From the Editors. 445

Foreword. 447

Gengenbach, B.G. and H.W. Rines. Use of phytotoxins in selection of disease resistant mutants in tissue culture. 449

Keen, N.T. Phytoalexins and their involvement in plant disease resistance. 477

Kogan, M. Natural chemicals in plant resistance to insects. 501

Kosuge, T. Metabolic regulation in plant-pathogen interactions from the perspective of the pathogen. 529

Reese, J.C. and D.J. Schmidt. Physiological aspects of plant-insect interactions. 545

Valent, B., M.S. Crawford, C.G. Weaver, and F.G. Chumley. Genetic studies of fertility and pathogenicity in Magnaporthe grisea (Pyricularia oryzae) 559.