Disease Note.

First Report of Fusarium Wilt of Basil in Louisiana. G. E. Holcomb, Department of Plant Pathology and Crop Physiology, and Burden Research Plantation, Louisiana Agricultural Experiment Station, Louisiana State University Agricultural Center, Baton Rouge, LA 70803. Plant Dis. M. J. Reed, Department of Plant Pathology and Crop Physiology, and Burden Research Plantation, Louisiana Agricultural Experiment Station, Louisiana State University Agricultural Center, Baton Rouge, LA 70803. Plant Dis. 78:1218. Accepted for publication 4 October 1994. Copyright 1994 The American Phytopathological Society. DOI: 10.1094/PD-78-1218F.

Symptoms of leaf chlorosis, wilt, leaf drop, vascular discoloration, and shoot and plant death were observed in basil plants (0cimum basilicum L.) from commercial and experimental outdoor plantings in spring 1994. Eighteen thousand container-grown plants were destroyed by a commercial grower because of high disease incidence. Isolations on acidified potato dextrose agar from stem sections of infected plants consistently yielded Fusarium oxysporum Schlechtend.:Fr. f. sp. basilicum Dzid-zariya. Pathogenicity tests were performed on 5-7 cm tall basil seedlings by dipping their roots in an aqueous suspension of 1.25 x 106 spores per milliliter. Twenty-four inoculated seedlings and 24 noninoculated controls were planted in separate styrofoam flats (6.4 cm' cells) and watered in. Wilt and death of all inoculated seedlings occurred after 14 days and F. o. basilicum was reisolated from root and stem tissues of 17 of 17 seedlings sampled. Fusarium wilt of basil was first reported in the U.S. from Massachusetts (2) and California (1).