SURVEY OF PATHOGENIC GENERA OF FUNGI ON FOLIAGE OF WEEDS IN MISSISSIPPI

Fungi were isolated from surface-disinfested foliar tissue samples of 35 weed species occurring in or near 67 cultivated fields in Mississip pi. Phomopsis/Diaporthe was isolated from 31 weed species, Colletotric hum/Glomerella from 23, Cercospora from 23, Alternaria from 20, Phyllo sticta from 15, Fusarium from 12, and Curvularia from six. Weed specie s yielding the greatest diversity of fungi were common cocklebur, tall morningglory, prickly sida, sicklepod, smallflower morningglory, spot ted spurge, redroot pigweed, hemp sesbania, hophornbeam copperleaf, ec lipta, and common ragweed. Species of fungi isolated were Colletotrich um capsici, C gloeosporioides, C dematium, Fusarium equiseti, F. oxysp orum, F. pallidoroseum (F. semitectum), F. roseum, Phomopsis longicoll a, and P. phaseoli. The teleomorphs of C gloeosporioides and P. phaseo li were also isolated. This information could assist in the selection of mycoherbicides.