Lin et al. (2012) has recently made first report on identification of bacterium Dickeya dieffenbachiae in China. Bacteria cause soft rot of Philodendron and can be transffered by plants and growing medium.
Philodendron is a popular foliage plant cultivated in interiorscapes of homes, offices, and malls throughout China. A severe outbreak of a soft rot of Philodendron ‘Con-go’ occurred in Guangzhou, China from 2010 to 2011. The disease was characterized by leaf infections starting as pinpoint spots that are water soaked and yellow to pale brown. The lesions are sometimes surrounded by a diffuse yellow halo. When the humidity is high and temperatures are warm to hot, the spots expand rapidly, becoming slimy, irregular, and sunken with light tan centers, darker brown borders, and diffused yellow margins and may involve the entire leaf in a few days. An invasion of the midrib and larger veins by the causal bacterium often results in advancement into the petiole and stem.
A survey of three areas of production of Philodendron ‘Con-go’ (5 ha) in Guangzhou revealed that 91% of the fields were affected at an incidence ranging from 15 to 30%. Biolog analysis identified the isolates as Pectobacterium chrysanthemi alias Dickeya sp. PCR and other molecular tests followed by bioassey identified Dickeya dieffenbachiae, which ia a causal agens of soft rot of Philodendron ‘Con-go' in China.
Lin BR, Shen HF, Zhou JN, Pu XM, Chen ZN, Feng JJ (2012) First Report of a Soft Rot of Philodendron ‘Con-go’ in China Caused by Dickeya dieffenbachiae.- Plant Disease 96(2012)3 p 452. http://dx.doi.org/10.1094/PDIS-09-11-0795