Submitted to: Journal of Chemical Ecology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/28/2008
Publication Date: 6/27/2008
Citation: Wu, J., Liu, X., Zhang, S., Zhu, Y., Whitworth, R., Chen, M. 2008. Differential Responses of Wheat Inhibitor-Like Genes to Hessian Fly (Mayetiola destructor) Attacks during Compatible and Incompatible Interactions. Journal of Chemical Ecology.34:1005-1012. Interpretive Summary: The Hessian fly (Mayetiola destructor) is one of the most destructive insects of wheat. The insect is currently controlled by host plant resistance. The challenge for the host plant resistance strategy is that resistance conferred by resistance genes is short lived, often lasting for about 6 to 8 years. Therefore, new strategies for durability should be explored. This paper characterized a group of inhibitor-like genes that were strongly suppressed in susceptible plants and were induced in resistant plants. This observation suggests that the inhibitor-like genes may help the wheat to fight Hessian fly damage. Further research may lead to durable resistant cultivars that can effectively control this insect pest.
Technical Abstract: Four groups of inhibitor-like genes encoding proteins with diverse structures were identified from wheat. The majority of these genes were up-regulated by avirulent Hessian fly (Mayetiola destructor) larvae during incompatible interactions, and were down-regulated by virulent larvae during compatible interactions. The upregulation during incompatible interactions and downregulation during compatible interactions resulted in 4 to 30 fold differences between the expression levels in resistant plants and those in susceptible plants. The increased expression of inhibitor-like genes during incompatible interactions suggested that these genes are part of defense mechanisms in wheat against Hessian fly attacks, whereas the downregulation of these genes during compatible interactions suggested that virulent larvae can suppress plant defenses. Both the upregulation of the inhibitor-like genes during incompatible interactions by avirulent larvae and the downregulation during compatible interactions by virulent larvae were through mechanisms that were independent of the wound response pathway.