Phytodecta fornicata Brüggemann resistance mediated by oryzacystatin II proteinase inhibitor transgene

Abstract

Phytodecta fornicata Brüggemann is a serious pest of alfalfa (Medicago sativa L.) that causes significant crop loss in the Balkan peninsula of Europe. We introduced a wound-inducible oryzacystatin II (OCII) gene to alfalfa to evaluate its effect on survival of P. fornicata larvae. Feeding bioassays with second, third and fourth instars were carried out using transgenic plants that were shown to express OCII at 24 and 48 h after wounding. Second and third instars were the most sensitive to the ingestion of OCII, whereas no effects were observed with fourth instars. About 80% of the second and third instars died after 2 days of feeding on the transgenic plants as compared to 0-40% on the controls. This is the first report that demonstrates significant increase in mortality of P. fornicata on transgenic plants that express a cysteine proteinase inhibitor gene, and this knowledge should lead to the development of effective management strategies for this devastating pest of alfalfa. © 2007 Springer Science+Business Media B.V.