Peach X-Disease: Treatment Site Damage and Yield Response Following Antibiotic Infusion. George H. Lacy, Assistant Professor, Department of Plant Pathology and Physiology, Virginia Polytechnic Institute and State University, Blacksburg 24061. Plant Dis. 66:1129-1133. Accepted for publication 16 March 1982. Copyright 1982 American Phytopathological Society. DOI: 10.1094/PD-66-1129.

X-diseased scaffolds of peach and nectarine infused with oxytetracycline hydrochloride (OTC) produced nearly normal yields. Scaffolds either immediately above treatment sites or infused directly improved most. Treatment site damage was greatest on trees with severe foliar symptoms. Trees infused by gravity and by pipets were damaged less than ones infused by Mauget cups and with concentrated OTC or injected. Calcium chloride, spectinomycin, taurolin, and tylosin caused less damage than OTC. Spectinomycin and streptomycin caused severe chlorosis and bud death above treatment sites. Erythromycin, sulfanilamide, taurolin, tylosin, and OTC caused no to moderate chlorosis. Only OTC-treated trees had significant remission of foliar symptoms.

Keyword(s): mycoplasmal diseases, pathometry, Prunus persica, P. persica var. nectarina.