Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: October 27, 2009
Publication Date: October 27, 2009
Citation: Fountain, J.C. Chen, Z.Y. Scully B.T. Kemerait, R. Lee, D. Guo, B. 2009. Comparison of Gene Expressions of Maize Kernel Pathogenesis-Related Proteins in Different Maize Genotypes. Presented at Mississippi State University on Reducing Aflatoxin Contamination in Corn meeting on October 27-28, 2009. Technical Abstract: Aflatoxins are carcinogenic mycotoxins produced by the fungus Aspergillus flavus during infection of various grain crops including maize (Zea mays). Contamination of maize with aflatoxins has been shown to be exasperated by late season drought stress. Previous studies have identified numerous resistance-associated proteins (RAPs) that may be responsible for resistance to A. flavus proliferation and aflatoxin production, This report presented the study of the expression of three genes encoding RAPs such as ZmPR-10, glyoxalase I (GLX-I), and 14-kDa trypsin inhibitor (TI) in 2007 and 2008 different field grown maize genotypes. The expression of these genes was assessed in developing kernels under drought stress versus irrigation conditions using semi-quantitative RT-PCR and real-time PCR. The data suggested that that late season drought stress affected the gene expression differently in different genotypes. The expression of PR-10 was lower overall as compared to GLX-I and TI. GLX-I had less variance in expression regardless of treatment. TI had the higher expression in compare with others, indicating that this particular protein may accumulate to a greater constitutive concentration in mature maize kernels than either PR-10 or GLX-I. Such expression patterns combined with the results of previous studies show that these stress-related resistance-associated proteins (RAP’s) may play a role in maize resistance to A. flavus infection and subsequent aflatoxin contamination.