New data on quarantine pests and pests of the EPPO Alert List
By searching through the literature, the EPPO Secretariat has extracted the following new data concerning quarantine pests and pests included (or formerly included) on the EPPO Alert List, and indicated in bold the situation of the pest concerned using the terms of ISPM no. 8.
- New records
During summer 2016, symptoms of plant stunting and leaf chlorosis were observed in 2 sunflower fields (Helianthus annuus) in Fuentes de Andalucia (Spain) and Serpa (Portugal). Studies confirmed the presence of the highly virulent race 705 of Plasmopara halstedii (EU Annexes) in these 2 fields. Downy mildew of sunflower is frequently observed in Spain (although it is the first time that race 705 is found there), but this is the first time that the disease is reported from Portugal (García-Carneros and Molinero-Ruiz, 2017). Present, few records (one field in Serpa).
In Australia, Dickeya dianthicola (EPPO A2 List) was initially detected in seed potato (Solanum tuberosum) crops in Dandaragan and Myalup (Western Australia) in June 2017. Further studies detected the bacterium in dahlia tubers in Albany, Western Australia. Eradication of D. dianthicola from Australia is not considered technically feasible (IPPC, 2017). Present: only in some areas.
In Morocco, Dickeya dianthicola (EPPO A2 List) has recently been detected for the first time on potato (Solanum tuberosum). In March 2016, blackleg symptoms were observed in commercial potato fields in the north of Morocco. The identity of the bacterium was confirmed using molecular tools (PCR, sequencing, pathogenicity tests to verify Koch’s postulates) (Oulghazi et al., 2017). Present, only in some areas (Northern Morocco).
Drosophila suzukii (Diptera: Drosophilidae – EPPO A2 List) has recently been detected in French Polynesia. The first specimens were collected by a scientist (on holiday) in Moorea in January 2017. The identity of the pest was confirmed by the Australia Museum Research Institute in February 2017. The pest was then also found in Tahiti. The pest occurs at low prevalence and no damage has been recorded in fruit orchards (IPPC, 2017). Present: at low prevalence.
- Detailed records
In Croatia, the occurrence of ‘Candidatus Phytoplasma mali’ (EPPO A2 List) which was previously suspected on the basis of symptoms, has now been confirmed by molecular tests. During a survey conducted from 2011 to 2014, the pathogen was detected in apple trees (Malus domestica) and psyllid vectors (Cacopsylla picta) (Križanac et al., 2017).
Ditylenchus destructor (EU Annexes) occurs in Inner Mongolia, China. In July 2016, lesions were observed on potatoes (Solanum tuberosum) collected from Hohhot. Laboratory studies (morphology, molecular and pathogenicity tests) confirmed the identity of the nematode. The infested field has been subjected to strict quarantine measures to prevent any further spread (Ou et al., 2017).
In the Republic of Korea, Erwinia amylovora (EPPO A2 List) was confirmed by using molecular techniques in 18 pear orchards and 4 apple orchards, as of August 2017. These orchards are located within an area of 16 km diameter in Anseong and Cheonan. Eradication continues (IPPC, 2017). The pest status of Erwinia amylovora in the Republic of Korea is officially declared as: Transient: actionable, under eradication.
In Canada, Halyomorpha halys (Hemiptera: Pentatomidae – formerly EPPO Alert List) was first detected in 2012 in Hamilton, Ontario. Its presence was then reported in Alberta and Québec. In British Columbia, it was first detected in 2015. In this province and as of October 2017, H. halys occurs at low levels in urban areas of Fraser Valley and Vancouver, Brentwood Bay on Vancouver Island and the Okanagan Valley (INTERNET, 2017).
Leptoglossus occidentalis (Hemiptera: Coreidae) is reported for the first time from the island of Crete (GR). The first specimen was observed in 2015-08-21 in Ferma, in the Southeastern coastal part of the island (van der Heyden, 2017).
- Host plants
In Taiwan, symptoms of brownish necrotic spots surrounded by a yellowish halo were observed for the first time on leaves of Citrus depressa in Chiayi city in 2015 and 2016. Laboratory studies confirmed the presence of Xanthomonas citri subsp. citri (EPPO A1 List) pathotype A in symptomatic samples. This is the first time that C. depressa is reported as a natural host of X. citri subsp. citri (Huang and Ni, 2017).
Sources
García-Carneros AB, Molinero-Ruiz L (2017) First report of the highly virulent race 705 of Plasmopara halstedii (downy mildew of sunflower) in Portugal and in Spain. Plant Disease 101(8), p 1555.
Huang CJ, Ni HF (2017) First report of Citrus depressa as a new natural host of Xanthomonas citri subsp. citri pathotype A in Taiwan. Journal of Plant Pathology 99(1), p 289.
INTERNET
British Columbia. Brown Marmorated Stink Bug (BMSB) Pest Alert. https://www2.gov.bc.ca/gov/content/industry/agriculture-seafood/animals-and-crops/plant-health/insects-and-plant-diseases/tree-fruits/brown-marmorated-stink-bug
IPPC website
- Australia (AUS-86/2 of 2017-08) Dickeya dianthicola in Western Australia. https://www.ippc.int/en/countries/australia/pestreports/2017/11/dickeya-dianthicola-in-western-australia/
– French Polynesia (PYF-10/2 of 2017-07-12) Drosophila suzukii présent à Tahiti & Moorea. https://www.ippc.int/en/countries/french-polynesia/pestreports/2017/07/drosophila-suzukii-present-a-tahiti-moorea/
- Republic of Korea (KOR-05/2 of 2017-08-24) Report of outbreak of Erwinia amylovora in Rep. of Korea in 2017. https://www.ippc.int/en/countries/republic-of-korea/pestreports/2017/08/report-of-outbreak-of-erwinia-amylovora-in-rep-of-korea-in-2017/
Križanac I, Plavec J, Budinšćak Ž, Ivić D, Škorić D, Šegura Musić M (2017) Apple proliferation disease in Croatian orchards: a molecular characterization of 'Candidatus Phytoplasma mali'. Journal of Plant Pathology 99(1), 95-101.
Ou SQ, Wang YW, Peng DL, Qiu H, Bai QR, Shi SS (2017) Discovery of potato rot nematode, Ditylenchus destructor, infesting potato in Inner Mongolia, China. Plant Disease 101(8), p 1554.
Oulghazi S, Khayi S, Lafkih N, Massaoudi Y, El Karkouri A, El Hassouni M, Faure D, Moumni M (2017) First report of Dickeya dianthicola causing blackleg disease on potato in Morocco. Plant Disease 101(9), 1671-1672.
van der Heyden T (2017) Leptoglossus occidentalis Heidemann, 1910 (Hemiptera: Heteroptera: Coreidae: Coreinae: Anisoscelini) has reached the Greek island of Crete. Arquivos Entomolóxicos 18, 185-187.