Submitted to: American Peanut Research and Education Society Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: April 16, 1996
Publication Date: N/A
Technical Abstract: Studies were conducted during 1994 and 1995 in the Environmental Control Plot Facility at the NPRL to determine the effect of different inoculum rates of biological control agents on preharvest aflatoxin contamination of Florunner peanuts. Biocontrol agents were non-toxigenic color mutants of Aspergillus flavus and A. parasiticus that were grown on rice for use as soil inoculum. Three replicate plots (4m X 5.5m) were treated with 0, 20 100, or 500 lb/A of an equal mixture of the color mutants at 23 days after planting (DAP) in 1994. The same plots received identical treatments in 1995 with inoculation occurring at 47 DAP. Aflatoxin analyses of all peanuts were made by HPLC and showed a treatment-related effect with a reduction of aflatoxin in peanuts from all treatments compared with the untreated controls. In 1994 treatment means were 338, 74, 35, and 33 ppb for the 0, 20, 100, and 500 lb/A treatments, respectively. The 1995 means were 718, 184, 36, and 0.4 ppb for the same treatments. Compared with untreated controls, the 20, 100, and 500 lb/A treatments produced reductions in aflatoxin of 78.1, 89.6 and 90.2%, respectively, in 1994 and 74.4, 95.0, and 99.9%, respectively, in 1995. These data indicate that excellent control of preharvest aflatoxin contamination of peanuts is possible with this strategy.