1. K. S. Century, A. D. Shapiro, P. P. Repetti, D. Dahlbeck, B. J. Staskawicz, Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720–3102, USA.
2. E. Holub, Plant Pathology and Weed Science Department, Horticulture Research International–Wellesbourne, Warwickshire CV35 9EF, UK.