'Candidatus Phlomobacter fragariae' is the prevalent agent of marginal chlorosis of strawberry in French production fields and is transmitted by the planthopper Cixius wagneri (China).

摘要

A large scale survey for marginal chlorosis in French strawberry production fields and nurseries by PCR amplification of Candidatus Phlomobacter fragariae and stolbur phytoplasma 16S rDNA was conducted in 1996. Compilation of survey results from 1996 to 2001, clearly showed that Ca. P. fragariae is predominant in strawberry production fields, while the stolbur phytoplasma predominantly is detected in nurseries. In strawberry fruit production fields there were 2 transmission periods, one in spring, the other from late-summer to early-autumn. When looking for putative insect vectors during the 2001 and 2002 spring and autumn seasons in strawberry production fields affected by marginal chlorosis, the planthopper Cixius wagneri was captured. This insect was encountered very rarely in previous insect surveys conducted in spring and summer. High proportions of these planthoppers were shown to be infected by Ca. P. fragariae using the spoT PCR-RFLP detection method and sequencing. When caged on healthy, in vitro-grown strawberry plants, naturally infected C. wagneri adults efficiently transmitted Ca. P. fragariae to strawberry plants that eventually developed marginal chlorosis.