 
 
Risk Management Proposal  
Enabling imports of 
Prunus  cerasus  x Prunus canescens   
plants for planting  
 
 
 
 
 
 
 
 
 
 
 
Prepared for  public consultation   
by Plant Germplasm Imports  
Animal and Plant Health Directorate  
 
 
 
 
 
 
 
 
29 April  2022 
Disclaimer  
 
While every effort has been made to ensure the information in this publication is accurate, 
the Ministry  for Primary Industries does not accept any responsibility or liability for error of fact, 
omission, interpretation or opinion that may be present, nor for the consequences of any decisions 
based on this information.  
 
This publication is also available on the Ministry for Primary Industries  website at  
http://www.mpi.govt.nz/news -and-resources/publications/   
 
 
© Crown Copyright – Ministry  for Primary Industries   
Ministry for Primary Industries   Risk management proposal  to enable imports of Prunus cerasus x Prunus canescens  • 1 Contents  Page 
 
1 General information  2 
1.1 Submissions  2 
1.2 Context to consultation  3 
2 Enabling imports of Prunus cerasus  x Prunus canescens  4 
2.1 Purpose  4 
2.2 Background  4 
2.3 Proposal  4 
2.4 Justification  4 
3 Appendix 1 – P. cerasus x P. canescens technical advice  6 
  
   
2 • Risk management proposal  to enable imports of Prunus cerasus x Prunus canescens  Ministry for Primary Industries  1 General information  
 
1.1 Submissions  
The Ministry for Primary Industries (MPI) invites comment from interested parties on the 
proposal to enable imports of Prunus cerasus x Prunus canescens  under the import health 
standard Prunus Plants for Planting  (MPI.IHS.PRUNUS.PFP ). 
 
An import health standard  “specifies requirements to be met for the effective management of 
risks associated with arrival of craft or risk goods” (section 22 Biosecurity Act 1993).  
 
MPI encourages respondents to send comments electronically  to PlantImports@mpi.govt.nz . 
Please include the following in your submission:  
• The title of the consultation document in the subject line of your email;  
• Your name and title (if applicable);  
• Your organisation’s name (if applicable); and  
• Your address.  
 
However, should you wish to forward submissions in writing (hard copy), please send them to 
the following address to arrive by close of business on 13 May 2022:  
 
Plant Germplasm Imports  
Animal and Plant Health  Directorate  
Biosecurity New Zealand  
Ministry  for Primary Industries  
PO Box 2526  
Wellington 6140  
New Zealand  
 
Submissions received by the closure date will be considered during the development of the 
final import health standard . Submissions received after the closure date may be held on file 
for consideration when the issued import health standard  is next revised/reviewed.  
 
1.1.1 Official Information Act 1982  
Please note that your submission is public information , and it is MPI policy to publish 
submissions and the review of submissions on the MPI website. Submissions may also 
be the subject of requests for information under the Official Information Act 1982 
(OIA).  
 
The OIA specifies that information is to be made available to requesters unless there are 
sufficient grounds for withholding it, as set out in the OIA. Submitters may wish to 
indicate grounds for withholding specific information contained in their submission, 
such as information that is  commercially sens itive or personal. Any decision to withhold 
information requested under the OIA is reviewable by the Ombudsman . 
  
Ministry for Primary Industries   Risk management proposal  to enable imports of Prunus cerasus x Prunus canescens  • 3 1.2 Context to consultation  
 
1.2.1 Timing  
Consultation on this risk management proposal will run from 29 April  2022 to 13 May 
2022.  
 
1.2.2 International regulation of risk goods  
The World Trade Organisation Agreement on the Application of Sanitary and 
Phytosanitary Measures (the SPS Agreement) sets in place rules that protect each 
country’s sovereign right to take the measures necessary to protect the life  or health of 
its people, animals, and plants, while at the same time facilitating trade. It embodies and 
promotes the use of science -based risk assessments to manage the risks associated with 
the international movement of goods.  
 
