- 4.1 Erwinia amylovora
- 4.1.1 Infestation of the calyx-end of fruit
- 4.1.2 Bacterial infection of mature fruit in
orchard or after harvest
- 4.1.2.1 Strategy 1 - establishment of registered export blocks (REBs) free from fire blight disease
- 4.1.2.2 Strategy 2 - Establishment of detection zones
- 4.1.2.3 Strategy 3 - Disinfestation of harvesting bins
- 4.1.2.4 Strategy 6 - Sorting, grading and packing procedures
- 4.1.2.5 Strategy 7 - Phytosanitary inspection and certification
- 4.1.2.6 Strategy 8 - Registration of exporters and packing houses
- 4.1.2.7 Strategy 9 - Maintenance of fruit security in storage
- 4.1.2.8 Strategy 10 - AQIS audit of New Zealand apple production and packing house systems
- 4.1.2.9 Strategy 11 - On-arrival inspection
- 4.1.3 Epiphytic contamination of fruit surfaces
- 4.1.4 The presence of trash with imported fruit
4. Phytosanitary measures to manage assessed risk
4.1 Erwinia amylovora
As New Zealand has stated in previous sections, the risk posed by the unrestricted importation of New Zealand apple fruit is negligible. Therefore no measures are required to further reduce risk and the risk from unrestricted importation is below Australia's stated ALOP. However, even if the level of risk assessed by AFFA was deemed to be an accurate interpretation of the scientific evidence, New Zealand believes that the phytosanitary measures proposed by AFFA are not the least trade restrictive measures available and do not bear an objective, rational relationship to the risks identified. In many cases measures are linked only to the mere possibility of risk, rather than to a probability or likelihood.
AFFA has stated that the purpose of the proposed risk management measures is to reduce the risk of:
- bacterial infection of mature fruit in orchard or after harvest;
- infestation of the calyx-end of the fruit;
- epiphytic contamination of fruit surfaces; and
- the presence of trash with imported fruit (p.113, l.27).
AFFA has also given some indication that calyx infestation is the main risk that they wish to manage - "bacterial infestation during blossoming is of primary concern because the bacteria may be subsequently protected from a disinfestation treatment". Our comments are arranged on the basis of these perceived risks, and relate to the justification of the measures proposed to reduce this perceived risk.
In proposing measures to manage risk it is necessary for an importing country to demonstrate a rational relationship between the risk and the proposed measure (refer para 193 of the Hormones case10). It is also necessary that the measures proposed are the least trade restrictive available (FAO, 1995). New Zealand requests that AFFA makes more transparent the extent to which each measure reduces risk. It is of concern that some measures are neither necessary nor contribute in any significant way to risk management. Many of these measures have the potential to be very trade restrictive through cost and delays to consignments, but it is not clear that the measure is either necessary or the least trade restrictive measure available.
New Zealand finds that the requirement for registered orchard blocks to be subject to three inspections in the season of export and in the previous season is not based on the risk assessment and is more trade restrictive than necessary.
New Zealand further considers that:
- there is no justification for the establishment of detection zones;
- the segregation and disinfestation of bins is unsupported by data;
- the disinfestation of fruit by chlorine dipping is redundant;
- the requirement for a one metre separation of product in cold storage is unjustified;
- the requirement for packing fruit into cartons before storage is unsupported;
- the on-arrival inspection of fruit adds no further security to the system; and
- the proposed audit schedule is more onerous than that required in the case of other completed draft IRAs.
| New Zealand requests that AFFA review the above measures. |
4.1.1 Infestation of the calyx-end of fruit
The measures proposed in the draft IRA to reduce the infestation of the calyx-end of the fruit include Strategy 1 (establishment of registered export blocks (REBs) free from fire blight disease) and Strategy 2 (establishment of detection zones).
4.1.1.1 Strategy 1 - establishment of registered export blocks (REBs) free from fire blight disease
AFFA is proposing that, in order to reduce the risk of calyx-end infestation of mature fruit, REBs are free from fire blight as determined by visual inspection at flowering, fruitlet and harvest over a two-year period. In doing so AFFA appears to be imposing a requirement of orchard freedom from E. amylovora in order to reduce the risk of infestation / infection of fruit. AFFA has not demonstrated the justification for three inspections in each of two years. New Zealand submits that a similar level of assurance could be achieved by a single orchard inspection. New Zealand believes that 6 inspections over 2 years is not the least trade restrictive measure available to Australia.
