VIEW ARTICLE

Ecology and Epidemiology

Some Properties of the False Broomrape Causal Agent and its Persistence in Soil and Refrigerated and Frozen Tumor Tissues. L. W. Nielsen, Professor Emeritus, Department of Plant Pathology, North Carolina State University, Raleigh, NC 27607; Phytopathology 68:1068-1070. Accepted for publication 29 December 1977. Copyright © 1978 The American Phytopathological Society, 3340 Pilot Knob Road, St. Paul, MN 55121. All rights reserved.. DOI: 10.1094/Phyto-68-1068.

The false broomrape causal agent from ground tobacco root tumors suspended in a buffer solution sedimented from suspension at 48,000 g for 20 min, was retained on a 0.45 μm filter, was inactivated with chloroform, and was insensitive to streptomycin sulfate. These responses to the treatments are similar to those of some pathogenic bacteria. The agent persisted 5 yr in an artificially infested sand-soil mixture exposed to meteorological conditions. It was recovered from tumors refrigerated at approximately 6 C for 1 yr and tumors frozen at –20 C for 4.5 yr. The level of infection obtained on tobacco assay plants indicated the causal agent might persist more than 5 yr in a sand-soil mixture and 4.5 yr in frozen tumor tissues.