Risk Management Proposal:   
Malus  spp. Seed for Sowing  
from all countries  
 
FOR PUBLIC CONSULTATION 
 
   
 
 
  2 November  2012  
                                        
Plant Imports  
Plant s, Food & Environment  
Ministry for Primary Industries  
Pastoral House  
25 The Terrace 
PO Box 2526  
Wellington 6140  
New Zealand  
 
Tel: +64 4 894 0100 
Fax: +64 4 894 0662 
 
Email: plantimports@mpi.govt.nz   
i  
 
Contents  Page 
 
Purpose  1 
Background  1 
Commodity description  1 
Source information  1 
International setting  2 
Objective  2 
Summary of Risk  2 
Risk Management  3 
PRE-EXPORT PHYTOSANITARY INSPECTION AND CERTIFICATION  4 
ON ARRIVAL VERIFICATION OF PRE -EXPORT MEASURES  4 
POST ENTRY QUARANTINE (peq)  5 
GROWING SEASON INSPECTION  5 
TESTING FOR REGULATED ORGANISMS OF SIGNIFICANT BIOSECURITY CONCERN 5 
NON- COMPLIANCE  5 
EQUIVALENCE  5 
BIOSECURIT Y CLEARANCE 5 
Proposed IHS requirements  6 
TOMATO BUSHY STUNT VIRUS  6 
APPLE SCAR SKIN VIROID  6 
POST ENTRY QUARANTINE 7 
REFERENCES  8 
  
Ministry for Primary Industries   {Malus  spp. seed for sowing from all countries RMP for public consultation} • 1  
Purpose  
1. The purpose of this document is to:  
a) Summarise the known biosecurity risks  associated with Malus  spp. (apple) seed for 
sowing from all countries  
b) Summarise how the proposed measures can effectively manage these risks  
c) Establish the feasibility, practicality of implementation of the proposed measures  
d) Seek stakeholder feedback on the proposed phytosanitary measures  
 
This import health standard (IHS) schedule has been amended  in accordance wit h 
Sections 23 and 24 of the Biosecurity Act 1993. 
 
Background  
2. The Malus  seed schedule in the import health standard 155.02.05: Importation of Seed 
for Sowing was previously issued on 24 November 2003. A review of the import 
requirements for imported  nurser y stock was completed in June 2012, based on the draft 
MPI risk analysis for apple nursery stock (2009) . The Malus  seed for sowing schedule 
has been reviewed to bring it into alignment with the nursery stock schedule .  
 
COMMODITY DESCRIPTION  
3. The IHS will c over all approved species of apple seed for sowing as listed on the MPI 
Plants Biosecurity Index , which are imported into New Zealand for the purpose of 
propagation. Under the current and proposed reviewed IHS, apple seeds are not eligible 
for biosecurity clearance on arrival in New Zealand. Seeds are imported into a MPI -
approved Post Entry Quarantine (PEQ) facility, where they are germinated and the resulting daughter plants grown. Only daughter plants are eligible for biosecurity clearance.  
 
SOURCE INFORMATION 
4. In the development of the risk management proposal the following information was used 
to identify risk organisms and the appropriate measures to manage their entry and establishme nt in New Zealand:  
a) The seed for sowing IHS schedule for Malus under the IHS   155.02.05: 
Importation of Seed for  Sowing  
b) The proposed draft nursery stock IHS schedule for  Malus  under the I HS                                             
http://www.biosecurity.govt.nz/files/biosec/consult/draft -ihs-schedule -malus.pdf  
c) The MPI  Post-Entry Quarantine Testing Manual for Malus (Apple)  
d) The MPI  risk analysis of the viruses, viroids, phytoplasma, bacteria and diseases of 
unknown aetiology on Malus  nursery stock from all countries  
http://www.biosecurity.govt.nz/files/regs/imports/risk/draft- ira-apple -nursery -
stock.pdf   
 Ministry for Primary Industries                                           {Malus  spp. seed for sowing from all countries RMP for public consultation}  • 2 INTERNATIONAL SETTING  
5. Where possible, phytosanitary measures are aligned with international standards, 
guidelines, and recommendations as per New Zealand’s obligations under Article 3.1 of the WTO Agreement on the Application of Sanitary and Phytosanitary Measures (SPS Agreement), WTO 1995.  
 
