|DAI, Z - South China Agricultural University|
|WU, F - South China Agricultural University|
|ZHENG, Z - South China Agricultural University|
|Yokomi, Raymond - Ray|
|KUMAGAI, L - California Department Of Food And Agriculture|
|CAI, W - South China Agricultural University|
|RASCOE, J - US Department Of Agriculture (USDA)|
|DENG, X - South China Agricultural University|
Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 3/27/2018
Publication Date: 7/28/2018
Citation: Dai, Z., Wu, F., Zheng, Z., Yokomi, R.K., Kumagai, L., Cai, W., Rascoe, J., Polek, M., Deng, X., Chen, J. 2018. Diversity of “Candidatus Liberibacter asiaticus” strains in California. Phytopathology. 108:S1.93. https://doi.org/10.1094/PHYTO-108-10-S1.1.
Technical Abstract: Citrus Huanglongbing (HLB) is a highly destructive disease and associated with a non-culturable bacterium, “Candidatus Liberibacter asiaticus” (CLas). Characterization of CLas strains is critical for HLB management. HLB was found in Florida in 2005 and is now endemic there. In California, CLas was first detected in Los Angeles County in 2012. Since then, the bacterium has been detected in multiple urban locations in southern California. Little is known about the diversity and biology of these CLas strains. In this study, nine CLas strains from six southern California cities were analyzed targeting chromosomal loci and prophage regions based on next generation sequencing (Illumina MiSeq and HiSeq). No variation was detected in 16S rRNA and nrdB gene sequences. All California CLas strains were of Asiatic origin, rather than Florida, based on terL gene grouping. Single Type 1 prophages were found in CLas strains from Anaheim, Cerritos, San Gabriel, and Riverside; Single Type 2 prophage was found in a Hacienda Heights strain; Type 1 and 3 prophages were found in a Cerritos strain, and Type 1 and 2 prophages were found in a La Habra strain. All prophages harbored Miniature Inverted-Repeat Transposable Elements (MITEs) with Type B MITEs associated to Type 1 and Type 3 prophages and Type A MITEs associated with Type 2 prophages. This information provides data useful to track the origin and pathway of the CLas strains and is critical for the management of the disease.