The SPS Agreement guides how New Zealand sets standards and makes decisions 
related to biosecurity. In particular, it is important to maintain the standards of 
transparency and scientific rigour required by the SPS Agreement and to make 
decisions as quickly as possible. This will encourage other countries to comply with the 
rules of the SPS Agreement and also demonstrate that New Zealand’s strict controls are 
justified to countries that challenge them. (Balance in Trade [ISBN 978 -0-478-33881 -
2]) 
 
1.2.3 Domestic regulation of biosecurity risks associated with risk goods  
The New Zealand biosecurity system is regulated through the Biosecurity Act 1993. 
Section 22  of the Act describes a n import health standard and requires al l risk goods 
imported into New Z ealand to be managed by one.  
 
MPI is the New Zealand government ministry responsible for maintaining biosecurity 
standards for the effective management of risks associated with the importation of risk 
goods and craft into New Zealand (Part 3, Biosecurity Act 1993).  
 
MPI is committed to th e principles of transparency and evidence -based technical 
justification for all phytosanitary measures, new and amended, imposed on importing 
pathways. MPI periodically reviews all  import health standards, related documents, and 
other standards so that the  legal requirements are clear , and information is consistently 
presented and is as easy as possible to understand.  
   
4 • Risk management proposal  to enable imports of Prunus cerasus x Prunus canescens  Ministry for Primary Industries  2 Enabling imports of Prunus cerasus  x Prunus canescens  
 
2.1 Purpose  
The purpose of this risk management proposal  is to:  
- propose making Prunus cerasus x Prunus canescens  eligible for import under the 
import health standard Prunus Plants for Planting , MPI.IHS.PRUNUS.PFP  (Prunus 
standard) ; and 
- propose risk management measures for importing  P. cerasus x P. canescens  plants for 
planting . 
 
2.2 Background   
The Prunus  standard : 
- includes import requirements for species and hybrids of Prunus ; 
- was issued under section 2 4A of the Biosecurity Act 1993 ; 
- applies  to Prunus plants for planting  imported into New Zealand from other  countries 
and territories ; and 
- was last amended  on 20 December  2021 .  
 
The Plants Biosecurity Index (PBI) records the species eligible for import under the Prunus 
standard. Therefore , the PBI will be amended to enable imports of P. cerasus x P. canescens.   
 
There are no text amendments to the Prunus standard. Consequently, the Prunus standard has 
not been provided as an accompanying document with this proposal.  
 
2.3 Proposal  
MPI propose s to manage the biosecurity risk from imported P. cerasus  x P. canescens 
through the current requirements of the Prunus standard.  
 
To make P. cerasus x P. canescens  eligible for import under the Prunus  standard , MPI 
propose to amend  the PBI to include the following import specifications for 
P. cerasus  x P. canescens . 
- Nursery stock “ see MPI.IHS.PRUNUS.PFP ” 
- Seed for sowing “requires assessment”.  
 
2.4 Justification  
Based on the information below, t his proposal is feasible  and will appropriately manage 
imports  of P. cerasus  x P. canescens . 
 
2.4.1 Biosecurity risk  of P. cerasus  x P. canescens  
Based on currently available information , the current requirements of the Prunus 
standard will appropriately manage the biosecurity risk associated with 
P. cerasus  x P. canescens plants for planting.  P. cerasus x P. canescens was not found 
to have  any pests or diseases uniquely associated with it when compared to other 
eligible Prunus species1.  
 
                                                      
1 See appendix 1  (P. cerasus x P. canescens technical advice ) for more detail.   
Ministry for Primary Industries   Risk management proposal  to enable imports of Prunus cerasus x Prunus canescens  • 5 2.4.2 New organism risk  of P. cerasus  x P. canescens  
There is no new organism risk associated with P. cerasus  x P. canescens . The 
Environmental Protection Authority made an official determination2 under section 26 of 
the Hazardous Substances and New Organisms Act 1996 that P. cerasus  x P. canescens  
is not a new organism for the purposes of the Act . 
2.4.3 Feasibility of proposal  
Importing P. cerasus  x P. canescens under the current requirements of the Prunus  
standard is feasible  because:   
- there are no new requirements  for Prunus needed to manage the risk from 
P. cerasus x P. canescens ; and  
- imports of other eligible Prunus  species have already been occurring successfully.  
 
