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 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 May 2013, symptoms resembling those of bacterial leaf blight were observed on wild rice (Oryza longistaminata) near Tanguiéta town, Northwest Benin. Laboratory analysis confirmed the presence of Xanthomonas oryzae pv. oryzae (EPPO A1 List) in diseased plants. In July and in November 2013, further samples were collected from wild rice (O. longistaminata) and also from other host plants including rice (O. sativa and O. glaberrima) around the site where the first finding was made. All samples collected in July were negative in multiplex PCR assays, whereas those collected in November from wild rice (O. longistaminata) gave positive results. It is concluded that further studies are needed to evaluate the importance of the disease in Benin (Afolabi et al., 2016). Present, first found in 2013 near Tanguiéta town on wild rice.
In March 2014, Ophelimus maskelli (Hymenoptera: Eulophidae) was found in Southern California, USA. This invasive pest of eucalyptus was observed in the campus of the University of California Riverside (Riverside county). Since then, O. maskelli has also been found in San Diego and Orange counties. This is the first time that this pest is reported from the USA and from the Americas (Burks et al., 2015). Present, first found in 2014 in Southern California.
In Mexico, during a survey for viral diseases conducted from 2008 to 2012 in commercial peach orchards, Prunus necrotic ringspot virus (PNRSV) was detected. All tested samples showed viral symptoms (yellow mottle, chlorotic ringspot, linear patterns, and mosaic), but only 80% of them were positive for PNRSV, suggesting the presence of other pathogens. New samples consisting of young shoot tips and leaves were collected from symptomatic peach trees during summers 2013 and 2014 in the municipalities of Tepatlaxco, San Juan Coronango, and Santa Rita Tlahuapan (state of Puebla); Tlacotepec and Tetela del Volcán (state of Morelos); and Texcoco and Temazcaltepec (state of México). The PNRSV negative samples were tested (molecular hybridization) for the presence of Peach latent mosaic viroid (PLMVd) and Hop stunt viroid (HSVd). Results confirmed the presence of PLMVd in some plants from all municipalities. HSVd was not detected. This is the first confirmed report of PLMVd in Mexico (De La Torre-Almaráz et al., 2015). Present, found in samples collected from the states of Puebla, Morelos and México.
- Detailed records
In Italy, Hymenoscyphus fraxineus (formerly Alert List) has been reported on Fraxinus excelsior since 2010 in the northern part of the peninsula, close to the Alps. In July 2015, symptomatic trees of F. excelsior were observed in Montepiano (province of Prato), in Toscana. Laboratory analysis (morphological, molecular methods) confirmed the presence of H. fraxineus in diseased trees. This is the first time that H. fraxineus is reported from central Italy in the Apennines, representing the southernmost limit of the currently known distribution of the fungus in Europe (Luchi et al., 2016).
Drosophila suzukii (Diptera: Drosophilidae – EPPO A2 List) occurs in the state of Paraná, Brazil. The first specimens were recovered from fruits (Eugenia involucrata, Eriobotrya japonica, Prunus persica) collected in 2014 in the municipalities of Porto Vitória and União da Vitória. This is also the first time that Eugenia involucrata and Eriobotrya japonica are recorded as host plants for D. suzukii (Santos Geisler et al., 2015).
- Diagnostics
A new RT-LAMP assay has been developed for the detection of Tomato chlorosis virus (Crinivirus, ToCV – EPPO A2 List) either in total RNA or crude RNA extracted from infected plants. This method can also be used to detect ToCV from purified RNA extracted from its whitefly vector (Bemisia tabaci). This new RT-LAMP assay was found to be a rapid, sensitive, and specific tool for the surveillance and management programmes of ToCV (Karwitha et al., 2015).
- New host plants
Tomato spotted wilt virus (Tospovirus – EPPO A2 List) has been detected in a leaf sample of Pittosporum tobira showing symptoms of chlorotic ring spots and line patterns which was collected in Virginia, USA (Liu et al., 2016).
Studies carried out in Italy have shown that Urtica membranacea (Urticaceae) is a host for Tomato yellow leaf curl virus and Tomato yellow leaf curl Sardinia virus (both Geminivirus, EPPO A2 List). Affected U. membranacea plants showed symptoms of leaf yellowing and curling. These weeds were growing along the rows of a greenhouse tomato crop affected by tomato yellow leaf curl disease and Bemisia tabaci (Parella et al., 2016).
Sources
Afolabi O, Amoussa R, Bilé M, Oludare A, Gbogbo V, Poulin L, Koebnik R, Szurek B, Silué D (2016) First report of bacterial leaf blight of rice caused by Xanthomonas oryzae pv. oryzae in Benin. Plant Disease 100(2), p 515.
Burks RA, Mottern JL, Waterworth R, Paine TD (2015) First report of the Eucalyptus gall wasp, Ophelimus maskelli (Hymenoptera: Eulophidae), an invasive pest on Eucalyptus, from the Western Hemisphere. Zootaxa 3923(3), 448-450. http://biotaxa.org/Zootaxa/article/view/zootaxa.3926.3.10
De La Torre-Almaráz, R, Pallás V, Sánchez-Navarro JA (2015) First report of Peach latent mosaic viroid in peach trees From Mexico. Plant Disease 99(6), p 899.
Karwitha M, Feng ZK, Shen Y, Essendi W, Zhang WN, Li JY, Tao XR (2016) Rapid detection of Tomato chlorosis virus from infected plant and whitefly by one-step reverse transcription loop-mediated isothermal amplification. Journal of Phytopathology 164(4), 217-290.
Liu H, Tolin S, Bush E, Creswell T, Hansen MA, Wang X (2016) First report of Tomato spotted wilt virus on Pittosporum tobira in the United States. Plant Disease 100(2), p 538.
Luchi N, Ghelardini L, Santini A, Migliorini D, Capretti P (2016) First record of ash dieback caused by Hymenoscyphus fraxineus on Fraxinus excelsior in the Apennines (Tuscany, Italy). Plant Disease 100(2), p 535.
Parrella G, Nappo AG, Giorgini M, Stinca A (2016) Urtica membranacea: a new host for Tomato yellow leaf curl virus and Tomato yellow leaf curl Sardinia virus in Italy. Plant Disease 100(2), p 539.
Santos Geisler FC, Santos J, Holdefer DR, Mello Garcia FR (2015) [First record of Drosophila suzukii (Matsumura, 1931) (Diptera: Drosophilidae) for the State of Paraná, Brazil and new hosts]. Revista de Ciências Ambientais, Canoas 9(2), 125-129 (in Portuguese). http://dx.doi.org/10.18316/1981-8858.15