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Wheat (Triticum spp.) is one of the major staple food crops globally, with the USA ranking as the third-largest producer worldwide. In the southwestern US region, Durum wheat is predominantly planted under the trademarked name Desert Durum. In Arizona ~ 98% of the wheat cultivated-area correspond to Durum class. In 2024, nearly 24,000 ha were planted, resulting in a production of 190,000 tons. In April 2024, the Plant Disease Diagnostic Clinic at Yuma County Cooperative Extension, University of Arizona, received four wheat samples showing bacterial-like symptoms, including translucent stripes and leaf streaks. Incidence was estimated at ~5%. All samples were tested using the XAN ImmunoStrip test kit (Agdia Inc., Elkhart, IN, USA) resulting positive for Xanthomonas. Further, 0.5 cm2 of symptomatic leaf tissue from each sample was subjected to surface sterilization by immersion in 70% ethanol for 1 min, 1% sodium hypochlorite (NaOCl) for 2 mins, followed by rinsing with sterile distilled water. Tissues were plated on nutrient agar (NA) media and incubated at 28 °C. After 48 h, mucoid pale-yellow bacteria growth was observed in all plated samples (n = 16). Single bacterial colony were isolated from each sample by the streak plate method. All the resulting colonies exhibited morphology consistent with members of the Xanthomonas genus (Hayward 1993). Total genomic DNA was extracted from two randomly selected colonies, designated as XtpvuYPHC1 and XtpvuYPHC2. Whole-genome sequencing was performed using the Illumina NovaSeq platform with 150 bp paired-end reads, obtaining a total of 12,464,312 and 8,761,464 clean reads for XtpvuYPHC1 and XtpvuYPHC2, respectively. Genome assembly was conducted using SPAdes v3.13.1 (Bankevish et al. 2012). Assemblies resulted in 117 and 114 contigs, CG content of 68.16% and 68.07%, and coverage of 378X and 350X, respectively. Average nucleotide identity revealed ≥99% identity with Xanthomonas translucens pv. undulosa reference strains (CP008714.1, CP009750.1, NZ_CP043500.1, CP043500.1). Genome sequences were deposited in the GenBank under accession numbers JBPZIS000000000 (XtpvuYPHC1), JBPZIT000000000 (XtpvuYPHC2), and BioSample numbers (SAMN50209999 and SAMN50210000). Pathogenicity assays were conducted by inoculating XtpvuYPHC1 and XtpvuYPHC2 isolates on three different wheat varieties. A bacterial suspension (108 CFU/mL) was used to inoculate four-week-old plants using the leaf-clipping method on the third and fourth leaves (n = 141). Control plants were treated with sterile water. Plants were placed in a plastic chamber (28 ± 2 °C, 90 % RH) for 24 h and then maintained in a greenhouse (26 ± 5 °C). Soaked lesions appeared on inoculated leaves within 96 h, progressing to chlorotic lesions by 10 days post-inoculation, while control plants remained asymptomatic. Twelve symptomatic plants were randomly selected for pathogen re-isolation on NA, and the resulting re-isolation rate was 98%. Bacteria recovered from leaf lesions were subject to 16S rDNA sequencing, and their sequences share 100% identity with the XtpvuYPHC1/XtpvuYPHC2 isolates, fulfilling Koch’s postulates. To the best of our knowledge, this is the first report of X. translucens. pv undulusa in Arizona, expanding the known geographic distribution, highlighting the importance of monitoring this disease in Arizona, and providing genomic information supporting ongoing disease management efforts.