VIEW ARTICLE

Ecology and Epidemiology

Effect of Exchangeable Soil Aluminum and Alkaline Calcium Salts on the Pathogenicity and Growth of Phytophthora capsici from Green Pepper. J. J. Muchovej, Assistant professor, Departamento de Fitopatologia, Universidade Federal de Viçosa, Viçosa, 36 570, MG, Brazil; L. A. Maffia(2), and Rosa M. C. Muchovej(3). (2)Assistant professor, Departamento de Fitopatologia, Universidade Federal de Viçosa, Viçosa, 36 570, MG, Brazil; (3)Graduate student, Departamento de Solos, Universidade Federal de Viçosa, Viçosa, 36 570, MG, Brazil. Phytopathology 70:1212-1214. Accepted for publication 23 June 1980. Copyright 1980 The American Phytopathological Society. DOI: 10.1094/Phyto-70-1212.

In greenhouse studies CaCO₃ or Ca(OH)₂, but not CaSO₄ or CaCl₂ significantly increased seedling blight caused in green pepper by Phytophthora capsici. This enhancement of disease is attributed to immobilization of exchangeable soil aluminum by CaCO₃ and Ca(OH)₂, but not by CaSO₄ or CaCl₂. There was no relationship between tissue calcium and disease. In vitro reduction in mycelial growth occurred in culture media amended with Al⁺³ at levels corresponding to natural levels in soil. P. capsici was recovered from all soils indicating that suppression was fungistatic rather than fungitoxic.