Occurrence in Florida of the Bacterium That Causes Bermudagrass Stunting Disease. M. J. Davis, Lauderdale Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, 3205 S.W. College Avenue, Ft. Lauderdale 33314. B. J. Augustin, Ft. Lauderdale Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, 3205 S.W. College Avenue, Ft. Lauderdale 33314. Plant Dis. 68:1095-1097. Accepted for publication 25 July 1984. Copyright 1984 The American Phytopathological Society. DOI: 10.1094/PD-68-1095.

Clavibacter xyli subsp. cynodontis, the causal agent of bermudagrass stunting disease (BSD), was frequently isolated from bermudagrass in Florida but was not constantly associated with symptoms. When Tifgreen and Tifdwarf bermudagrass (Cynodon spp.) plants were experimentally inoculated with C. xyli subsp. cynodontis from Florida and maintained in a screenhouse under about 75% shade, they developed significantly less shoot biomass than buffer-inoculated controls. Reductions in shoot and root biomass were also observed in plants vegetatively propagated from inoculated plants. When inoculated plants were transferred to better growing conditions with full sunlight, significant reductions in dry weight were not observed, suggesting that such environmental stresses as low light intensity can play an important role in the development of BSD.