Pathogenicity and Molecular Characterization of Burkholderia cepacia Causing Sour Skin Disease of Onion (Allium cepa)
D. Dimayacyac, and M. Balendres (33-43)
Abstract
In this study, Burkholderia cepacia was identified as the causal agent of sour skin disease of onion in the Philippines. The bacterium’s identity was validated by analyzing the DNA sequence of the 16S ribosomal RNA gene region. The Philippine isolate had 99.51% identity to B. cepacia (GenBank accession number: KF681774). B. cepacia caused sour skin symptoms in inoculated red and yellow onions. Repeated assays also revealed that scallions are susceptible to B. cepacia infection. Since B. cepacia was previously reported to infect bulb onions in the field and this study showed severe rotting once the disease developed during storage, efficient detection methods and integrated pest management strategies would be needed to reduce the source of inoculum in the field and mitigate disease development when onion bulbs are in storage.