xanthomonas pruni xanthomonas pruni xanthomonas pruni (syn. xanthomonas campestris pv. pruni, syn. xanthomonas arboricola pv. pruni) is a bacterial disease of almost all prunus. xanthomonas pruni scientific classification domain: bacteria phylum: pseudomonadota class: gammaproteobacteria order: xanthomonadales family: xanthomonadaceae genus: xanthomonas species: x. pruni binomial name xanthomonas pruni synonyms x. campestris pv. pruni x. arboricola pv. pruni hosts almost all prunus spp. distribution unknown in stonefruit in california until detection in sacramento and northern san joaquin valley in the spring of 2013. as of 2017 it is still restricted to those two areas. also found in almond cultivation in victoria, australia. detection palacio-bielsa et al., 2011 provides a sybr green i-based assay.: 90 management copper and mancozeb are recommended in california for almonds and have served well elsewhere. no pesticides are registered for almonds anywhere in australia. phage therapy has been heavily studied for x. pruni and some treatments have been very successful. civerolo & keil performed several experiments in the 1970s with xanthomonas pruni phage showing that peach and apricot were protected by external applications of solution. resistance resistance to copper has occurred. no copper resistance as of august 2017 in california. rotation or tank mixing is recommended to forestall resistance.