  
                                                      
2 For details, s ee application APP204379  on the Environmental Protection Authority website .  
6 • Risk management proposal  to enable imports of Prunus cerasus x Prunus canescens  Ministry for Primary Industries  3 Appendix 1 – P . cerasus x P . canesc ens technical advice  
Technical advice on:  Addition of Prunus cerasus  x Prunus canescens  to the Plant Biosecurity 
Index to allow importation of this hybrid under current import requirements for Prunus  nursery stock  
Purpose of document  
The purpose of this document is to assess whether the biosecurity risks associated with the  hybrid 
Prunus cerasus  x Prunus canescens  are managed by existing measures for Prunus in the import health 
standard (MPI.IHS. PRUNUS.PFP) (MPI 2020). This would enable Germplasm Imports to decide 
whether this  hybrid can be added to the Plants Biosecurity Index (PBI) and allow its importation 
under the existing import conditions for permitted Prunus species, or if additional measu res are 
required.  
The specific risk management question considered in this advice is:  
1. Are there any pests or diseases associated with hybrids of P. cerasus  x P. canescens  that 
would not be managed by current measures in the Prunus  plants for planting IHS?  
Summary of advice  
• Based on currently available information, the biosecurity risks associated with importation of 
dormant cuttings of Prunus cerasus  x Prunus canescens  are likely to be managed by existing 
import conditions for Prunus species currently listed on the Plant Biosecurity Index, which 
are eligible for import under Prunus  Plants for Planting IHS (MPI 2020).  
• No pests or diseases were found to be uniquely associated with P. cerasus  x P. canescens 
compared to other Prunus  species that are currently eligible for import.  
Supporting information  
Commodity and pathway description  
Commodity description  
The hybrid Prunus canescens  Bois (1904) (gray -leaf cherry) x Prunus cerasus  Linnaeus (1753) (dwarf 
cherry) is a cherry rootstock popular amongst cherry growers for its dwarfing and productive 
attri butes (Long and Kaiser 2010). In addition, the hybrid is known for P. canescens -derived 
resistance to diseases like Cherry Leaf Spot caused by the fungus Blumeriella jaapii (Andersen et al. 
2018) and viruses such as Prunus necrotic ringspot virus  (PNRSV) and Prune dwarf virus  (PDV) 
(Gruppe & Schmidt 1994; Lang 2000).  
For the purpose of this advice, the commodity is described as dormant cuttings of Prunus cerasus x 
Prunus canescens. Dormant cuttings are budwood/dormant cuttings from aerial parts on ly. These 
may include stems, shoots, terminal, and axillary buds (MPI 2019).  
 
Pathway description  
The PBI currently lists 46 Prunus species that can be imported as nursery stock (dormant cuttings and 
plants in tissue culture) under the Prunus  import heal th standard MPI.IHS.PRUNUS.PFP  (MPI 2020). 
The standard states the requirements for importation of Prunus  nursery stock and includes a list of 
regulated pests and diseases for the genus. Unde r current provisions , all imported Prunus  nursery  
Ministry for Primary Industries   Risk management proposal  to enable imports of Prunus cerasus x Prunus canescens  • 7 stock must meet the general requirements (section 1), specific requirements (section 2) and 
additional requirements detailed in the standard (section 3). The import requirements (as per 
MPI.IHS.PRUNUS.PFP) are summarised below:  
• Commodities must meet “basic” import requirements for all nursery stock, as specified in 
section 1 of the IHS.  
• An import permit is required, and a phytosanitary certificate must accompany all 
consignments certifying that the Prunus  nursery stock, has been treated for regulated insects 
and mites (dormant cutting only), inspected and found to be free of any visually detectable 
pest.  
• Cuttings can be imported either under an Export Plan, from an MPI -approved offshore 
facility, or neith er of these arrangements.  
• All cuttings must be imported into post -entry quarantine either Level 2, 3A or 3B depending 
on whether they were imported under an Export Plan, from an MPI -approved facility or non -
approved facilities. The period in post -entry qu arantine varies from 9 to 21 months 
depending on the source of the cuttings. All dormant cutting must be dipped in 1% sodium 
hypochlorite for a minimum of 2 minutes upon arrival to in the PEQ facility.  
• While in post -entry quarantine imported material is t ested for quarantine pests listed in the 
Import Health Standard. Full details of all requirements can be found in the Import Health 
Standard . 
Based on the commodity class (germplasm), dormant  cuttings of Prunus cerasus x Prunus canescens  
are categorised as being a high biosecurity risk (Table 1).  
 