6. The SPS Agreem ent states that phytosanitary measures must not discriminate unfairly 
between countries or between imported or domestically produced goods, and where there is a choice of phytosanitary measures to reduce risk to an acceptable level, WTO members must select  the least trade restrictive measure.  
 
Objective  
7. MPI’s objective is to ensure the known biosecurity risks associated with apple seed for sowing are managed appropriately and are consistent with New Zealand’s domestic legislation and international obligations.  
 
Summary of Risk  
8. The Malus  seed for sowing  schedule currently identifies  four quarantine organisms which 
are regulated  on seeds for sowing. The draft pest risk analysis for Malus  nursery stock 
provided evidence that tw o of these organisms are no t associated with apple seed for 
sowing , and need to be removed from the quarantine pest list. They are:  
a) The fungus Monilinia frutigena, and 
b) Sowbane mosaic virus . 
 
9. The quarantine organisms Tomato bushy stunt virus  and Apple scar skin viroid are still 
viewed as  a risk associated with imported apple seed, and MPI  will continue to require 
measures in place for these. The proposed management steps for these regulated organisms are discussed in the Risk Management section of this document. The 
MPI 
PHEL testing manual for Malus  (Appendix 1 of manual) provides photos of symptoms 
caused by some of the organisms listed above.  
 
10. Risk organisms a re regulated on  seeds for sowing if they :  
a) are not known to occur in New Zealand, and  
b) are likely to be present on the pathway if risk was unmitigated, and  
c) are known to be associated with the commodity, and  
d) have host species which are present in New Zealand, and  
e) are c limatically able to establish in New Zealand, and  
f) are likely to cause high economic impact to New Zealand.  
 
11. Tomato Bushy Stunt Virus  
The regulated status of  Tomato bushy stunt virus (TBSV)  is retained as a result of the 
current review.  TBSV  is not known to be present in New Zealand, and if  identified in 
PEQ , MPI will take action on it.  
 
12. Seed is reported to be a factor in the  spread of TBSV (Kegler and Schimanski 1982), 
along with mechanical inoculation, grafting, and possibly  also pollen (Kegler and Kegl er 
1980). TBSV can also be released from the roots of infected plants into the soil where is can remain infective for up to 12 weeks (Kegler et al. 1983).  
   
Ministry for Primary Industries   {Malus  spp. seed for sowing from all countries RMP for public consultation} • 3 13. The host range for TBSV is wider than apple, and includes other economically important 
industries such as Pyrus , Solanum lycopersicum and Capsicum (CPC 2012).  
While TBSV latently infects apple  (i.e. does not cause symptoms) (Kegler and 
Schimanski 1982) , the virus is likely to have a low to moderate impact on other industries 
in New Zealand (MPI RA Mal us Nursery Stock, 2009). 
 
14. Apple Scar Skin Viroid  
The regulated status of  Apple scar skin viroid (ASSVd) is retained as a result of the 
current review .  ASSVd is not known to be present in New Zealand, and if identified in 
PEQ, MPI will take action on it. T he spread of ASSVd  is reported to be through seed, 
grafting and contaminated equipment. Seedlings germinated from ASSVd- positive seeds 
have been shown to have a 7.7% infection rate (Hyun et al. 2006) .  
 
15. The establishment of ASSVd would have an effect on fr uit production and quality in 
some apple cultivars. The host range for ASSVd includes other economically important crops, such as pear  (Pyrus ) (CPC 2012). The viroid is likely to have a moderate to high 
impact on economically important pip fruit industries  in New Zealand (MPI RA Malus  
Nursery Stock, 2009).  
 
16. The establishment of both these organisms in New Zealand are assessed as high risk 
organisms as any incursion would disrupt trade and potentially result in significant  
economic losses for New Zealand exp orters of material associated with these organisms.  
 
Risk Management  
17. All seed for sowing imported into New Zealand must undergo a number of steps to reduce the risk of the entry and establishment of regulated organisms. Table 1 provides a summary of the mitigation and verification steps that apple seed for sowing must go through to ensure freedom from regulated viruses/ viroids .  
 
18. All apple  seed for sowing imported into New Zealand must be imported under a permit to 
import, issued by MPI under the import he alth standard 155.02.05: Importation of Seed 
for Sowing. The permit to import is used to facilitate the import of the material, and details the specific import requirements for the particular consignment.  
 
