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
In Zambia, Curtobacterium flaccumfaciens pv. flaccumfaciens (EPPO A2 List) was found for the first time in March 2019. The bacterium was detected in symptomatic soybean (Glycine max) plants grown in research plots in Kabwe and Mpogwe (Pawlowski and Hartman, 2019). Present.
In South Korea, field surveys were conducted in major production areas for strawberry in 2018-2019 to determine the incidence of aphid-transmitted viruses. Strawberry mild yellow edge virus (SMYEV – EU Annexes), Strawberry mottle virus (SMoV – EU Annexes) were detected with low infection rates of 0.7% and 1.3%, respectively. Strawberry crinkle virus (SCV – EU Annexes), and Strawberry vein banding virus (SVBV – EPPO A2 List) were not detected. No obvious symptoms were observed in the strawberry plants infected by SMYEV or SMoV (Kwon et al., 2019). SMYEV and SMoV: Present.
- Detailed records
Apple stem grooving virus and apple chlorotic leaf spot virus (both listed on EU Annexes) were first found infecting loquat (Eriobotrya japonica) in Chongqing, China in March 2018. This is the first report of these viruses naturally infecting loquat (Liu et al., 2019).
- Eradication
In May 2020, Ralstonia solanacearum race 3 biovar 2 (EPPO A2 List) was detected in Pelargonium in Canada (EPPO RS 2020/098). The bacterium was found in a greenhouse in Ontario. An eradication campaign was implemented and involved more than 88 facilities in 8 provinces. In July 2020, the Canadian Food Inspection Agency announced that Ralstonia solanacearum race 3 biovar 2 had been successfully eradicated from Canadian greenhouses.
The pest status of Ralstonia solanacearum race 3 biovar 2 in Canada is officially declared as: Absent, pest eradicated.
In April 2020, Ralstonia solanacearum race 3 biovar 2 (EPPO A2 List) was detected on greenhouse Pelargonium in the USA (EPPO RS 2020/099). The bacterium was first found in a greenhouse in Michigan and then in another site. An eradication campaign was initiated, involving more than 650 facilities in 44 states, and in June 2020 USDA-APHIS announced that Ralstonia solanacearum race 3 biovar 2 had been successfully eradicated from US greenhouses.
The pest status of Ralstonia solanacearum race 3 biovar 2 in the USA is officially declared as: Absent and eradicated from the United States.
- Host plants
Tomato chlorosis virus (Crinivirus, ToCV – EPPO A2 List) has been detected in seedlings of Tectona grandis (Lamiaceae) in Brazil. Affected plants were showing interveinal yellowing and were also infested by Bemisia tabaci (Borges et al., 2019).
- New pests
Phytophthora abietivora is a new species in the genus Phytophthora, described from diseased Christmas trees (Abies fraseri) in Connecticut (USA). The pathogen caused root rots leading to death of A. fraseri trees (Li et al., 2019).
- Epidemiology
Studies conducted in the Republic of Korea had shown that infected seeds of tomato (Solanum lycopersicum) could transmit Tomato yellow leaf curl virus (TYLCV - EPPO A2 List) (EPPO RS 2018/173). However, further surveys conducted by Pérez-Padilla et al. (2019) with the type strain (TYLCV-IL) on more than 3000 plants of seven tomato genotypes concluded that most of the virus is located externally, as contaminant of the seed coat and that TYLCV-IL is not seed transmitted in tomato.
Sources
Borges RCF, Fontes MG, Macedo MA, Lima F, Boiteux LS, Fonseca MEN (2019) First report of tomato chlorosis virus infecting Tectona grandis associated with infestation of Bemisia tabaci Mediterranean in Central Brazil. Plant Disease 103(10), 2704-2705.
Kwon S-J, Yoon J-B, Cho I-S, Yoon J-Y, Kwon T-R (2019) Incidence of aphid-transmitted strawberry viruses in Korea and phylogenetic analysis of Korean isolates of strawberry mottle virus. Research in Plant Disease 25(4), 226–232 (in Korean with English abstract) https://doi.org/10.5423/RPD.2019.25.4.226
Li D-W, Schultes NP, LaMondia JA, Cowles RS (2019) Phytophthora abietivora, a new species isolated from diseased Christmas trees in Connecticut, USA. Plant Disease 103(12), 3057-3064. https://doi.org/10.1094/PDIS-03-19-0583-RE
Liu Q, Xuan Z, Wu J, Qiu Y, Li M, Zhang S, Wu D, Li R, Cao M (2019) Loquat is a new natural host of apple stem grooving virus and apple chlorotic leaf spot virus in China. Plant Disease 103(12), p 3290. https://doi.org/10.1094/PDIS-04-19-0721-PDN
NAPPO Phytosanitary Alert System. Official Pest Reports.
- Canada (2020-07-20) Ralstonia solanacearum, race 3 biovar 2 (Rs R3bv2) eradicated from Canadian greenhouses. https://www.pestalerts.org/official-pest-report/ralstonia-solanacearum-race-3-biovar-2-rs-r3bv2-eradicated-canadian
- USA (2020-06-23) Ralstonia solanacearum race 3 biovar 2: eradicated from US greenhouses. https://www.pestalerts.org/official-pest-report/ralstonia-solanacearum-race-3-biovar-2-eradicated-u-s-greenhouses
Pawlowski ML, Hartman GL (2020) First report of Curtobacterium flaccumfaciens pv. flaccumfaciens causing bacterial tan spot on soybean in Africa. Plant Disease 103(10), p 2665. https://doi.org/10.1094/PDIS-05-19-1036-PDN
Pérez-Padilla V, Fortes IM, Romero-Rodríguez B, Arroyo-Mateos M, Castillo AG, Moyano C, De León L, Moriones E (2020) Revisiting seed transmission of the type strain of Tomato yellow leaf curl virus in tomato plants. Phytopathology 110(1), 121-129.