DNA Sequencing Analysis of African Xanthomonas oryzae pv. oryzae Virulence Gene (AXaVrg) DNA Marker

Global rice production is constrained by bacterial leaf blight (BLB) disease caused by pv. ( ). BLB disease incidence in West Africa was between 70–85% and yield loss in farmers’ fields was in the range of 50–90% from 2005 to 2010. In the present study, African virulence gene OPP-17 DNA marker was identified and purified using randomly amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) products from 50 isolates. Genomic DNA of 50 isolates were analyzed using OPP-17 primer in RAPD-PCR during which African virulence gene OPP-17 DNA marker was identified, purified, cloned, and sequenced. Cloning and DNA sequencing of African virulence gene OPP-17 DNA generated a 1953 bp nucleotide sequence consequently tagged as -1953. BLAST homologous analysis of the 1953 sequence provides comprehensive identification of the type II secretion genes and secreted proteins, type III secretion genes and secreted proteins in African virulence gene. Phylogenetic unweighted pairgroup method arithmetic (UPGMA) analysis revealed the African -1953 sequence was distinct from the other virulence gene sequences from China, Japan, Korea, Germany, and the United States. This information is potentially useful for effective management of BLB disease in West Africa.