19. Summary of mitigation and verification steps for  apple seed for sowing  are below:  
 
Step  Target organisms  Description of measures  Related documents  
Pre-export 
phytosanitary 
inspection  All • Prior to issuing a phytosanitary certificate, the 
exporting National Plant Protection Organisation 
(NPPO) must inspect  the seed in accordance with 
appropriate official procedures for freedom from 
visually detectable regulated pests, and to ensure 
the consignment conforms to New Zealand’s import 
requirements.  • 155.02.05:  Importation 
of Seed for Sowing  
• International Standards for Phytosanitary 
Measures
 ISPM 12. 
Guidelines for 
phytosanitary 
certificates (2001)  
On arrival 
verificat ion/ 
inspection  All • A 5kg sample (or the whole consignment if less than 
5kg) is inspected to verify compliance with the import 
requirements, and to achieve a 95% confidence level 
for freedom from visually detectable regulated pests.  • 155.02.05:  Importation 
of Seed for Sowing  
• MPI Border Clearance 
Procedures (internal 
MPI document)  
Post entry 
quarantine (PEQ)  All • The seed must be germinated, and the resulting 
seedlings grown in a level two  PEQ greenhouse for a 
minimum growing period of two years . • MPI operational 
standard 
PBC.NZ.TRA.PQ CON: Ministry for Primary Industries                                           {Malus  spp. seed for sowing from all countries RMP for public consultation}  • 4 Step  Target organisms  Description of measures  Related documents  
• The quarantine period will begin when the seedling s 
have two fully expanded leaves.  
• During the PEQ period,  all biolog ical and molecular 
testing must be completed.  
• Plants undergo growing season ins pection for visual 
symptoms of disease, and testing for pests and 
diseases of significant biosecurity concern.  Specification for the 
Registration of a Plant 
Quarantine or 
Containment Facility, 
and Operator
•  
155.02.05:  Importation 
of Seed for Sowing  
• MPI Operational Standard 
155.04.03: 
Diagnostic Facilities 
which undertake the 
identification or new 
organisms, excluding 
animal pathogens  
• MPI Post Entry 
Quarantine Testing 
Manual for Malus  
(Apple)  
• Border Clearance 
Procedures  
 
PRE-EXPORT PHYTOSANITARY INSPECTION AND CERTI FICATION  
20. The exporting National Plant Protection Organisation (NPPO) m ust inspect the 
consignment to confirm that it meets New Zealand’s import requirements. The exporting 
NPPO must verify the following pre -export activities have been completed : 
 
a) The seed for sowing has been inspected in accordance with appropriate official procedures and is found to be free from visually detectable regulated pests and diseases.  
 
21. When the exporting NPPO has verified that the consignment is compliant with the import 
requirements and no visually detectable regulated pests and diseases have been identified, 
a phytosanitary certificate can be issued. Following certification, the seed must be held in a manner to prevent infestation/reinfestation of regulated pests and diseases. 
 
ON ARRIVAL VERIFICATI ON OF PRE -EXPORT MEASURES  
22. On arrival in New Zealand, the MPI inspector will inspect the consignment to verify that 
the required pre -export measures have been met. This verification includes the following 
steps:  
 
a) Inspection of the phytosanitary certificate and permit to import to ensure compliance with the import requirements . 
b) Inspection of a 5kg sample (or the whole sample if under 5kg) to achieve a 95% confidence level for freedom from visually detectable regulated pests.  
  
Where the MPI inspector has verified that the consignment is compliant, the ins pector 
will authorise movement of the seed to the post entry quarantine facility specified on the permit to import.  
  
Ministry for Primary Industries   {Malus  spp. seed for sowing from all countries RMP for public consultation} • 5 POST ENTRY QUARANTINE (PEQ)  
23. All apple seed for sowing imported into New Zealand must enter a PEQ facility on 
arrival in New  Zealand.  The s eeds are germinated in PEQ and the resulting seedling s 
undergo a period of  quarantine  and specific testing  to ensure freedom from regulated 
pests and diseases.  The growing period begins  once the seedling s have two fully 
expanded leaves.  
GROWING SEASON INSP ECTION  
24. Material must undergo regular growing season inspections by a MPI inspector, to ensure freedom from  visually detectable regulated pests. Where visible signs of pests and 
diseases  are detected, samples may be collected and sent for diagnostic testing . 
 