WTO jurisprudence clarifies that there must be a rational relationship between a measure and the risk that it is intended to reduce (i.e., the measure must be based on a risk assessment). It is generally accepted (as described in draft IRA) that calyx infestation occurs when epiphytic bacteria are retained on the remnant flower parts at the end of the blossom period and are subsequently incorporated into the calyx end of the apple fruit. This being the case, epiphytic bacteria in the calyx of apples can only be transmitted at blossom time. It seems reasonable to suggest that mature fruit from orchards inspected at petal fall, or shortly thereafter, and found free from fire blight would also be free from epiphytic E. amylovora in the calyx. As the intent of the measure is to reduce (not eliminate) the risk of calyx-end infestation of mature fruit the only justifiable timing of the inspection is at blossom (petal fall) or at fruitlet stage when symptoms would be expressing themselves in the orchard.
New Zealand would also like to raise the principle of non-discrimination (FAO, 1995). AFFA did not require that production areas in Japan, Korea or China be surveyed for two seasons and found free from fire blight before permitting the export of host fruit to Australia. Nor did Australia conduct two years of surveillance (at appropriate times for detection) in order to declare freedom from fire blight following the confirmation of E. amylovora in the Royal Botanic Gardens, Melbourne.
| New Zealand is most concerned that this measure (i.e., six orchard inspections over two years) is more trade restrictive than necessary. |
4.1.1.2 Strategy 2 - establishment of detection zones
On the basis of the literature, there appears to be no justification for, or rational relationship between, the establishment of detection zones to reduce the risk of calyx-end infestation of mature fruit, or rational link between this measure and the risk assessment. As is so clearly stated by AFFA - "there is no consensus on the exact purpose, or therefore specifications of the detection zone" (p.117, l 127).
No data have been presented by AFFA to link the requirement for a 50 m detection zone with epiphytic infestation of the calyx of mature fruit. In only one instance has an author recovered E. amylovora from the calyx of an apple fruit from an orchard apparently free from fire blight. In that instance (van der Zwet et al. 1990) there was fire blight in an orchard less than 10 m away (Roberts, pers. comm., 2000). It is also unclear whether the recovery of E. amylovora reported by van der Zwet et al. (1990) was from mature fruit, as these were collected over a 3 month period (the same variety from the same orchard). Hale et al. (1987) reported a 94% decline in calyx infestation of apple fruit between fruitlet stage and harvest, so it is likely that the bacteria recovered by van der Zwet et al. (1990) were from immature fruit. This is consistent with all other reports from the literature.
| New Zealand believes that there is no rational relationship between the risk of calyx-end infestation of mature fruit and the requirement for a 50 m detection zone. |
4.1.2 Bacterial infection of mature fruit in orchard or after harvest
As New Zealand has discussed in previous sections we believe that the risk posed by infected fruit is negligible. Even if AFFA's assessment of risk is deemed appropriate, New Zealand believes that the 9 measures proposed by AFFA in order to reduce the risk of bacterial infection of mature fruit in orchard or after harvest are far more restrictive than is necessary. Given that bacterial infection of mature fruit is exceedingly rare (refer to the expert opinion cited in section 3.1.1.1 of this document) the imposition of 9 separate measures would seem to be excessive.
| New Zealand suggests that many of the measures do not substantially reduce risk and are trade restrictive. |
4.1.2.1 Strategy 1 - establishment of registered export blocks (REBs) free from fire blight disease
If infected fruit did indeed pose a risk of introduction of fire blight to Australia, then the measures to reduce that risk would have to be based on the mechanism for fruit infection. Fruitlets that are infected at blossom remain undersized and attached to the cluster base (AFFA, 2000). These fruit infected by this means would therefore not be harvested and exported. Orchard inspection at blossom is therefore not relevant. Also, twig cankers are inactive by the harvest period (Dueck, 1974), so an inspection at harvest is not relevant either (in normal orchard practice any disease would be pruned out during the growing season anyway). Presumably inspection should be timed to prevent "secondary spread of the disease, which is of particular concern after blossoming and before fruit formation" (AFFA, 2000). Inspection should be timed to coincide with this period.
| New Zealand suggests that if necessary, any such inspection should coincide with the fruitlet stage. |
4.1.2.2 Strategy 2 - Establishment of detection zones
There have been no isolations of endophytic E. amylovora from fruit located more than 15 cm from infection sites, other than by van der Zwet et al. (1990) who isolated E. amylovora from surface sterilised fruit taken from an orchard free of symptoms but less than 10 m from an infected orchard (Roberts, pers. comm., 2000). Given this evidence from the literature, New Zealand cannot establish any rational link between the assessed risk posed by fruit infections and the establishment of a buffer zone.
