Weeds always cause serious problems in pome fruit orchards. These plant species are primary, secondary and epiphytic hosts of some major plant bacteria which upon transmission to fruit trees may result in bacterial infection and crop loss .These weeds include annuals and perennials. The most prevalent perennial and spring annual weeds that serve as secondary hosts were collected during two years of study (2011-2012). Samples were examined for determining incidence of bacteria via conventional bacteriological methods. The more frequent bacteria were identified and checked for pathogenicity and epiphytic phases. Results showed that Xanthomonas spp., Pseudomonas spp. and Erwinia spp. were found on Avena fatua, Sorghum halepense, Cynodoun dactylon, Agropyron repense, Hordeum vulgare and Poa sp. as epiphytes. These bacteria could be isolated during spring. Pseudomonas syringae pv. syringae was isolated from some Poaceae species. Erwinia amylovora, the causal agent of fire blight, was isolated from Cynodon dactylon and Agropyron repense.
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