Submitted to: Plant and Animal Genome Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 11/3/2007
Publication Date: 1/12/2008
Citation: Williams, C.E., Subramanyal, S., Sardesai, N., Minocha, S. 2008. Virulent Hessian fly larvae trigger increased wheat polyamine levels. Plant and Animal Genome Conference Proceedings. Abstract No. P814.
Technical Abstract: The interaction of susceptible wheat (Triticum aestivum, L) with one of its major insect pests, the Hessian fly [Mayetiola destructor (Say)], triggers higher levels of gene transcripts involved in polyamine (PA) biosynthesis. This increase in transcript levels is correlated with increases in the free polyamines, putrescine, spermidine and spermine and also results in increased activity of a key enzyme of the PA biosynthetic pathway, S-adenosyl methionine decarboxylase (SAMDC) in susceptible plants. In contrast, decreased SAMDC activity in resistant plants suggests that the substrate S-adenosylmethionine (SAM) is made available for the synthesis of ethylene, a key molecule in defense-related signal transduction pathways. Expression data suggest preferential synthesis of wheat polyamines from ornithine instead of arginine in response to Hessian fly larval feeding. Analysis of polyamine levels in the Hessian fly larvae show a concurrent increase in free polyamines, suggesting that the larvae induce susceptible wheat to synthesize PA for utilization for their own growth and development.