Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: April 1, 2001
Publication Date: July 1, 2001
Technical Abstract: Fusarium species infect grains and cereals causing billions of dollars in losses to the agricultural markets. F. graminearum-infected grain decreases seed germination and seedling emergence, causes post-emergence seedling death, Fusarium head blight, and reduces yield. The fungus also produces the mycotoxins, deoxynivalenol and zearalenone. Current seed treatments are effective against surface fungi on grains but have limited effects on the control of systemic persistent fungal infection that can produce seedling blight and scab. A patented endophytic bacterium, Bacillus mojavensis, a species within the B. subtilis subgroups, was studied to determine its potential as an endophytic biocontrol for F. graminearum which produces seedling blight of wheat and mycotoxins. The protection of eight commercial varieties of hard red spring and soft red winter wheat by this bacterium under growth room and greenhouse tests for control of seedling blight, and the overall effects of the bacterium on plant growth were determined. This bacterium was antagonistic in vitro to numerous fungi including F. graminearum. Data from plant growth room and greenhouse studies indicated that B. mojavensis inoculated kernels reduced endophytic seedling colonization and seedling blight disease from F. graminearum, and increased the number of germinating seeds, rate of seed germination, and seedling root and shoot growth in the eight wheat varieties tested, including the highly susceptible variety Norm. The results established that this endophytic bacterium has strong potentials for reducing seedling blight in major wheat cultivars.