<p>Control aflatoxin contamination of cottonseed through incorporation of foreign antifungal genes into cotton by genetic engineering. Enhance resistance to Aspergillus flavus invasion in corn and cotton through induction of native host plant defense chemicals. Determine plant stress effects on ability of cotton to mount defenses against A. flavus. Identify resistant corn inbreds by assessing degree of kernel invasion by reporter gene-containing A. flavus strains.</p>
Cotton meristematic tissue will be transformed with antifungal genes via the biolistic method and regenerated into fully developed cotton plants. To assess the effectiveness of candidate genes to inhibit growth of A. flavus in cotton, genes will be placed under constitutive control using the CaMV 35S promoter. Genes effective against A. flavus will be placed under more selective control (e.g., seed specific expression) using specific promoter elements. Cottonseed and corn kernels will be treated with elicitors derived from fungal cell walls and/or the lipoxygenase pathway in cotton to test for induction of native plant resistances to A. flavus. Anatomical and biochemical changes will be measured in cotton which are related to water and/or nutrient stress and to defensive capabilities against A. flavus invasion. A reporter gene-containing tester strain of A. flavus will be used to detect and localize antifungal activities/traits in individual corn kernels of inbred lines used in production of commercially used corn hybrids.
<ol> <li>Cleveland, T.E., Bhatnagar, D., Yu, J., Chang, P-K., Rajasekaran, K., Brown, R.L., Cary, J.W. Metabolic engineering applications for control of aflatoxin produced by Aspergillus species. Society for Industrial Microbiology Meeting. 1999.
<li>Cleveland, T.E., Brown, R.L., Chen, Z., Cary, J.W., Rajasekaran, K., Jacks, T.J., Bhatnagar, D. Identification of antifungal genes from corn and other sources for enhancement of host plant resistance to invasion by mycotoxin-producing fungi. Fumonisin Risk Assessment Workshop. 2000.
<li>Rajasekaran, K., Cary, J.W., Cleveland, T.E. Expression of a gene encoding a synthetic antimicrobial peptide confers fungal resistance in vitro and in planta in transgenic plants. 6th International Conference on Plant Molecular Biology. 2000.
<li>Jacks, T.J., Rajasekaran, K., Cary, J.W., Cleveland, T.E., van Pee, H.-K. Increased disease resistance in transgenic plants expressing a bacterial nonheme chloroperoxidase gene. World Congress Biotechnology.11th International Biotechnology Symposium and Exhibition. 2000.</ol>