AFFA concedes that there is no consensus on the purpose of a detection zone. The only statement indicating a purpose is "A detection zone would lower the risks of wind or water borne inoculum drops that could cause secondary spread of the disease, which is of particular concern after blossoming and before fruit formation". Inspection at harvest would not, then, contribute to risk reduction. The key time to inspect a detection zone would be at fruitlet stage if indeed this poses a risk.
AFFA also states that detection zones would serve as an "early detection mechanism". This is unlikely to be of any value, as fire blight does not infect the edges of an orchard before any other part of the orchard.
| New Zealand considers that there is no justification for a detection zone. |
4.1.2.3 Strategy 3 - Disinfestation of harvesting bins
In the draft IRA it has been established that E. amylovora may survive on wooden bins for a number of months. What has not been established is whether bacteria from an infected fruit can be transmitted to a wooden bin and then onto a fruit resulting in infection. AFFA has provided no data to support this theory. Presumably fruit would have to be damaged in order for fruit infection to be initiated, and damaged fruit would normally be graded out during packing.
| The imposition of phytosanitary measures must be based on the probability of risk, not the mere possibility of risk, so New Zealand asks that AFFA provide justification for the requirement for disinfestation of bins. |
4.1.2.4 Strategy 6 - Sorting, grading and packing procedures
As stated in 3.1.1.2, normal pack house procedures would reduce any risk of endophytic infection caused by contact with contaminated bins.
New Zealand is concerned that this measure is highly prescriptive in that it requires fruit to be packed into cartons before storage. In many instances fruit are packed into bins and then stored, before being repacked from cold store into cartons. It is also possible that exporters may wish to export fruit in bins.
| New Zealand believes that the requirement to pack fruit into cartons before storage is more trade restrictive than necessary. |
4.1.2.5 Strategy 7 - Phytosanitary inspection and certification
New Zealand does not believe that phytosanitary inspection will significantly reduce the risk of endophytically infected fruit being exported, yet it adds cost to the export programme and is therefore an impediment to trade. Three of the experts consulted by AFFA responded that it is not possible to detect endophytic infection at pre-export visual inspection. One further expert did not respond, and Wimalajeewa stated that it would not be possible unless symptoms are present in the fruit. Although a phytosanitary inspection may be required for other pests, the training, documentation, and possible laboratory testing of fruit adds significantly to the cost of the export programme without contributing to phytosanitary security.
| New Zealand considers that phytosanitary inspection does not decrease the risk of endophytically infected fruit being exported and is an impediment to trade. |
4.1.2.6 Strategy 8 - Registration of exporters and packing houses
New Zealand requests that the requirement for AQIS be notified of all changes in registration of exporters and pack houses be modified to a requirement for MAF to maintain a register of blocks, exporters and pack houses and that these records are available to AQIS on request. Notification of every change in registration is onerous and costly, and adds no security to the system.
| New Zealand requests a modification of this requirement to allow MAF to maintain a register available to AQIS on request. |
4.1.2.7 Strategy 9 - Maintenance of fruit security in storage
The requirement for a 1 m separation of fruit in cold storage is not justified. AFFA has not supported this with any technical documentation to suggest that E. amylovora is capable of spreading 1 m in cold storage.
| New Zealand believes there is no technical justification for a 1 m separation of fruit in cold storage. |
4.1.2.8 Strategy 10 - AQIS audit of New Zealand apple production and packing house systems
AFFA is requiring two full audits of MAF systems. This does not take into account the understanding AQIS already has of the integrity of New Zealand's certification system. New Zealand notes that this audit schedule is greater than that required in any of AFFA's completed draft IRAs (apples from Japan, Korean pear, Ya pear from China, Philippine mangoes, durian from Thailand) which require at most a single audit visit plus a specialist visit in the first year of trade. New Zealand believes this is an unjustifiable discrimination.
The prescriptive nature of the audit programme also prevents the audit schedule or scope being modified in future years on the basis of audit history (as is normal practice when auditing quality systems).
| New Zealand requests that AFFA review the requirement for two full audits of MAF systems so that it is consistent with requirements for other countries. |
4.1.2.9 Strategy 11 - On-arrival inspection
The on-arrival inspection procedures have the potential to restrict trade by causing unjustifiable delays on cargo clearance. AFFA requires that fruit with any sign of damage, rot or punctures would be examined internally and action taken if E. amylovora infection is confirmed. It is not clear how AFFA proposes that E. amylovora infections be confirmed (or otherwise), however if this requires laboratory testing for E. amylovora there is potential for any consignment with even the slightest damage to a single fruit to be delayed for several days. The risk of such damage harbouring E. amylovora is exceedingly small and the likelihood of detection is close to zero (refer section 4.1.2.5). New Zealand believes that this risk management option is not the least trade restrictive measure available to AFFA. A number of other measures have already been proposed by AFFA and New Zealand suggests that this additional measure adds negligible phytosanitary security and is potentially very trade restrictive.
