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Disease Note. First Report of Periwinkle Infection by Mycoplasmalike Organism from Field-Collected Blueberry Leafhoppers. J. L. Dale, Department of Plant Pathology, University of Arkansas, Fayetteville 72701. Jacqueline Fletcher, Department of Plant Pathology, Oklahoma State University, Stillwater 74078. Plant Dis. 71:1045. Accepted for publication 14 July 1987. Copyright 1987 The American Phytopathological Society. DOI: 10.1094/PD-71-1045C. A mycoplasmalike organism (MLO) associated with blueberry stunt
(BSMLO) is transmitted by the leafhopper Scaphytopius magdalensis
(Prov.). The MLO has been transmitted to periwinkle (Catharanthus
roseus (L.) G. Don) by dodder but not by S. magdalensis. Infection of
periwinkle via leafhoppers was attempted during 1984-1986 by
exposing 256 plants to individual S. magdalensis collected from symptomatic wild Vaccinium pallidum Ait. plants known to contain
BSMLOs (1). Symptoms of stunt infection developed in seven
periwinkle plants (2.7%), two of which were examined by electron and
fluorescence microscopy and contained MLOs. Seven nonexposed
plants showed no symptoms. Average leafhopper survival and time for
symptom development were 10 and 58 days, respectively. Because
blueberry plants require extended incubation for symptom
development, results suggest periwinkle might be a useful indicator
plant in vector transmission studies. Symptoms of the blueberry MLO
on periwinkle resembled those from dodder transmission and also
infection by Spiroplasma citri and S. kunkelii. ELISA tests of affected
periwinkle plants with antiserum specific for S. citri and S. kunkelii
were negative. |