Final report for the non-regulated analysis of existing policy for table grapes from Sonora, Mexico

Harlequin ladybird

Harmonia axyridis (EP)

Harmonia axyridis was included in the final import policy for table grapes from China (Biosecurity Australia 2011a), from California to Western Australia (DAFF 2013) and from Japan (Department of Agriculture 2014). In these existing policies, the unrestricted risk estimate for H. axyridis was assessed as not achieving the ALOP for Australia and therefore specific risk management measures are required for this pest.

The likelihood of establishment and spread of H. axyridis in Australia for table grapes from Sonora is comparable to previous assessments. These likelihoods relate specifically to events that occur in Australia and are principally independent of the importation pathway. The consequences of H. axyridis are also independent of the importation pathway.

Harmonia axyridis has a wide host range and host material is likely to be available all year round in Australia. The likelihood of distribution for this pest for table grapes from Sonora is comparable to that for table grapes from the previously assessed export areas.

The department considered factors affecting the likelihood of importation for H. axyridis for table grapes from Sonora and those previously assessed. The likelihood of importation for H. axyridis for table grapes from Sonora is comparable to that in the previous assessments, particularly to that for table grapes from California to Western Australia (DAFF 2013).

In addition, the department has also reviewed the latest literature (for example Kenis et al. 2016; Roy & Brown 2015; Roy et al. 2016; Torres-Acosta & Sánchez-Peña 2015) and no new information is available that would significantly change the risk ratings for importation, distribution, establishment, spread and consequences as set out for H. axyridis in the existing policies.

1. Unrestricted risk estimate

The unrestricted risk estimate for H. axyridis for table grapes from Sonora is comparable to the estimates in previous assessments, and does not achieve the ALOP for Australia. Therefore, specific risk management measures are required for this pest.

2. Fruit flies

Anastrepha fraterculus and Ceratitis capitata (EP)

Anastrepha fraterculus (South American fruit fly) and Ceratitis capitata (Mediterranean fruit fly, Medfly) belong to the family Tephritidae. They have been grouped together because of their related biology and taxonomy, and are considered to pose a similar risk and to require similar mitigation measures.

Several fruit flies species were assessed previously in a number of existing import policies, for example, in the final import policy for truss tomatoes from the Netherlands (DAFF 2003), sweet oranges from Italy (Biosecurity Australia 2005a), mangoes from India (Biosecurity Australia 2008a), longan and lychee from China and Thailand (DAFF 2004) and table grapes from Chile (Biosecurity Australia 2005b) and from China (Biosecurity Australia 2011a). In these existing policies, the unrestricted risk estimate for fruit flies does not achieve the ALOP for Australia and therefore specific risk management measures are required for the pests.

Although the department acknowledges that Mexico has a national program for the control, eradication and suppression of fruit flies of economic importance in Sonora, Mexico, fruit fly outbreaks do occur from time to time in Mexico. For this reason, the department considers it necessary to include these fruit fly species as pests requiring specific risk management measures. Area freedom is included as one of the measure options for these fruit fly species.

1. Unrestricted risk estimate

The unrestricted risk estimate for fruit flies for table grapes from Sonora is comparable to the estimates in previous assessments, and does not achieve the ALOP for Australia. Therefore, specific risk management measures are required for these species.

3. Spotted wing drosophila

Drosophila suzukii (EP)

The quarantine risks posed by Drosophila suzukii from all countries and for all commodities, including table grapes, were previously assessed in the Final pest risk analysis (PRA) report for Drosophila suzukii (Department of Agriculture 2013). Therefore, there is no need to reassess this pest here. A summary of pest information from the final PRA report for D. suzukii is provided here.

In addition, the department has also reviewed the latest literature (for example Asplen et al. 2015; García-Ávila et al. 2016; Grant & Sial 2016) and no new information is available that would significantly change the risk ratings for importation, distribution, establishment, spread and consequences as set out in the final PRA report for D. suzukii.

Drosophila suzukii was reported in Mexico in 2011 (NAPPO 2011), and is now reported from the states of Aguascalientes, Baja California, Colima, Guanajuato, Jalisco, Michoacán, Estado de México, Querétaro and Veracruz (CABI 2014; García-Ávila et al. 2016; Lasa & Tadeo 2015). Drosophila suzukii is not reported from the state of Sonora and Mexico has domestic movement control in place to restrict the entry of pests, including D. suzukii, into Sonora.

Drosophila suzukii preferentially oviposit on ripe fruit but will also oviposit on unripe and overripe fruit (Asplen et al. 2015; Brewer et al. 2012; Kanzawa 1939; Lee et al. 2011). Larvae feeding on very acidic fruit fail to complete development (Kanzawa 1935). In its native and introduced range, D. suzukii has been recorded to cause damage to a range of commercial fruits including grapes, cherry, blueberry, red bayberry, strawberry and various caneberries.

On grapes, oviposition trials on wine and table grapes have shown that fully-ripe table grapes can be attacked (Atallah et al. 2014; Maiguashca et al. 2010; Saguez, Lasnier & Vincent 2013). Damaged fruit with low sugar levels will be oviposited in but larvae develop poorly and fail to pupate (Maiguashca et al. 2010). Kanzawa (1939) recorded that different grape varieties sustained different levels of attack and considered skin thickness was the factor that limited oviposition. Oviposition of D. suzukii has been reported on a number of grape varieties/cultivars which are 100 per cent V. vinifera, such as Gros Coleman, Muscat of Alexandra, Muscat of Hamburg, Foster’s seeding Rose de Italy, Kyoshin (Kanzawa 1939), Thompson Seedless (Lee et al. 2011), Black Manuka and Perlette (WSUE 2010). Reports of oviposition on grape varieties/cultivars which are 100 per cent Vitis labrusca have not been found. There have been reports of a number of grape varieties/cultivars not being attacked by D. suzukii, some of these are 100 per cent Vitis vinifera (for example Koshu, Chasselas de Fontainbleau, Golden champion and White Malaga), some are 100 per cent Vitis labrusca (for example Concord, Eaton, Niagara and Hostess seedling) (Kanzawa 1939), and some are hybrids between V. vinifera and V. labrusca for which percentage of V. vinifera as parentage range from 25 per cent (for example Early Campbell) (Maiguashca et al. 2010) to 75 per cent (for example Brighton) (Kanzawa 1939).

The risk scenario of concern for D. suzukii is the presence of the larvae in mature bunches of table grapes.

1. Unrestricted risk estimate

Based on the Final pest risk analysis (PRA) report for Drosophila suzukii (Department of Agriculture 2013) the unrestricted risk estimate for D. suzukii for table grapes from Sonora does not achieve the ALOP for Australia. Therefore, specific risk management measures are required for this pest.

4.