As is outlined in section 4.1.2.5, expert opinion contends that endophytic E. amylovora can not be detected by phytosanitary inspection.
| New Zealand considers that on-arrival inspection for endophytic E. amylovora does not add to phytosanitary security and is potentially very trade restrictive. |
4.1.3 Epiphytic contamination of fruit surfaces
AFFA has proposed five measures to reduce the risk of epiphytic contamination of fruit surfaces, however in the risk assessment there is no consideration of the risk posed by epiphytic contamination of the fruit surface (other than the calyx). Some data has been presented indicating that E. amylovora is sensitive to ultraviolet light, and as such would not survive on the unprotected fruit surface. Given the rarity of fruit surface contamination and the exceedingly low risk of such contamination leading to the establishment of fire blight in Australia, it is doubtful whether any measures are justified to further reduce this risk.
New Zealand suggests that passing fruit through a water dump (an existing pack house practice) would reduce the risk of surface contamination and would be less trade restrictive that the measures proposed by AFFA.
| New Zealand requests that AFFA consider that a water dump is an alternative, less trade restrictive measure. |
4.1.3.1 Strategy 1 - Establishment of registered blocks (REBs) free from fire blight disease
Most researchers have been unable to isolate E. amylovora from the surface of mature apple fruit from orchards free of fire blight symptoms. The timing of these inspections varies, from blossom, blossom plus fruitlet, to harvest inspections with very little difference in the resulting inability to recover bacteria. A single inspection to ensure an orchard block is free from fire blight (which may also be required to reduce the risk of calyx infestation and endophytic infection) would also reduce the risk of surface contamination without the need for 6 inspections over two seasons.
| New Zealand believes that, to further reduce the possibility of surface contamination, a single inspection at blossom or fruitlet would be sufficient. |
4.1.3.2 Strategy 2 - Establishment of detection zones
It is difficult to understand the justification for a 50 m detection zone. Surface contamination of fruit would most likely be caused by short range dispersal from infected trees through rain splash, rather than long distance spread. It has been suggested that the buffer zone serves as a barrier to prevent rain splash being blown into an export block. Presumably this measure is designed to protect the export blocks from becoming infected with fire blight, rather than fruit surfaces being contaminated.
| New Zealand requests that AFFA document the rationale for a 50 m detection zone to prevent fruit surfaces being contaminated. |
4.1.3.3 Strategy 3 - Disinfestation of harvesting bins
This appears to be a measure that would possibly reduce in some small way an already incredibly small risk - i.e., that of fruit surfaces becoming contaminated. If fruit are passed through a water dump (or chlorine dip as proposed by AFFA) this and the previous measure are redundant.
| New Zealand considers disinfestation of harvesting bins to be of no value in reducing the risk of surface infestation. |
4.1.3.4 Strategy 4 - Disinfestation of fruit
As discussed in 3.1.1.2 (ii) all fruit passes through a water dump to convey it to the packing line. In developing the chlorine treatment it was found that a simple wash is almost as effective. New Zealand proposes that this measure be considered as a means of reducing the already extremely low risk posed by surface contaminated fruit.
If this chlorine treatment measure is required by AFFA, then the other measures including sourcing fruit from orchards free from fire blight with buffer zones, and disinfestation of harvest bins are clearly not necessary. The chlorine dip is a one-off treatment for surface contamination and needs no other measures to support it.
One issue that AFFA may wish to consider before requiring compulsory surface disinfestation of fruit is the possibility that this treatment may in fact increase the risk of the development of endophytic infections (as discussed in section 3.1.1.1 (iii)).
| New Zealand requests that AFFA reviews the requirement and justification for chlorine dipping. |
4.1.4 The presence of trash with imported fruit
AFFA has identified the possibility that trash infected with E. amylovora may be associated with apple fruit but the probability of this occurring has not been assessed. Despite this, AFFA believes that 6 phytosanitary measures or procedures are required to manage this perceived risk. New Zealand accepts that infected plant material is a potential risk (although there are no demonstrated vectors or means of transfer), and accept that a phytosanitary requirement that fruit is free from trash (as confirmed by phytosanitary inspection) is a reasonable measure.
| New Zealand accepts that the requirement for fruit to be free from trash is a reasonable measure, but questions the necessity for further measures such as chlorine dipping and asks AFFA to demonstrate how such measures reduce risk. |
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