VIEW ARTICLE

Ecology and Epidemiology

Effects of Hydrogen Fluoride on Growth, Common Blight Development, and the Accumulation of Fluoride in Field-Grown Red Kidney Beans. K. L. Reynolds, Department of Plant Pathology, Cornell University, and Boyce Thompson Institute for Plant Research, Ithaca, NY 14853-1801; J. A. Laurence, Department of Plant Pathology, Cornell University, and Boyce Thompson Institute for Plant Research, Ithaca, NY 14853-1801. Phytopathology 78:1168-1173. Accepted for publication 11 March 1988. Copyright 1988 The American Phytopathological Society. DOI: 10.1094/Phyto-78-1168.

Field-grown California Light Red Kidney bean plants were spray-inoculated with a suspension of rifampin-resistant Xanthomonas campestris pv. phaseoli and exposed intermittently to hydrogen fluoride (HF) at 0, 2, or 4 μg F m^–3 in open-top chambers during the summers of 1984 or 1985. Plants were exposed for 8 hr day^–1, 2 days each week for 9 wk in 1984 or for 8 hr day^–1, 4 days each week for 10 wk in 1985. Foliar accumulation of fluoride, disease severity, and epiphytic populations of the pathogen and other (unidentified) leaf surface microorganisms were determined weekly. The area under disease progress curve and final disease severity were not affected by exposure to HF, but the apparent infection rate increased with an increase in concentration of HF in 1985. There was no effect of exposure to HF on growth of epiphytic populations of the pathogen or on the populations of other epiphytic bacteria during either year. However, in both years the growth rate of fungal populations increased with an increase in concentration of HF. Yield was not affected by HF in 1984 but decreased with an increase in concentration of fluoride in foliar tissues in 1985.