New data on quarantine pests and pests of the EPPO Alert List
By browsing through the literature, the EPPO Secretariat has extracted the following new data concerning quarantine pests and pests included on the EPPO Alert List. The situation of the pest concerned is indicated in bold, using the terms of ISPM no. 8.
- New records
Euphorbia mosaic virus (Begomovirus - EU Annexes) occurs in Nicaragua. This virus was detected on the weed species, Euphorbia heterophylla (Ala-Poikela et al., 2005). Present, no detail.
During a survey in Bolivia, symptoms of peach yellow leaf roll were observed in a peach orchard at San Isidro, in the province of Santa Cruz. Many trees were dead or dying. Leaf samples were collected from symptomatic and asymptomatic trees. Molecular studies (PCR, RFLP) revealed the presence of a phytoplasma which presented 98% similarity with ‘Candidatus Phytoplasma australiense’ (Jones et al., 2005). Present, no detail.
In Venezuela, during surveys on begomoviruses of tomato crops in 3 Andean states (Táchira, Mérida, Trujillo), Tomato mottle virus (EU Annexes) and Tomato yellow leaf curl virus (EPPO A2 list) were detected (Nava et al., 2006). Present, no detail.
- Detailed records
In 2006, Acizzia jamatonica (Homoptera: Psyllidae - formerly on the EPPO Alert List) was reported for the first time in Toscana, Italy. It was discovered on Albizia julibrissin in a nursery in the province of Pistoia (NPPO of Italy, 2006).
In China, studies on Citrus tristeza virus (Closterovirus, CTV – EPPO A2 list) were carried out in 2003-2004 in sweet orange (Citrus sinensis) orchards from 8 provinces. Symptoms observed varied from small fruit size and poor fruit quality to tree decline and death. Out of 192 samples collected and tested by DTBIA, 158 tested positive from all provinces: Chongqing*, Sichuan, Fujian, Hunan, Guangxi*, Yunnan*, Guangdong, Jiangxi* (Xu et al., 2006). The EPPO Secretariat had previously no data on the presence of CTV in the provinces marked with an asterisk.
In the USA, Cucurbit yellow stunting disorder virus (Crinivirus – EPPO A2 list) is reported for the first time from Arizona (NAPPO, 2006). It is also suspected that the virus occurs in California, but this has not been confirmed. Until this report, the virus had only been detected in Texas.
- New host plants
In 2005, Phakopsora pachyrhizi (EPPO Alert List) was observed on several Phaseolus crops (P. coccineus, P. lunatus and P. vulgaris) growing in the vicinity of infected soybean fields in Florida, USA (Lynch et al., 2006).
Phakopsora pachyrhizi (EPPO Alert List) was found on a weed, Desmodium tortuosum (Fabaceae) in Georgia, USA. This weed is widespread in southern USA and could serve as an overwintering source for P. pachyrhizi and a potential inoculum for soybean crops (Sconyers et al., 2006).
Sources
Ala-Poikela M, Svensson E, Rojas A, Horko T, Paulin L, Valkonen JPT, Kvarnheden A (2005) Genetic diversity and mixed infections of begomoviruses infecting tomato, pepper and cucurbit crops in Nicaragua. Plant Pathology 54(4), 448-459.
Jones P, Arocha Y, Antesana O, Montilliano E, Franco P (2005) First report of an isolate of ‘Candidatus Phytoplasma australiense’ associated with a yellow leaf roll disease of peach (Prunus persicae) in Bolivia. Plant Pathology 54(4), p 558.
Lynch TN, Marois JJ, Wright DL, Harmon PF, Harmon CL, Miles MR (2006) First report of soybean rust caused by Phakopsora pachyrhizi on Phaseolus spp. in the United States. Plant Disease 90(7), p 970.
NAPPO Pest Alert System (2006) First report of Cucurbit yellow stunting disorder virus in Arizona and possibly California (pending DNA confirmation). http://www.pestalert.org/viewNewsAlert_print.cfm?naid=30
Nava AR, Patte CP, Hiebert E, Polston JE (2006) Detection and variability of begomoviruses in tomato from the Andean states of Venezuela. Plant Disease 90(1), 61-66.
NPPO of Italy, 2006-09.
Sconyers LE, Kemerait RC Jr, Brock JH, Gitaitis RD, Sanders FH, Phillips DV, Jost PH (2006) First report of Phakopsora pachyrhizi, the causal agent of soybean rust, on beggarweed in the United States. Plant Disease 90(7), p 972.
Xu XF, Zhou CY, Song Z, Yang FY (2006) Preliminary studies on CPG/Hinf I RFLP groups of Citrus tristeza virus infected sweet oranges in China. Agricultural Sciences in China 5(1), 39-44.