Transgenic corn expressing a Cry9C insecticidal protein from Bacillus thuringiensis protected from European corn borer damage

The European corn borer, Ostrinia nubilalis (Hubner), is a devastating insect pest in the corn (Zea mays L.) growing regions of North America and Europe. Field evaluations in the USA and Belgium showed that transgenic corn events expressing Cry9C, an insecticidal crystal protein from Bacillus thuringiensis subsp, tolworthi, very effectively control both generations of the European corn barer. Second to fourth instar larvae fed with leaf material of event CBH351 expressing the Cry9C protein air died within 4 d. Cry9C events, expressing high levers of the insecticidal protein, showed minimal stalk tunneling after heavy artificial infestations. Event CBH351 tested in plots containing only Cry9C transgenic plants had 0.14- and 0.09-cm tunneling per stalk compared with more than 30- and 23-cm tunneling par stalls Tor the negative controls, inn the Belgium and Iowa field trial, respectively. In plots containing 30% non-transgenic plants the event CBH351, showed only 1.45-cm tunneling per stalk. Leaf, tassel, and pith tissue contained 39.0, 17.4, and 84.8 mu g Cry9C protein mg(-1) soluble protein, respectively, in analyses conducted at harvest of the Belgium trial. The implications of Cry9C use for resistance management strategies sue discussed.