Submitted to: Multicrop Aflatoxin and Fumonisin Elimination and Fungal Genomics Workshop-The Peanut Foundation
Publication Type: Abstract only
Publication Acceptance Date: 9/10/2004
Publication Date: 10/1/2004
Citation: Moore, S., Abbas, H.K., Guo, B., Krakowsky, M.D., Clements, M.J., Brooks, T.D., Williams, P.C., Windham, G.L., White, D., Xu, W., Iskeit, T., Betran, J. 2004. Southeastern Regional Aflatoxin Test (SERAT) [abstract]. In: 2004 Fungal Genomics and Aflatoxin/Fumonisin Elimination Workshop, October 25-28, 2004, Sacramento, CA. Interpretive Summary: Interpretive summary not required.
Technical Abstract: Aflatoxin, a potent toxin and carcinogen produced by the fungus Aspergillus flavus, limits corn marketability, causes enormous economic losses, and poses a risk to animal and human health. Aflatoxin contamination of corn grain is a chronic problem for growers in the southeast United States. For several years, research groups at Louisiana, Mississippi, Georgia, Illinois and Texas have been screening corn germplasm for response to aflatoxin contamination at specific locations. Although several sources of resistance have been identified and released, at present, there are no elite inbred lines resistant to aflatoxin that can be used directly in commercial hybrids. Aflatoxin accumulation is severely affected by the environment. Genotype by environment interaction is normally significant with genotypes showing different relative response across environments. A testing network of environments across major growing areas affected by aflatoxin has been established to identify the most consistent stable sources of resistance. SERAT is a multilocation and multistate regional test of the most promising germplasm from each breeding program. Participants provide seed of a few hybrids and a testing location. Evaluations are conducted under inoculation with A. flavus following the protocols commonly used by each research group. In addition to aflatoxin, grain yield and other agronomic traits such as maturity, lodging, grain moisture, test weights, etc. are recorded. Each research group conducts the analysis for its location and single location data are compiled and analyzed across environments. In 2004, SERAT tests were conducted at six locations: Alexandria, LA; Tifton, GA; Starkville, MS; Urbana, IL; Halfway, TX; and Weslaco, TX. The silk channel inoculation method was used at all locations except Urbana, where inoculation with a pinboard was used, and Starkville, where inoculum was injected through husk leaves into the side of the ear. Currently we have aflatoxin accumulation data for Weslaco and Alexandria. Aflatoxin concentrations in Weslaco ranged from 31 ng g-1 to 3709 ng g-1 with an average of 652 ng g-1. Average aflatoxin concentration at Alexandria was 730 ng g-1 with a range from 56 to 1759 ng g-1. In general, some experimental hybrids had less aflatoxin but lower yield than commercial checks. Response of materials from different programs was variable, in that hybrids showed desirable expression for different traits such as aflatoxin, grain yield and standability. This suggests possibilities of combining positive traits by crossing germplasm from different programs. With this collaborative regional testing, we expect to identify the most stable sources of aflatoxin resistance, assess their consistency across different environments and treatments, characterize their agronomic performance, increase the collaboration among research groups in different states, and to assess the magnitude and nature of genotype x environment interaction for aflatoxin.