Self-, cross- and non-pollinated styles of Petunia hybrida were treated with 3-3'-diaminobenzidine for the ultrastructural localization of peroxidase activity. Wall peroxidases were absent in cross-pollinated styles, but they were detectable as an osmiophilic deposit on the cell walls of the outer portion of the transmitting tissue in self- and non-pollinated styles. The cell layer showing pero...
