Cohen, R., Department of Plant Pathology, Faculty of Agricultural Science, Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100, Israel
Yarden, O., Department of Plant Pathology, Faculty of Agricultural Science, Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100, Israel
Hadar, Y., Department of Plant Pathology, Faculty of Agricultural Science, Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100, Israel

The effect of Mn2+ amendment on peroxidase gene expression was studied during Pleurotus ostreatus growth on cotton stalks. Four peroxidase-encoding genes were expressed differentially and in a manner different from that observed in defined media. Mn2+ affects mnp3 expression even 2 h after its addition to the cultures, suggesting a direct effect of the metal ion on expression.