Table 1: Categorization of Prunus cerasus x Prunus canescens  dormant cuttings according to pest 
risk and existing import requirements on the Prunus  plants for planting pathway.  
 
Question  Rating and Factors considered  
What is the relative risk 
associated with the 
commodity class?  High  
• Germplasm: they are not processed  and are intended for the 
propagation of plants for planting and distribution (refer to 
ISPM 32: Categorization of commodities according to their pest 
risk).3  
What is the relative risk 
associated with the type 
of material making up 
the commodity?  Moderate -High  
• Dormant cuttings (35 -60 cm long with 3 -9 buds) – compared to 
seed – may have a higher number of associated pests and 
diseases.  
• Symptoms of pathogenic infection are often not visible on 
dormant cuttings, which increases the risk of diseases en tering 
undetected on the commodity.   
                                                      
3 ISPM 32 https://www.ippc.int/static/media/files/publication/en/2016/01/ISPM_32_2009_En_2015 -12-
22_PostCPM10_InkAmReformatted.pdf   
8 • Risk management proposal  to enable imports of Prunus cerasus x Prunus canescens  Ministry for Primary Industries  Question  Rating and Factors considered  
How likely is the 
commodity to carry pests 
that can establish in New 
Zealand?  High  
• Climate match index (CMI) values for countries in which P. 
cerasus  and P. canescens  are native or have been introduced 
are between 0.7 and 0.9;  indicating a 70 -90% similarity to the 
New Zealand climate, which is sufficient to allow diseases 
present in those areas to establish in New Zealand (Phillips et 
al. 2018)  
• Cuttings may carry sys temic diseases, which can be 
transmitted to plants propagated from the cuttings under 
conditions suitable for pathogen multiplication  
How likely is the 
commodity to carry pests 
which cause major 
impacts in New Zealand? 
What are the values 
associated with  the 
commodity species and 
the related species in 
New Zealand?  High  
• The hybrid, Prunus cerasus  x Prunus canescens  is likely to carry 
pests and diseases that  affect the parent species or other 
Prunus  species (Lang, 2000).   
• Prunus  spp. contribute significantly to New Zealand’s economy; 
Prunus  exports and domestic sales during the 2019 -2020 
summer season were worth 55.5 and 49.6 million respectively, 
to New Zealand. Of the total export revenue, 92.5% is solely 
from cherry exports ( NZ Horticulture Export Authority 2021). 
Many pests and diseases of Prunus  species are known to affect 
host plants in other genera (MPI 2019).  
What is the level of 
knowledge about the 
pests associated with the 
commodity and related 
species in New Zealand 
and overseas?  High  
• Prunus species have a wide geographic distribution and are 
widely cultivated and traded internationally. Therefore, there 
is plenty of scientific literature on pests and diseases 
associated with the genus.  
• Information on pests and disease s recently associated with 
Prunus  is also available via MPI’s emerging risk system (ERS).  
• Information regarding the hybrid  P. cerasus x P. canescens is 
mostly regarding P. canescens -derived resistance to diseases in 
new cherry hybrids (Andersen et al. 2018 ) and methods to 
enhance root growth from grafted vegetative material 
(Exadaktylou et al. 2006) and little information was obtained 
on susceptibility of the hybrid to diseases (Franken -Bembenek 
2008).   
 
