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In 2005, rose plants ( Rosa rugosa cv. ‘Plena’) exhibiting typical phytoplasma disease symptoms of stunting, yellowing, witches’-broom and dieback were observed in Pingyin, Shandong Province, China. The disease, rose witches’-broom (RoWB), is progressively destructive and can be graft-transmitted. Polymerase chain reaction (PCR), sequencing of PCR products and electron microscopy were used to investigate the possible association of phytoplasma with RoWB. All results indicated that presence of phytoplasma in the symptomatic rose plants. Sequence alignment of 16S rRNA gene, tuf gene and rp gene confirmed that the phytoplasma associated with RoWB is the causal agent of Paulownia witches’-broom disease, which might be transmitted from the paulownia tree that is several meters away. To our knowledge, this is the first report of the molecular characterization of phytoplasma infecting rose in China. [ABSTRACT FROM AUTHOR]

The article discusses the Beet mosaic virus (BtMV) which infects vegetables, particularly lettuce (Lactuca sativa) in China. Accordingly, BtMV is widespread and mainly infects the plants belonging to the Chenopodiaceae, Solanaceae and Fabaceae. In 2004 and 2006, a series of field surveys were conducted to investigate such virus in Shandong Province, China. It mentions that lactuca sativa has shown symptoms of mosaic, puckering and severe stunting with an incidence of 30-40 %. Several tests were conducted and results indicate that the virus is BtMV.