Antifungal activity of each isolate against S. sclerotiorum was tested in dual cultures on PDA. For filamentous fungal isolates, a mycelial agar plug (6 mm in diameter) was placed on a PDA dish (9 cm in diameter) at one centimeter from the edge. For yeast-like fungal isolates, a loop of yeast-like cells of each isolate was streaked on a PDA dish also at one centimeter from the edge. A mycelial agar plug (6 mm in diameter) of S. sclerotiorum from the margin of a two-day-old colony was placed 5 cm from the endophytic fungal inoculant to establish a dual culture. There were five dishes (replicates) for each endophytic fungus. The cultures were incubated at 20 _C for 8 days. Width of the clear zone formed between the two colonies (a tested endophytic fungus and S. sclerotiorum) in each dish was measured as described in our previous study (Li et al., 2003). A fungus capable of producing an inhibition zone against S. sclerotiorum in the dual cultures was considered an antagonistic fungus and was selected for further experimentation.