RICE AND STINGING NETTLE LECTINS - INSECTICIDAL ACTIVITY SIMILAR TO WHEAT-GERM-AGGLUTININ

Previous studies have shown that lectins with specificity for GlcNAc residues, when fed in the diet of the cowpea weevil, Callosobruchus maculatus, cause delays in its development. We have begun an in vivo structure activity analysis to determine what molecular features lead to maximum lectin toxicity. Although rice lectin has a four-fold greater agglutinating activity toward mammalian erythrocytes than wheat germ agglutinin (WGA), its biological activity when fed to C. maculatus is similar to WGA. Stinging nettle lectin, a poor agglutinin, is ca two to four times less effective than WGA.