Risk assessment of Citripestis sagittiferella for the EU

Abstract

Following a request from the European Commission, the EFSA Panel on Plant Health performed a risk assessment of Citripestis sagittiferella (Lepidoptera: Pyralidae), the citrus pulp borer, an oligophagous pest reported from South-East Asia and restricted to Citrus spp. The entry risk assessment focused on the citrus fruit pathway. Two scenarios were considered: scenario A0 (current practice) and A2 (additional post-harvest cold treatment). Based on the outputs of the entry model obtained in scenario A0, the median number of founder populations in the EU citrus-growing area is estimated to be slightly less than 10 per year (90%-uncertainty interval between about one entry per 180 years and 1,300 entries per year). The risk of entry and the simulated numbers of founder populations are orders of magnitude lower for scenario A2 compared to scenario A0. The key uncertainties in the entry model include transfer, the cold treatment effectiveness, the disaggregation factor and sorting. The simulated numbers of established populations are only slightly lower than the numbers of founder populations. As the probability of establishment has little impact on the number of established populations, it is not a major source of uncertainty, despite the lack of data on the thermal biology of the pest. The median lag period between establishment and spread is estimated to be slightly more than 1 year (90%uncertainty interval between about 2 months and 33 months). After the lag period, the median spread rate by natural means (flying) and due to transport of harvested citrus fruit from orchards to packinghouses is estimated at about 100 km/year (90%-uncertainty interval between about 40 and 500 km/year). The main sources of uncertainties affecting the spread rate include the extent to which environmental factors could hamper the build-up of the populations and the lack of data on the spread rate at the origin. The median impact of C. sagittiferella in the EU citrus-growing area is estimated at about 10% of infested fruits among the harvested citrus fruits (90%-uncertainty interval between about 2% and 25%). Uncertainties affecting the impact assessment include the susceptibility of different Citrus species and cultivars.

Risk assessment of Resseliella citrifrugis for the EU

“…At the same time, the pest is less easy to detect compared to C. sagittiferella . However, there can be hundreds of larvae of R. citrifrugis per fruit, an order of magnitude higher than what was reported for C. sagittiferella (EFSA PLH Panel, 2023 ).…”

“…Note that one of the input parameters is a disaggregation of consignments factor (d) used to disaggregate the infested material entering into the EU to different locations in the risk assessment area, as in previous Panel PRAs (EFSA PLH Panel, 2017 , 2022 , 2023 ). For example, for d = 1, one ton of citrus fruit is delivered to one location, whereas if d = 2, one ton of citrus fruit is delivered to two locations (in consignments of 500 kg each).…”

“…The main uncertainties are described, and an assessment of the overall uncertainty and of the dependencies among parameters is included. In the EKEs for R. citrifrugis , the PRA on the citrus fruit borer, Citripestis sagittiferella (Moore) (Lepidoptera: Pyralidae) (EFSA PLH Panel, 2023 ) was used in a comparative approach by the panel of experts.…”

“…Following the comparative approach described above (Section 3 ), for the 1% value, it was considered that the pest is not a strong flyer as the moth C. sagittiferella (EFSA PLH Panel, 2023 ), so it could take more time for the foci to expand and uniformly infest orchards as C. sagittiferella could do. Also, C. sagittiferella is a tropical pest breeding all year round, whereas R. citrifrugis is a temperate pest with an overwintering period, thus probably relatively less aggressive.…”

“…Pomelo is seldom grown commercially in the EU, so the growing import of fruit of this Citrus species from China is likely to carry on over the next years. Indeed, it seems pomelo is becoming more and more popular in the EU and this trend is likely to continue in the future (EFSA PLH Panel, 2023 ). For all these reasons, the upper bounds of the confidence and prediction intervals of the regression appear as relevant references for the elicitation.…”