VIEW ARTICLE

Techniques

Wax Partitioned Soil Columns to Study the Influence of Soil Moisture Potential on the Infection of Wheat by Fusarium graminearum Group 1. C. M. Liddell, Fusarium Research Laboratory, Department of Plant Pathology and Agricultural Entomology, The University of Sydney, NSW 2006, Australia, Present address: Department of Plant Pathology, University of California, Davis 95616; L. W. Burgess, Fusarium Research Laboratory, Department of Plant Pathology and Agricultural Entomology, The University of Sydney, NSW 2006, Australia. Phytopathology 78:185-189. Accepted for publication 14 August 1987. Copyright 1988 The American Phytopathological Society. DOI: 10.1094/Phyto-78-185.

The influence of soil moisture potential on the infection of wheat seedlings by Fusarium graminearum Group 1 was examined using a new technique that enables accurate control of the moisture potential of infested soil surrounding the coleoptile. The coleoptile emerged through infested soil sandwiched between two wax layers. The moisture potential of the soil between the wax layers was adjusted by isopiestic or pressure membrane equilibration. The seminal roots grew in a lower soil layer maintained at a constant – 105 cm hydrostatic suction. Infection of the coleoptile occurred between saturation and –2.15 MPa soil moisture potential, and maximum infection occurred at –0.5 MPa.