Procedure for hazard identification  
For the purposes of this technical advice, only diseases associated with P. cerasus  x P. canescens  and 
the parent species “ Prunus canescens ” (Table A.1 ) were considered, because the parent plant 
“Prunus cerasus ” is already included in the Plant Biosecurity  Index (PBI). In addition, all pests and 
diseases that are reported to be present in NZ were excluded, as well as pests and diseases not 
associated with the commodity, for example: soil -borne fungi, pests and diseases associated only 
with leaves or fruits.   Insects and mites were not considered as these are managed by pre -import 
treatments specified in the Prunus Plants for Planting IHS.   
Ministry for Primary Industries   Risk management proposal  to enable imports of Prunus cerasus x Prunus canescens  • 9 Searches were performed in Google Scholar, EPPO global database, and CABI (crop protection 
compendium, abstracts and datasheets) using the CABI Horizons Scanning Tool. The Google scholar 
search terms “ Prunus cerasus  x Prunus canescens  + diseases” and “ Prunus canescens  + diseases”, 
“Gisela hybrid + diseases” were used to obtain information relevant  to the question stated in the 
“purpose of document” section above. The MPI Emerging Risks System (ERS) was also checked for 
alerts of pests and diseases associated with Prunus species to identify any new emerging risk 
associated with the commodity and pat hway.  
 
Results  
No pests or diseases were found to be uniquely associated with the hybrid  Prunus cerasus x Prunus 
canescens,  compared with other Prunus  species  
• Google Scholar search using “ Prunus cerasus x Prunus canescens + diseases” brought up 632 
results. The first six pages (60 results) were screened and most of these were related to P. 
canescens -derived resistance to diseases and pest and diseases that affect other Prunus  
species. None of the information gathered was re lated to pest and diseases uniquely 
associated to the hybrid P. cerasus  x P. canescens .  
• Another Google scholar search using “ Prunus canescens  + diseases”, brought up 3,530 
results. The first 6 pages (60 results) were screened and none of these included an y diseases 
uniquely associated to this species. Most of the literature found was related to 
phytohormone related resistance, resistance screening of various Prunus  spp., of which P. 
canescens was one of the species included . The Google search was conducted  following the 
assumption that the most relevant information would be in the earlier pages of the search, 
therefore when the Google scholar search results returned became dominated by topics 
unrelated to pest and diseases for example: genetic identificatio n of hybrids or methods to 
improve rooting of hybrids, the search was stopped.  
• A search was performed on Google patents using as search term, the original name of the 
hybrid patent (as recognized by US Patents) for example, GI 148/1 for the hybrid “Gisela  5”. 
Information about the hybrid’s characteristic and resistance to diseases was obtained, and 
information about susceptibility to diseases already present in other Prunus  species was 
reported (Gruppe & Schmidt 1994).  
• A search on CABI (crop protection compendium, abstracts and datasheets) was performed 
using CABI’s Horizons scanning tool.  The hybrid P. cerasus  x P. canescens  was not found 
among CABI’s host list, thus all the diseases found were associated to Prunus  spp. and only P. 
cerasus  was found pertaining to this advice.  
• This hybrid is not recorded in the EPPO Global database. Therefore, the search on this 
database was focused on diseases associated with the parent plant, P. canescens . No 
diseases were found t o be uniquely associated to this species compared with other Prunus  
species.  
• A search of MPI’s Emerging Risk System (ERS) did not show diseases uniquely associated with 
this hybrid.  
 