25. The operator of the PEQ facility is also expected to undertake regular inspections of the plants during the growing season, and must notify the MPI inspector if any pest or disease symptoms are observed.  
TESTING FOR REGULATE D ORGANISMS OF SIGNIFICANT BI OSECURITY CONCERN 
26. Known pests and diseases of significant biosecurity concern require specific mitigation measures to  ensure that they do not enter and establish in New Zealand.  
 
 The following specific tests may be appropriate to detect regulated viruses  and viroids:  
• Biological tests: herbaceous indexing and woody indexing  
• Molecular tests: polymerase chain reaction (PCR)  
• Serological tests: enzyme linked immunosorbent assay (ELISA)  
 
27. The proposed testing requirements are based on the level of biosecurity ri sk associated 
with the organism on this pathway, and are identified in  sections 21 and 22.  
 With prior approval from MPI, internationally accepted testing methods will be accepted as equivalent to the requirements of the import health standard. 
The Post -Entry 
Quarantine Testing Manual for apple  describes appropriate testing protocols for each of 
the proposed tests .  
NON- COMPLIANCE  
 
28. Imported seed or seedlings  in PEQ (derive d from imported seed), w hich are not 
compliant with the  import requirements will not be eligible for biosecurity clearance. 
Where the inspector identifies that the seed consignment is not compliant, the importer will be given the option to make the consignment compliant (e.g. by treatment, where appropriate) or to reship or destroy the material.  
EQUIVALENCE  
29. If the seed is not able to meet the requirements of the import health standard, prior to import the importer may submit to MPI an application for assess ment of equivalent 
measures . Where MPI determines that the proposed alternative measures will provide an 
equivalent phytosanitary status, the details of the equivalence will be recorded on the permit to import.  
BIOSECURITY CLEARANCE  
 
30. Biosecurity clearance will only be given for seedlings in PEQ  if the inspector is satisfied 
that the following has occurred:  
• The imported seed and seedlings  in PEQ comply with the requirements of the 
import health standard;  Ministry for Primary Industries                                           {Malus  spp. seed for sowing from all countries RMP for public consultation}  • 6 • There are no discrepancies in the accompanying documen tation ; 
• The plant material does not display signs or symptoms of pests or disease ; 
• There has been no recent change in circumstances or knowledge that makes it 
unwis e to give biosecurity clearance  
 
31. Imported seeds that do not undergo growing season inspection in the greenhouse , and 
are not tested for regulated organisms , are not considered to be compliant with the 
requirements of the import health standard, and will not be eligible for biosecurity 
clearance.  
 
Proposed IHS requirements  
This section outlines t he proposed requirements for each regulated organism associated with 
apple seed for sowing.  
TOMATO BUSHY STUNT V IRUS  
32. TBSV is seed transmitted and is likely to have a low to moderate impact on other 
industries in New Zealand.  TBSV latently infects apple (i .e. does not produce 
symptoms), therefore MPI considers that  growing season inspection alone is not 
sufficient for this organism. PCR is a sensitive testing method  which can be used to 
detect this organism. Herbaceous indexing on the indicator species Chen opodium quinoa 
and Chenopodium amaranticolor  will also be used to  increase the likelihood of detecting 
all strains and variants of TBSV.  
 
Proposal  
33. MPI proposes t hat TBSV  is retained as a regulated pest, and that one of the following 
measures must be met p rior to biosecurity clearance:  
• Pest free area declaration (assessed by MPI)  
• Pest free place of production declaration (assessed by MPI)  
• PCR  and herbaceous indexing  (Cq and Ca) 
 
APPLE SCAR SKIN VIRO ID 
34. ASSVd  is seed transmitted. The establishment of ASSVd wo uld have an effect on fruit 
production and quality in some apple cultivars, and is likely to  have an impact on other 
industries  in New Zealand . PCR is a sensitive testing method  which can be used to 
detect this organism. Woody indexing on the indicators Ma lus x domestica  ‘Golden 
Delicious’ and ‘Red Delicious’  is also used to increase the likelihood of detecting all 
strains and variants of ASSVd.  
 
