Theses and Dissertations

Issuing Body

Mississippi State University


Willeford, Kenneth

Committee Member

Warburton, Marilyn

Committee Member

Brown, Ashli

Date of Degree


Document Type

Graduate Thesis - Open Access



Degree Name

Master of Science


College of Agriculture and Life Sciences


Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology


An efficient approach to combat the accumulation of aflatoxin is the development of germplasm resistant to infection and spread of A. flavus in maize, one of the most important cereal grains in the world. Lipoxygenases (LOXs) are a group enzymes that catalyze oxygenation of polyunsaturated fatty acids (PUFAs). LOX derived oxilipins play critical roles in plant defense against pathogens such as A. flavus. The objectives of this study were to report sequence diversity and expression patterns for all LOX genes, and map their effect on aflatoxin accumulation via linkage and association mapping. Genes GRMZM2G102760 (ZmLOX 5) and GRMZM2G104843 (ZmLOX 8) fell under previously published QTL in one of four mapping populations and appear to have a measurable effect on the reduction of aflatoxin in maize grains. The association mapping result shows 19 of the total 215 SNPs found within the sequence of the ZmLOXs were associated with reduced aflatoxin levels.