The pests and diseases found associated with the hybrid Prunus cerasus  x Prunus canescens  are 
also associated with other Prunus  species and are currently included in (and managed by) the 
Prunus  IHS (MPI.IHS.PRUNUS.PFP)  
• Diseases found to be associated with the hybrid  P. cerasus x P. canescens also affect  other 
Prunus  species Table A.1 .   
10 • Risk management proposal  to enable imports of Prunus cerasus x Prunus canescens  Ministry for Primary Industries  • The diseases reported in Table A.1  are considered to be managed by current measures under 
Prunus  IHS (MPI 2020) which were briefly described in the pathway description.   
• The phytoplasma ‘Candidatus Phytoplasma prunorum ’ a bacteria associated with  P. cerasus  x 
P. canescens , as well as in other Prunus  species does not appear as a regulated pest, however 
it is considered to be included under ‘Candidatus Phytoplasma’ spp. which is listed as a 
regulated pest in the Schedule 1: Regulated pest list of the Prunus IHS (MPI 2020). This disease 
is likely to be detected by PCR using universal primers of Phytoplasma already present in New 
Zealand as reported in the list of regulated pests of Prunus  (MPI 2020).     
• The X -disease phy toplasma, commonly known as Western X -disease, is not listed in the Prunus 
pest list. However, this phytoplasma which is listed as unassessed in the Prunus IRA is likely to 
be managed by measures for other phytoplasmas in the Prunus IHS (i.e. PCR using uni versal 
phytoplasma primers present in New Zealand) (MPI 2020).  
• Unassessed species, as described in the Prunus IRA  are pathogens that met the criteria for 
being quarantine pests, but already had additional measures in the Nursery Stock IHS 
155.02.06  (MPI 2019b) that were included in the Prunus IHS. Therefore, the f ollowing 
unassessed species: Tomato ringspot virus (ToRSV), Cherry rosette virus (CRLV) and Raspberry 
ringspot virus (RRV) are considered to be managed by the current Prunus IHS (MPI 2020).  
Based on the commodity class (germplasm) and the material making up the commodity (dormant 
cuttings of hybrids Prunus cerasus  x Prunus canescens ), the level of risk associated with this pathway, 
in the absence of pest management measures is moderate -to-high, but the level of risk is considered 
to be negligible or very low, if the imported material complies with existing import requirements in 
the import health standard for Prunus species currently listed on the PBI.  
References  
Andersen, K L; Sebolt, A M; Sundin, G W; Lezzoni, A F (2018) Assessment of the inheritance and 
tolerance in cherry ( Prunus  sp.) to Blumeriella jaapii , the causal agent of cherry leaf spot. Plant  
pathology , 67(3): 682 -691.  
CABI Horizons Scanning Tool https://www.cabi.org/horizonscanningtool  accessed [05/2021].  
EPPO Global Database https://gd.eppo.int/  accessed [05/2021].  
ERS (2021) Emerging Risks System. Internal MPI database accessed [12/05/2021].  
Exadaktylou, E; Thomidis, T; Tsipouridis, C; Grout, B W W (2006) Factors influencing the rooting of 
Gisela 5 ( Prunus cerasus  x Prunus canescens ) cherry rootstock hardwood cuttings. Australian Journal  
of Experimental Agriculture , 46(12) DOI: 10.1071/EA05094.  
Franken -Bembenek S (2008) Reaction of Gisela rootstocks® to pathogens. In: Fifth International 
Cherry Symposium, 795:303 -309. ISHS, Bursa, Turkey.  
Gruppe, W; Schmidt, H (1994) Cherry rootstock GI 148/1. (US Patent No. 8,954). United States 
Patent. 
https://patents.google.com/patent/USPP8954?oq=Cherr y+rootstock+GI+148%2f1+%2b+gruppe  
Lang, G A (2000) Precocious, dwarfing, and productive – how will new cherry rootstocks impact the 
sweet cherry industry. HortTechnology , 10(4):719 –725.  
MPI (2020) MPI.IHS.PRUNUS.PFP –Importation of Prunus Plants for Plant ing. Available at:  
https://www.mpi.govt.nz/dmsdocument/38693/direct  accessed [05/2021].   
Ministry for Primary Industries   Risk management proposal  to enable imports of Prunus cerasus x Prunus canescens  • 11 MPI (2019a) Import Risk Analysis: Prunus  plants for planting. Version 1. May 2019.  Ministry for 
Primary Industries, New Zealand.  
MPI (2019b) Importation of Nursery Stock, Standard 155.02.06. (2021) Ministry for Primary 
Industries, New Zealand.  
New Zealand Horticulture Export Authority (2021) Summerfruit (cherries, apricots, peaches, 
nectarines, plums) – Summerfruit industry profile https://www.hea.co.nz/2012 -05-11-03-05-
28/summerfruit -trade . 
NZOR (2021) New Zealand Organisms Register http://www.nzor.org.nz/search  accessed [05/2021].  
NZFungi2 (2021) New Zealand Fungi and Bacteria. Manaaki Whenua Landcare Research Database 
https://nzfungi2.landcareresearch .co.nz/  accessed [05/2021].  
Phillips C B; Kean J M; Vink C; Berry J (2018) Utility of the CLIMEX match climates regional algorithm 
for pest risk analysis. An evaluation with non -native ants in New Zealand. Biological Invasions , 20: 
777-791.  
Uyemoto, J K; K irkpatrick, B C; Cummings, J N (1991) Susceptibility of selected cherry clones and 
related species to Western X -disease. HortScience , 26(12): 1510 -1511.  
Veerakone, S; Tang, J Z; Ward, L I; Liefting L W; Perez -Egusquiza, Z; Lebas, B S M; Delmiglio, C; 
Fletc her, J D; Guy, P L (2015) A review of the plant virus, viroid, liberibacter and phytoplasma records 
for New Zealand. Australasian Plant Pathology , 44:463 -514.  
   
