Submitted to: North American Alfalfa Improvement Conference
Publication Type: Abstract Only
Publication Acceptance Date: August 3, 1998
Publication Date: N/A
Technical Abstract: Transgenic crop plants engineered for resistance to insect pests are now part of several pest management systems. Current insect resistance research deals primarily with the introduction of insecticidal proteins derived from soil bacteria or from plant species other than the one of interest. In vivo laboratory bioassays conducted in our laboratory have demonstrated that selected microbial and synthetic cysteine proteinase inhibitors significantly inhibited alfalfa weevil foliar feeding, pupation, adult emergence, and fecundity. Several plant lectins also were identified which significantly inhibited many of these same variables. Two cDNA clones of cysteine proteinase inhibitor genes from rice have been recloned into an E. coli expression vector for recombinant protein syntheses and their effects tested in vivo on alfalfa weevil growth and development and in vitro on alfalfa weevil midgut activity. These same genes have been reconstructed for expression in plant cells, cloned into transformation vectors carrying reporter and selectable marker genes and introduced into alfalfa explants via Agrobacterium-mediated gene transfer methods. Regenerated alfalfa transformants are currently being vegetatively propagated and will be characterized for protein expression of the inhibitor genes by molecular techniques and in vivo laboratory insect bioassays.