Technical Abstract: Biological controls with extensive host range are needed to control major pathogens of cereals and vegetables in order to reduce economic losses, and prevent the mycotoxin accumulation in agricultural commodities. A bioprotective bacterium, Bacillus mojavensis, RRC 101 (=B. subtilis, RRC101) that colonizes the intercellular spaces of plant tissues was granted a patent, USP 5,994,117, as an endophyte for the control of plant diseases caused by fungi. Several other isolates of B. mojavensis were compared for their endophytic colonization of plants, and screened for fungal antagonism. B. mojavensis-inoculated seeds (corn, wheat, rye, oats, peas, and beans) were used to determine the host range. The endophytic bacterium inhibited several pathogens, including Pythium, Cochliobolus, Rhizopus, and Fusarium moniliforme. B. mojavensis increased the rates of seed germination, root and seedling growth, and plant maturation in corn, oats, wheat, rye, peas, and beans. The production of the fumonisin mycotoxins resulting from the endophytic colonization of corn by F. moniliforme was also reduced.