Brown spot caused by Sphingomonas sp on yellow Spanish melon fruits in Spain

Brown fruit spot symptoms were observed on yellow Spanish melons (Cucumis m elo var. inodorus) grown in greenhouses at Almeria in Spain. Nonsporing, mo tile, rod-shaped bacteria were isolated from diseased fruits, which on nutr ient agar produced small yellow colonies. Two bacterial isolates, used for further investigations, were pathogenic on fruits but not on cotyledons of Spanish melon plants. They provoked disease symptoms similar to those obser ved in the greenhouse. Both isolates were Gram-negative, catalase-positive, weakly oxidase-positive and phenylalanine deaminase-negative, They hydroly sed esculin but not gelatin and they utilized glucose oxidatively. Fatty ac id analysis revealed that both isolates belong to the genus Sphingomonas. I n addition, 16S rDNA sequence analysis, performed on one isolate, demonstra ted that it had a significant sequence similarity (more than 98%) with Sphi ngomonas pruni and Sphingomonas mall, nonphytopathogenic bacteria isolated from plants. Although enterobacterial repetitive intergenic consensus PCR a nd repetitive extragenic palindromic PCR seem to indicate that the Sphingom onas isolates from Spanish melon fruits may belong to a new species, DNA-DN A hydridization analysis is necessary to verify this hypothesis.