35. The current testing requirements for ASSVd include molecular (PCR) testing followed 
by woody indexing in the fie ld. These requirements are maintained. However once 
plants have tested negative for TBSV using PCR and HI, and have tested negative for ASSVd  using PCR , the trees can be transferred to a Level 1 PEQ facility for woody 
indexing . 
 
Proposal  
36. That ASSVd  is reta ined as a regulated pest, and that one of the following measures must 
be met prior to biosecurity clearance:  
• Pest free area declaration (assessed by MPI)  
• Pest free place of production declaration (assessed by MPI)   
Ministry for Primary Industries   {Malus  spp. seed for sowing from all countries RMP for public consultation} • 7 • PCR  and woody indexing ( Malus x domestica ‘Golden Delicious’ and ‘Red 
Delicious’)  
 
 
POST ENTRY QUARANTINE  
 
37. The IHS currently requires  apple  seed for sowing to be imported into a level three PEQ 
facility, germinated and grown for a minimum period of six months, and for the plants to 
undergo specifi c testing for regulated pests. The level of  PEQ required has been 
reviewed. As t here are no known insect vectors for TBSV  and ASSVd ,  MPI considers 
that a level two PEQ facility is adequate to contain these viruses/viroids in apple seedling s derived from i mported seed.  
 
38. In addition to seed transmission, TBSV  is transmitted through the soil so plants are 
required to be grown in pots on raised benches.  
 
39. In addition to seed transmission, ASSVd  is also spread through contaminated equipment, 
so good hygiene when handling plants will be required in PEQ . 
 
40. It is important that  the temperature in the facility does not exceed 25 ˚C, or thermotherapy 
of viruses can occur, making them less likely to be detected by PCR testing (but not necessarily eradicating them compl etely).  
 
41. A minimum period in Level 2 PEQ of three months  will commence once the plants have 
entered a period of active growth and have two fully expanded leaves , which should 
allow sufficient material for testing (molecular and biological). Testing for re gulated 
pests can occur when there is sufficient leaf material to be collected in accordance with section 7 of the MPI Post Entry Quarantine Testing Manual for apple .  The minimum 
period will be extended if material is slow growing, or pests are detected.  
 
42. After molecular testing and herbaceous indexing ha ve been completed, and assuming 
negati ve results for quarantine pests , the young trees can then be transferred into a Level 
1 PEQ facility to undergo woody indexing. Plants will remain in Level 1 PEQ for a  
minimum period of 2 years, to allow woody indexing results  on two years of fruit . The 
hygiene management protocols for ASSVd will remain in place for the duration of Level 
1 PEQ.  
 
Proposal  
43. MPI propose that the IHS requirements for apple be amended  to allo w seed to be grown 
in a Level 2 PEQ greenhouse for a minimum growing period of three months, undergoing grow ing season inspections and testing for regulated pests. Plants can be 
transferred to Level 1 PEQ after this time for a further two year  minimum period. 
 
 Ministry for Primary Industries                                           {Malus  spp. seed for sowing from all countries RMP for public consultation}  • 8 REFERENCES  
CPC (accessed February 2012) Crop Protection Com pendium on Internet. CAB International, 
Wallingford, UK; http://www.cabi.org/cpc/  
 
Hyun  RK, Lee SH, Lee DH, Kim JS, and Woo J . (2006) . Transmission of Apple scar skin 
viroid by Grafting, Us ing Contaminated Pruning Equipment, and Planting Infected 
Seeds. The Plant Pathology Journal 22(1) : 63-67. 
 
Kegler G, and Kegler H (1980) Research on natural transmission of tom ato bushy stunt virus 
in fruit trees. Tagungsbericht der Akademie der Landwirtschaftswissenschaften der 
Deutschen Demokratischen Republik  297- 302. 
 Kegler H, Kegler G, Kleinhempel H (1983) Epidemiological investigations on carnation 
ringspot virus and tom ato bushy stunt virus in fruit orchards. Zeszyty Problemowe 
Postepow Nauk Rolniczych 291: 155- 162. 
 Kegler G and Schimanski H -H (1982) Investigations on the spread and seed transmissibility 
of tomato bushy stunt virus in pome and stone fruit in the GDR. Archiv fur Phytopathologie und Pflanzenschutz  18(2):105- 109.