Influence of Soil Matric Potential and Soil pH on Cephalosporium Stripe of Winter Wheat in the Greenhouse. J. C. Anderegg, Former Postdoctoral Research Associate, Department of Plant Pathology, Washington State University, Pullman 99164-6430. T. D. Murray, Assistant Professor, Department of Plant Pathology, Washington State University, Pullman 99164-6430. Plant Dis. 72:1011-1016. Accepted for publication 29 June 1988. Copyright 1988 The American Phytopathological Society. DOI: 10.1094/PD-72-1011.

The incidence of Cephalosporium stripe in winter wheat grown in the greenhouse increased twofold to fourfold as soil pH (1:2 in 0.01 M CaCl₂) decreased from 7.5 to 4.5; disease severity followed a similar pattern. Incidence of disease increased from twofold to 12-fold as soil matric potential increased from –1.0 to –0.1 bar. Cultivar Stephens exhibited two to three times more disease than either Nugaines or Daws, which were equally susceptible based on incidence and severity of disease. Ratings of these cultivars in the greenhouse correspond closely to ratings obtained under field conditions. In general, these cultivars were affected similarly by soil pH and soil matric potential. The development of severe disease in greenhouse-grown plants in the absence of frozen soil indicates that these factors are not requisite for infection of wheat by Cephalosporium gramineum, as previously proposed. It may be possible to screen cultivars for resistance to C. gramineum in the greenhouse faster and more reliably than current field screening methods by combining the soil factors most favorable for disease development.