Control of Cladosporium caryigenum on Pecan Leaves and Nut Shucks with Propiconazole (CGA-64250). A. J. Latham, Department of Botany, Plant Pathology and Microbiology, Alabama Agricultural Experiment Station, Auburn University, Auburn, AL 36849. J. M. Hammond, Field Research Representative, Ciba-Geigy Corp., Charlotte, NC 28210. Plant Dis. 67:1136-1139. Accepted for publication 24 April 1983. Copyright 1983 American Phytopathological Society. DOI: 10.1094/PD-67-1136.

After-infection control of Cladosporium caryigenum on pecan (Carya illinoinensis) was obtained for 5 days on leaves sprayed to runoff with 270 mg propiconazole per liter of water. Application of propiconazole 6 or 8 days after inoculation resulted in survival of C. caryigenum 3 or 23% as great, respectively, as on lesions of unsprayed leaves. Development of scab lesions on nut shucks inoculated at intervals after propiconazole treatment indicated fungicide deterioration was significant between 15 and 18 days. Propiconazole was not translocated from one leaflet to another in sufficient quantity to control scab.