Submitted to: Multicrop Aflatoxin and Fumonisin Elimination and Fungal Genomics Workshop-The Peanut Foundation
Publication Type: Abstract Only
Publication Acceptance Date: 11/10/2007
Publication Date: 1/15/2008
Citation: Holbrook Jr, C.C., Wilson, D.M., Timper, P., Guo, B., Sullivan, D.G. 2007. Is crop resistance through conventional breeding relevant to reducing aflatoxin contamination? [abstract]. In: Proceedings of the 2007 Annual Multicrop Aflatoxin/Fumonisin Elimination and Fungal Genomics Workshop, October 22-24, 2007, Atlanta, GA. p. 115. Interpretive Summary: not required
Technical Abstract: During this 20th annual meeting of the Multicrop Aflatoxin Elimination Group we thought it would be appropriate to evaluate whether crop resistance through conventional breeding is relevant to reducing aflatoxin contamination. Our presentation revolved around this issue, with a primary focus on results from peanut. There are two requirements for successful plant breeding. First, there must be genetic variation for the trait of interest. Second, we must have accurate and reliable screening techniques that can be used to identify individuals with favorable genetic combinations. Results presented in this and previous workshops have clearly indicated that there is genetic variation for reduced aflatoxin contamination in corn and tree nuts. Conventional breeding has not be an important focus for the cotton group, however, preliminary data has been presented that indicated there is also genetic variation for this trait in cotton. For peanut, we screened the core collection and identified 11 accessions that showed at least a 50% reduction in aflatoxin over multiple environments. Drought tolerant material was also evaluated resulting in the identification of 10 additional accessions that showed at least a 50% reduction in aflatoxin. It is likely that work in the area of molecular genetic will also add to the genetic variability available for conventional breeding efforts. Accurate and reliable screening techniques are more problematic. Environmental effects on aflatoxin contamination for all crops are large, and data sets typically have large CV=s. We have developed rainout shelters and a field inoculation technique to reduce CV=s. We also use a data scaling system so that we can make comparisons across environments. We have used the tools we have to develop late generation breeding lines with relatively low aflatoxin and relative high yield, and are releasing C76-16 as peanut germplasm with improved resistance to drought and aflatoxin contamination. Additional releases of germplasm and/or cultivars are expected. Peanut root-knot nematodes have been shown to increase aflatoxin contamination of peanut. We have recently released Tifguard as a nematode resistant cultivar, and hope it can be used as a tool to reduce aflatoxin contamination throughout the Southeastern peanut production region. It seems likely that crop resistance through conventional breeding will play a critical role in reducing aflatoxin contamination in U.S. agriculture.