Abstract
The abundance of spores of Colletotrichum gloeosporioides, (Penz.) Sacc., the cause of lychee anthracnose, on the surfaces of leaves, inflorescences, and fruits was measured in three groves of 'Mauritius' lychee (Litchi chinensis Sonn.) in south Florida. Few spores of the pathogen were detected until those portions of inflorescences, which did not set fruit, began to die and provide a substrate for growth and sporulation of the pathogen. Precipitation events and warm weather apparently aided development and dispersal of spores. Greater numbers of spores were consistently detected on inflorescence tissues than on leaves. Few spores were detected on fruit surfaces, and then only when high populations were detected on leaves and peduncles. Nevertheless, mature fruits held in a moist chamber frequently developed necrotic lesions from which C. gloeosporioides was isolated. The results of the present study suggest the possibility that fungicide application for control of lychee anthracnose might be limited to periods of time conducive to inoculum build-up.
