Submitted to: Multicrop Aflatoxin and Fumonisin Elimination and Fungal Genomics Workshop-The Peanut Foundation
Publication Type: Abstract only
Publication Acceptance Date: 12/15/2006
Publication Date: 2/1/2007
Citation: Holbrook Jr, C.C., Cantonwine, E., Guo, B., Timper, P., Sullivan, D.G., Wilson, D.M. 2007. New Approaches to Breeding for Resistance to Preharvest Aflatoxin Contamination in Peanut. Proc. Aflatoxin Elimination Workshop p. 58. Interpretive Summary: not required
Technical Abstract: On average, preharvest aflatoxin contamination (PAC) costs the U.S. peanut industry over $20 million annually. The long-term objective of this research program is to develop peanut cultivars which have less aflatoxin contamination. During the coarse of this project we have developed field screening techniques that can measure genetic differences in aflatoxin contamination. We have also identified several sources of resistance. These sources of resistance have been entered into a hybridization program to attempt to combine this resistance with high yield, acceptable grade, and resistance to tomato spotted wilt virus (TSWV). This has resulted in the development of breeding lines with relatively high yield and relatively low aflatoxin when grown under heat and drought stress. We are releasing C76-16 as peanut germplasm with improved resistance to drought and aflatoxin contamination. We continue to looks at new approaches which could be used to accelerate our breeding progress. During the past year we evaluated epidermal conductance as a potential drought tolerance trait, and evaluated genetic response to in vitro seed colonization by Aspergillus flavus in peanut. The genetic variation in epidermal conductance does not appear to be large enough to be useful in our breeding program. We did observe some interesting genetic difference in in vitro seed colonization and we plan to conduct some additional studies on this approach. The most promising approach to accelerate the development of PAC resistant peanut may be the use of nematode resistance. Previously, we have documented an association between root-knot nematode damage and increase PAC. We plan to release C724-19-15 as a nematode resistant cultivar this winter, and hope that this cultivar can be used as a tool to reduce PAC on the farm level.