Increased susceptibility to bacterial spot of peach trees growing in soil infested with Criconemella xenoplax

Abstract

Young Suwanee peach trees were planted in soil infested or not infested with the nematode Criconemella xenoplax. Five months after soil infestation, the leaves were inoculated with Xanthomonas campestris pv. pruni to measure the influence of nematode infestation on bacterial spot development. Bacterial spot lesions in inoculated leaves were more numerous and covered a greater leaf surface area for trees growing in nematode-infested soil than for those in noninfested soil. When the trees were growing in nematode-infested soil, the leaf area diseased was slightly greater on trees in nonsteamed field soil than in soil treated with aerated steam (57 to 62°C for 75 min) prior to infestation with C. xenoplax. Results indicate that bacterial spot damage may become more severe on peach trees if the soil is infested with C. xenoplax than when nematodes have been suppressed.