12 • Risk management proposal  to enable imports of Prunus cerasus x Prunus canescens  Ministry for Primary Industries  Appendix A  
Table A.1. List of diseases associated with the hybrid Prunus cerasus  x Prunus canes cens  and the 
parent species P. canescens.  
Scientific 
name  Common 
name  Type of 
causativ
e agent  Associate
d Prunus 
species  Regulated/assesse
d in IHS or IRA  Reference  Date 
accessed  
‘Candidatus 
Phytoplasm
a prunorum’  Apricot 
chlorotic 
leafroll; 
Europea
n stone 
fruit 
yellows  Bacteria  Prunus 
canescens
; Prunus 
cerasus  x 
Prunus 
canescens  Regulated under 
‘Candidatus  
Phytoplasma sp.’  EPPO*  11/05/202
1 
X-disease 
Phytoplasm
a Western 
X-disease  Bacteria  Prunus 
cerasus x 
Prunus 
canescens  Not regulated or 
assessed  Uyemoto 
et al. 1991   
Apiosporina 
morbosa  Black 
knot  Fungi  Prunus 
canescens  Regulated in IHS  EPPO*  7/05/2021; 
11/05/202
1 
Peach 
mosaic virus  
(PcMV)   Virus  Prunus 
canescens  Regulated in IHS  EPPO*  11/05/202
1 
Plum pox 
virus  (PPV)  Sharka  Virus  Prunus 
canescens  Regulated in IHS  Franken -
Bembenek
, 2008   
Tomato 
ringspot 
virus  
(ToRSV)   Virus  Prunus 
canescens  Unassessed in IRA  EPPO*  11/05/202
1 
Cherry 
rosette virus  
(CRV)   Virus  Prunus 
cerasus x 
Prunus 
canescens  Unassessed in IRA  Buser et al 
1999; 
Franken -
Bembenek
, 2008   
Raspberry 
ringspot 
virus  (RRV)   Virus  Prunus 
cerasus x 
Prunus 
canescens  Unassessed in IRA  Buser et al 
1999; 
Franken -
Bembenek
, 2008   
*Diseases listed in the European and Mediterranean Plant Protection Organization (EPPO) under the 
host plant P. canescens  are categorized under the host plant Prunus  spp. therefore diseases might 
not be uniquely associated with P. canescens . 