Capsicum annuum - a new host of Parietaria mottle virus in Spain

D. Janssen¹*, E. Saez², E. Segundo¹, G. Martín¹, F. Gil¹ and I.M. Cuadrado¹

¹ CIFA-Almería, IFAPA, Autovia del Mediterraneo km 420, 04745 La Mojonera, Spain
² Laboratorio de Sanidad Vegetal, Consejería de Agricultura y Pesca, Autovia del Mediterraneo km 420, 04745 La Mojonera, Spain

*dirkjanssen@telefonica.net

Accepted for publication 04/01/05

During the summer of 2004, bell pepper (Capsicum annuum) plants grown in a commercial greenhouse in Almeria (Southeast Spain) showed necrotic stems and fruit with brown patches and corky rings on the surface. Mechanical inoculation of sap from the fruits produced necrotic etching on leaves of Nicotiana tabacum cv. Xanthi, consistent with symptoms produced by members of the genus Ilarvirus (Fig. 1). Mechanical transmission from infected N. tabacum to 1-month-old bell pepper seedlings produced symptoms on stems and fruit, similar to those originally observed on the field plants (Fig. 2). 

Figure 1: Necrotic etching on leaves of Nicotiana tabacum cv. Xanthi infected with PMoV	Figure 2: Symptoms on the fruit of bell pepper infected with PMoV

Using total RNA extracts from diseased pepper and Nicotiana plants, RT-PCR analysis using specific primers for Parietaria mottle virus (PMoV) based on Genbank Accession No. AY496068 sequence (forward primer 5’-GATGTTGCCGCCGACGATTCTA-3’ and reverse primer 5’-TTTTCCCACAACCCGCAACAC-3’) produced an amplicon of the expected size (475 bp). Individual amplicons were cloned in E. coli, sequenced and analysed using Blastx analysis (NCBI, Bethesda, USA). All clones had an identical nucleotide sequence (Accession No. AY819660) and showed the highest percentage identity with the P1 gene for the replicase of Parietaria mottle virus (92% nucleotide and 97% amino acid). Following mechanical inoculation, the virus from pepper systemically-infected N. tabacum cv. Xanthi, N. tabacum cv. White Burley, N. glutinosa and Lycopersicon esculentum, as confirmed by RT-PCR testing. No infection was obtained in Chenopodium amaranticolor, C. quinoa, Solanum melongena, Datura stramonium and Cucumis sativus. The pepper isolate of PMoV was negative in ELISA when analysed with commercial antisera to Tomato spotted wilt virus, Cucumber mosaic virus, Tomato mosaic virus, Alfalfa mosaic virus, Pepper mild mottle virus, Tomato bushy stunt virus, Tobacco necrosis virus, Tobacco mild green mosaic virus and potyvirus. PMoV has been isolated from tomato crops in Italy, France, Greece and Spain (Ramasso et al., 1997; Marchoux et al., 1999; Roggero et al., 2000; Aramburu, 2001). This is the first report of a PMoV isolate with a distinct genome sequence and host range, capable of producing disease in pepper.

Acknowledgements

This work was supported with project PIA 03/31 from the Junta de Andalucía (Spain).

References

Aramburu J, 2001. First report of Parietaria mottle virus on tomato in Spain. Plant Disease 85, 1210.

Marchoux G, Parrella G, Gebre-Selassie K, Gagnalon P, 1999. Identification de deux Ilarvirus sur tomate dans le Sud de la France. Phytoma 522, 53-55.

Ramasso E, Roggero P, Dellavalle G, Lisa V, 1997. Necrosi apicale del pomodoro causata da un Ilarvirus. Informatore Fitopatologico 1, 71-77.

Roggero P, Ciuffo M, Katis N, Alioto D, Crescenzi A, Parrella G, Gallitelli D, 2000. Necrotic disease in tomatoes in Greece and southern Italy caused by the tomato strain of Parietaria mottle virus. Journal of Plant Pathology 82, 159.

The British Society for Plant Pathology