EFSA Journal (Apr 2024)
Pest risk assessment of African Leucinodes species for the European Union
Abstract
Abstract Following a request from the European Commission, the EFSA Panel on Plant Health performed a quantitative risk assessment for the EU of African Leucinodes species (Lepidoptera: Crambidae), which are fruit and shoot borers, especially of eggplant type fruit. The assessment focused on (i) potential pathways for entry, (ii) distribution of infested imports within EU, (iii) climatic conditions favouring establishment, (iv) spread and (v) impact. Options for risk reduction are discussed, but their effectiveness was not quantified. Leucinodes spp. are widely distributed across sub‐Saharan Africa but are little studied and they could be much more widespread in Africa than reported. Much African literature erroneously reports them as Leucinodes orbonalis which is restricted to Asia. The import of eggplant type fruit from sub‐Saharan Africa consists of special fruit types and caters mostly to niche markets in the EU. The main pathway for entry is fruit of Solanum aethiopicum and exotic varieties of eggplant (S. melongena). CLIMEX modelling was used with two possible thresholds of ecoclimatic index (EI) to assess establishment potential. Climates favouring establishment occur mostly in southern Europe, where, based on human population, 14% of the imported produce is distributed across NUTS2 regions where EI ≥ 30; or where 23% of the produce is distributed where EI ≥ 15. Over the next 5 years, an annual median estimate of ~ 8600 fruits, originating from Africa, and infested with African Leucinodes spp. are expected to enter EU NUTS2 regions where EI ≥ 15 (90% CR ~ 570–52,700); this drops to ~ 5200 (90% CR ~ 350–32,100) in NUTS2 regions where EI ≥ 30. Escape of adult moths occurs mostly from consumer waste; considering uncertainties in pathway transfer, such as adult emergence, mate finding and survival of progeny, the annual median probability of a mated female establishing a founder population in NUTS regions where EI ≥ 15 was estimated to be 0.0078 (90% CR 0.00023–0.12125). This equates to a median estimate of one founder population ~ every 128 years (90% CR approximately one every 8–4280 years). Using an EI ≥ 30, the median number of founder populations establishing in the EU annually is 0.0048 (90% CR 0.0001–0.0739), equating to a median estimate of one founder population approximately every 210 years (90% CR approximately one every 14–7020 years). Under climate change for the period 2040–2059, the percent of infested produce going to suitable areas would be increased to 33% for EI ≥ 15 and to 21% for EI ≥ 30. Accordingly, the waiting time until the next founder population would be reduced to median estimates of 89 years for EI ≥ 15 (90% CR ~ 6–2980 years) and 139 years for EI ≥ 30 (90% CR 9–4655 years). If a founder population were to establish, it is estimated to spread at a rate of 0.65–7.0 km per year after a lag phase of 5–92 years. Leucinodes spp. are estimated to reduce eggplant yield by a median value of 4.5% (90% CR 0.67%–13%) if growers take no specific action, or 0.54% (90% CR between 0.13% and 1.9%) if they do take targeted action, matching previous estimates made during a risk assessment of L. orbonalis from Asia.
Keywords
