Draft Import Risk Analysis - Biosecurity New Zealand

Contents Page
Executive summary .........................................................................................................................1
1.Project background and process...................................................................................................4
1.1. Risk analysis background................................................................................................4
1.2. Risk analysis process and methodology..........................................................................5
1.3. References for chapter 1..................................................................................................7
2.Commodity and pathway descriptions .........................................................................................8
2.1. Commodity description...................................................................................................8
2.2. Introduction to the genus Malus......................................................................................8
2.3. Biology and ecology of Malus domestica.......................................................................9
2.4. The apple industry in New Zealand ..............................................................................10
2.5. Description of the existing import pathway ..................................................................11
2.6. References for chapter 2................................................................................................11
3.Hazard identification..................................................................................................................13
3.1. Potential hazard organisms............................................................................................13
3.2. Organisms and diseases recorded on Malus..................................................................15
3.3. References for chapter 3................................................................................................17
4.General phytosanitary measures for nursery stock ....................................................................18
4.1. Important generic risk factors .......................................................................................18
4.2. Collection, handling and storage of budwood...............................................................18
4.3. Disease symptom expression and testing......................................................................19
4.4. References for chapter 4................................................................................................23
5.Risk analyses – Viruses..............................................................................................................25
5.1. Apple latent spherical virus (ALSV).............................................................................25
5.2. Carnation ringspot virus (CRSV)..................................................................................29
5.3. Cherry rasp leaf virus (CRLV)......................................................................................35
5.4. Clover yellow mosaic virus (ClYMV)..........................................................................44
5.5. Horseradish latent virus (HRLV) ..................................................................................49
5.6. Sowbane mosaic virus (SoMV).....................................................................................51
5.7. Tomato bushy stunt virus (TBSV) ................................................................................53
5.8. Tomato ringspot virus (ToRSV) ...................................................................................58
5.9. Tulare apple mosaic virus (TAMV)..............................................................................66
6.Risk analyses – Viroids..............................................................................................................70
6.1. Apple dimple fruit viroid (ADFVd) ..............................................................................70
6.2. Apple fruit crinkle viroid (AFCVd) ..............................................................................75
6.3. Apple scar skin viroid (ASSVd)....................................................................................79
6.4. Peach latent mosaic viroid (PLMVd)............................................................................84
7.Risk analyses - Phytoplasma ......................................................................................................86
7.1. Candidatus Phytoplasma asteris (ApSL)......................................................................86
7.2. Candidatus Phytoplasma mali (AP, AT).......................................................................90
7.3. Candidatus Phytoplasma pyri (PD)...............................................................................97
8.Risk analyses - Diseases of unknown aetiology.........................................................................98
8.1. Apple blister bark agent ................................................................................................98
8.2. Apple brown ringspot agent ........................................................................................103
8.3. Apple bumpy fruit agent .............................................................................................107
8.4. Apple bunchy top agent...............................................................................................112
8.5. Apple dead spur agent.................................................................................................114
8.6. Apple decline agent.....................................................................................................118
8.7. Apple freckle scurf agent ............................................................................................122
8.8. Apple green dimple and ring blotch agent ..................................................................126
8.9. Apple junction necrotic pitting agent..........................................................................130
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