ARS | Publication request: LABORATORY AND FIELD SCREENING OF PEANUT GERMPLASM FOR SOURCES OF RESISTANCE TO PREHARVEST AFLATOXIN CONTAMINATION

Submitted to: Multicrop Aflatoxin and Fumonisin Elimination and Fungal Genomics Workshop-The Peanut Foundation
Publication Type: Abstract Only
Publication Acceptance Date: September 10, 2004
Publication Date: October 1, 2004
Citation: Guo, B., Liang, X., Holbrook, Jr., C. C. 2004. Laboratory and field screening of peanut germplasm for sources of resistance to preharvest aflatoxin contamination. In: Proceedings of the 17th Aflatoxin Elimination Workshop, October 25-28, 2004, Sacramento, California.

Technical Abstract: Peanut germplasm and breeding lines from China, India (International Crop Research Institute for the Semi-Arid Tropics), and Tifton/Georgia were evaluated in the laboratory and in the field rain-out shelters for sources of resistance to Aspergillus flavus infection and preharvest aflatoxin contamination. Total protein extracts were also analyzed by 1-D and 2-D polyacrylamide gel electrophoresis. In the laboratory bio-assay, marked differences in fungal colonization were detected among the tested genotypes at 7 days after inoculation. In the field evaluation, the experiment was randomized completely block design with 9 replications in 2003 and 2004. Only the 2003 data are presented. The aflatoxin levels were ranged from 4 ppb to 163 ppb. GT-PE2 had the lowest aflatoxin concentration and A100 had the highest. The breeding lines GT-YY20, a Spanish market-type, had 16 ppb and C34-24, a runner market-type, had 70 ppb. The differences in protein profiles were detected among the genotypes. Unique proteins have been excised from the gels for sequencing. The resistance observed in the laboratory was demonstrated in the field test in 2003. Introgression of the resistance to U.S. breeding lines has been initiated, and the resistant mechanisms are under investigation.