau, M; Renaudin, I; Cousseau-Suhard, P; Polia koff, F; Gentit, P (2017b)  Transmission tests of 
'Candidatus Liberibacter solanacearum' by carrot seeds. Acta Horticulturae (1153): 41-46.
MPI (2015) Pest Risk Assessment: ‘ Candidatus Liberibacter solanacearum’ associated with imported carrot 
seeds for sowing. Ministry for Prim ary Industries, New Zealand. (28 pp.)
Monger, W A; Jeffries, C J (2018) A survey of 'Candidatus Liberibacter solanacearum' in historical seed from 
collections of carrot and related Apiaceae species. European Journal of Plant Pathology 150(3): 803-815.
Munyaneza, J E; Fisher, T W; Sengoda,  V G; Garczynski, S F; Nissinen, A;  Lemmetty, A (2010) First report of 
“Candidatus Liberibacter solanacearum” associated with  psyllid-affected carrots in Europe. Plant Disease
94(5): 639.
Munyaneza, J E (2012) Zebra chip disease of  potato: biology, epidemiology, and management. American 
Journal of Potato Research 89: 329–350.
Oishi, M; Hoshino, S; Fujiwara, Y; Ushiku, S; Kobayas hi, Y; Namba, I (2017)  A comparison of protocols to 
detect Candidatus Liberibacter solanacearum from carrot seeds, research on the effectiveness of propidium 
monoazide treatment and ev aluation of seed transmission in carrot seeds. Res. Bull. Pl. Prot. Japan 53:111-
117.
PPIN (2020) Plant Pest Information Network Database. Ministry for Pr imary Industries. [Accessed February 
2020].
Teresani, G R; Bertolini, E; Alfaro-Fernández, A; Mar tínez, C; Tanaka, F A O; Kitajima, E W; Roselló, M; 
Sanjuán, S; Ferrándiz, J C; López, M M; Cambra, M; Font, M I (2014) Association of ‘ Candidatus Liberibacter 
solanacearum’ with a vegetative disorder of celery in Spain and development of a r eal-time PCR method for its 
detection. Phytopathology 104: 804-811.
van Vuuren S P; Cook G; Pietersen G (2011)  Lack of evidence for seed transmission of ‘ Candidatus
Liberibacter africanus’ associated with greening (huanglongbing) in citrus in South Africa. Plant Disease 95(8): 
1026.
 
 11
5 March 2020Appendix 3
It is proposed to remove Apiac eae schedule from the IHS 155.02.05: Seeds for Sowing
2.7 Apiaceae
The following requirements only apply to species in the Plant Biosecurity Index listed under Import Specifications for 
Seed as “see 155.02.05 under Apiaceae” . 
Approved countries : All 
Quarantine pests : ‘Candidatus Liberibacter solanacearum’ haplotypes C, D and E
Import permit : Not required 
PEQ : Not required
Phytosanitary certificate: Required
Approved treatment
If the treatment option is selected:
(1) Each seed lot must be treated using a hot wate r dip, for the treatment of bacterial organisms (‘ Candidatus 
Liberibacter solanacearum ’haplotypes C, D and E) as per MPI Standard MPI-STD-ABTRT Approved Biosecurity 
Treatments . 
(2) The hot water treatment is required  to be completed offshore prior to export, or on arrival in New Zealand. 
(3) Pre-export treatment for each seed  lot must be endorsed by the NPPO  in the treatment section on the 
phytosanitary certificate, where the temp erature and time must be clearly stated.
Phytosanitary certificate – Additional declarations 
(4) The required additional declarations must be endorsed in full on the phytosanitary certificate, no variations in the 
wording will be accepted by MPI, with exception of translation artifacts. 
(5) The exporting country NPPO must co nfirm any treatment(s) as required by the IHS in the disinfestation and/or 
disinfection treatment section.
(6) If satisfied that the pre-shipment ac tivities have been undertaken, the exporting country NPPO must confirm this 
by providing the certifying statement as per Part 1.5.2 of this import health standard and also the following 
additional declaration (s) to the phytosanitary certificate:
a) ‘ Candidatus Liberibacter solanacearum’ haplotypes C, D,  and E are absent/not known to occur in 
____________ (name of country).
OR
b) the seeds for sowing have been sourced from a se ed lot officially sampled according to ISTA or 
AOSA methodology, and tested using a NPPO approved PCR method and found free from 
Candidatus Liberibacter solanacearum  haplotypes C, D and E.
OR
c) the seeds for sowing have been tr eated with hot water at a minimum temperature of 50ºC for at least 
20 continuous minutes.12
Testing Requirements
If the testing option is selected:
(7) Testing is required to  be completed offshore prior to export, or on arrival in New Zealand. 
(8) Pre-export testing for each seed lot must be endorsed by the NPPO on the phytosanitary certificate, or if tested 
on arrival in New Zealand, must be complete d by an MPI-approved testing laboratory. 
(9) A representative sample of a minimu m of 10,000 seeds, is required from ea ch seed lot and tested using the real-
time PCR assay described by Li et al., 2009 to show the cons ignment is free of ‘ Candidatus Liberibacter 
solanacearum’ haplotypes C, D and E.
Guidance: 
Refer section 1.11 Seeds of MPI Standard MPI-STD-ATBRT Approved Biosecurity Treatments
References: 
Li, W., Abad, J. A., French-Monar, R. D ., Rascoe, J., Wen, A., Gudmestad, N. C ., Secor, G. A., Lee, I. M., Duan, Y., 
and Levy, L. 2009. Multiplex real-time PCR for dete ction, identification and quantification of ‘ Candidatus
Liberibacter solanacearum’ in potato plants with zebra chip. Journal of Microbiological Methods 78:59-65.