Submitted to: Maize Genetics Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 2/3/2006
Publication Date: 3/6/2006
Citation: Luo, M., Lee, R.D., Guo, B. 2006. Microarray-based pathway analysis of maize kernels with drought tolerance and low aflatoxin contamination [abstract]. In: Proceedings of the 48th Annual Maize Genetics Conference, March 9-12, 2006, Pacific Grove, CA. p. 187. Interpretive Summary:
Technical Abstract: Aflatoxin contamination caused by Aspergillus fungi is a greatest concern in corn production world wide. Pre-harvest A. flavus infection usually happens when corns suffer drought stress at late developmental stages. However, drought resistant lines displayed less aflatoxin contamination under same situation. Although mechanisms adapted to water stressed environments are widely reported in the maize kernels, but the majorities are focused on the early stages of kernel development. It is still unclear about the molecular mechanisms of drought tolerant lines with low aflatoxin contamination under water deficit. One hypothesis is that some metabolic pathways in the developing kernels are affected differently in drought tolerant and sensitive lines under water deficit stress. The objective of this study is to test this hypothesis and to better understand the changes of gene expression in response to drought stress during the late stages of seed development, and to identify the related biochemical pathways and resistant genes. The maize inbred lines of Tex6 and B73 were used in this study. Tex6 has been reported to have resistance to Aspergillus infection and reduced preharvest aflatoxin contamination. B73 is used as a susceptible control. Transcriptional profiles of kernels at the 25, 30, 35, 40, 45 day after pollination were compared under normal and water deficit conditions using the 70-mer maize oligonucleotide arrays (version 1, ~58,000 sequences) from Maize Oligonuleotide Array Project. Several inbred lines with different tolerance of drought stress and A. flavus infection were used in the research to validate the microarray study using real time PCR.