Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 10/16/2006
Publication Date: 5/17/2007
Citation: Hawkins, L.K., Luthe, D.S., Windham, G.L., Williams, W.P. 2007. Effect of exogenous jasmonic acid application on Aspergillus flavus kernel infection and aflatoxin production in two maize hybrids (Zea mays L.) [abstract]. In: Proceedings of the 2006 Multicrop Aflatoxin/Fumonisin Elimination & Fungal Genomics Workshop, October 16-18, 2006, Ft. Worth, Texas. p. 98.
Technical Abstract: Jasmonic acid (JA), produced by the octadecanoid pathway, is a phytohormone that triggers induced resistance against certain pathogens and arthropod herbivores. The octadecanoid pathway has been implicated in playing a role in the Aspergillus flavus-maize seed interaction. In field studies, the effect of exogenous applications of nonphytotoxic levels of JA at 8 and 13 days after midsilk were evaluated in two maize hybrids differing in resistance to A. flavus infection (Mo18W X Mp313E and GA209 x Mp339) for any effect on kernel infection by A. flavus, subsequent aflatoxin accumulation, and a natural infection of Fusarium verticillioides. As a parent in single crosses, Mp313E has been effective in reducing aflatoxin contamination levels in other studies. An application of 71.5 µg JA•plant-1, whether applied topically to silks or injected directly into the side of the ear, did not have a significant effect on reducing aflatoxin production. There were significant differences in aflatoxin accumulation and kernel infection by A. flavus and F. verticillioides between the two hybrids. GA209 x Mp339 tended to have higher levels of A. flavus kernel infection (7%) and aflatoxin (477 ng•g-1); yet, lower levels of F. verticillioides (14%) than Mo18W x Mp313E with 2% A. flavus kernel infection, 145 ng•g-1 aflatoxin, and 26% F. verticillioides infection. This concentration of jasmonic acid is ineffective in reducing A. flavus kernel infection and aflatoxin accumulation in an agronomical setting.